A number of studies indicate that milk products may prevent age-related loss of muscle mass and strength. Also known as sarcopenia, it can be prevented and managed by being physically active and getting enough protein and vitamin D in the diet.^1,2 These recommendations are put forward by the International Osteoporosis Foundation¹ and the Society for Sarcopenia, Cachexia and Wasting Disease.²

Seven ways milk products may help prevent and manage sarcopenia

1. Greater skeletal muscle mass^3,4 -- These were the results of two cross-sectional studies in older women (aged 70-85 years), which looked at the association between dairy intake (≥ 2.2 servings/day) skeletal muscle mass and bone structure.
2. Greater total bone mass (including greater appendicular bone mass)³
3. Increased total bone mineral density (including trabecular bone mineral density)³
4. More muscle strength^4,5 -- This was shown in a cross-sectional study that examined hand-grip strength in older women; and from a randomized controlled trial.
5. 5% faster walking and 25% less chance of poor balance⁶ -- Results from a 65-year prospective cohort study revealed that childhood milk consumption can help improve physical performance during late adulthood.
6. Higher-level functional capacity⁷ -- A 7-year prospective study of elderly Japanese linked higher animal protein intake with higher-level functional capacity.
7. Improved energy and nutrient intake⁸ -- Consuming extra servings of milk products was found to help prevent malnutrition and sarcopenia in older adults.

The key nutrients to the benefits listed above appear to be protein and vitamin D.

Protein

• Whey, which is one of the main proteins in milk, has been shown to increase the muscle strengthening effect of resistance training.^2,5
• Because whey is digested quickly, its amino acids are available for faster uptake into the body.⁹
• A randomized controlled trial (the gold standard of studies) showed that protein-rich Ricotta led to increased muscle mass and strength among elderly people.⁵
• Milk protein is also rich in the amino acid, leucine, which is linked to muscle synthesis.^9,10

Vitamin D

• Vitamin D status generally declines with aging.²
• Epidemiological studies indicate that low levels of vitamin D are linked to low muscle strength and increased frailty.
• By contrast, higher levels of vitamin D are associated with increased muscle strength, better physical abilities, fewer falls and less frailty.
• The exact ways vitamin D helps to prevent sarcopenia are still unknown, but may be linked to vitamin D receptors found in muscles.^2,9

More studies are needed to better understand the exact mechanisms in which milk products can prevent and manage sarcopenia, beyond being a source of protein and vitamin D.

Pre-menstrual syndrome (PMS) affects a large proportion of women. Fortunately, certain lifestyle modifications—including adopting a healthy diet— can help control light and mild symptoms. For example, various studies have identified calcium as a key nutrient for counteracting PMS.

Introduction

Pre-menstrual syndrome is defined as a set of physical and emotional symptoms observed during the period prior to menstruation. These symptoms affect 80% to 90% of women of childbearing age.¹ The most commonly experienced symptoms are:

• Irritability,
• Anxiety,
• Depression,
• Breast and lower belly pain,
• Water retention,
• Headaches or migraines.²

The best-known risk factor is heredity. However, other factors appear to increase the intensity of the symptoms:

• Obesity,^3,4
• A diet low in calcium, magnesium and vitamin B₆,^4,5
• A diet high in methylxanthines (coffee, tea, cola, chocolate),^6,7
• Smoking.^3,4,6

While treatments related to pre-menstrual syndrome are generally used to reduce the intensity of the symptoms, certain lifestyle modifications, including a healthy diet, may help women reduce their frequency.

Diet

Various studies have examined the differences between the diet of women who experience pre-menstrual syndrome and the diet of women who do not. An observational study of 171 adolescents found that those who consumed less milk experienced more of certain symptoms such as abdominal cramping, bloating, food cravings and increased appetite.⁸ Similar results were reported in another observational study, which revealed that women who consumed 3 to 4 servings of milk products per day had fewer pre-menstrual symptoms than women who consumed none.⁹

A cross-sectional study of 177 women aged 18 to 24 years examined the association between certain pre-menstrual symptoms and milk product consumption.¹⁰ Researchers found that headaches and social isolation (observed during the pre-menstrual period) were less frequent among women consuming more milk products.

Calcium

Calcium appears to be the main nutrient linked to PMS symptom reduction.¹¹ In fact, a large body of evidence shows a correlation between hypocalcemia and several PMS symptoms such as fatigue, anxiety, depression, mood swings and cramps.¹² Certain authors have therefore looked at adding a calcium supplement as a treatment for PMS.

A literature review identified various non-medication approaches to provide relief to women with pre-menstrual syndrome.¹³ The authors cite, among others, a study indicating that a calcium intake of 1,200 mg/day is associated with a significant decrease in certain pre-menstrual symptoms, such as fatigue, depression, swelling and pain (p = 0.007 following 2 cycles and p < 0.001 following 3 cycles).¹² Moreover, the authors of a systematic review concluded that only calcium could be part of natural treatments used to reduce pre-menstrual symptoms.¹⁴

A randomized, double-blind, parallel study evaluated the impact of taking a calcium supplement (1,000 mg/day) for 3 months among 179 women.¹⁵ The supplement resulted in a decrease in certain pre-menstrual symptoms, such as depression, increased appetite and fatigue.

Similarly, the authors of an observational study noted that calcium levels in the red blood cells of 46 women with pre-menstrual syndrome were lower than those of 50 women who did not experience it.¹⁶

A case-control study of 3,025 participants conducted in the United States found that those with a higher calcium intake had a 30% lower relative risk of pre-menstrual syndrome compared to those with a lower intake.¹⁷ The amount of calcium required to observe this impact was equivalent to 4 servings of milk products per day. In summary, these studies suggest that calcium may have a positive impact on pre-menstrual syndrome.

Furthermore, in a randomized, double-blind, placebo-controlled study, a calcium supplement (1,000 mg/day) was added for 2 menstrual cycles to the diet of women (n = 180) with severe pre-menstrual syndrome.¹⁸ The authors noted a decline in the severity of symptoms among women taking the calcium supplement, but the difference was not significant compared to women taking the placebo. Similar results were observed in a double-blind parallel study (n = 39) with a daily dose of calcium of 1,200 mg for 4 cycles.¹⁹ The observed benefits of taking the calcium supplement were modest and non-significant.

Among the hypotheses raised to explain the impact of calcium on pre-menstrual syndrome, certain authors suggest that there are similarities between pre-menstrual symptoms and those of hypocalcemia (e.g., depression, anxiety and fatigue).²⁰ If these symptoms were, among others, the result of a calcium deficiency, an adequate calcium intake might alleviate some of these symptoms. Another study found that the calcium excretion level varied during the menstrual cycle, which would lead to a lower level of serum calcium during the pre-menstrual period.²¹ Despite these explanations, the mechanism of action of calcium on pre-menstrual syndrome remains unclear.

Vitamin D

In addition to its effects on bone health, vitamin D may provide other benefits. In a case-control study, women with a higher intake of dietary vitamin D (the equivalent of 400 IU/day) had 41% less risk of developing pre-menstrual syndrome.¹⁷

Similarly, the results from a 2010 observational study (n = 186) suggested that an increased intake of dietary vitamin D may be inversely associated with certain pre-menstrual symptoms.⁴ While this association does not reach the significance threshold, the authors noted that the vitamin D intake of women who met the criteria for pre-menstrual syndrome was significantly lower. Overall, the evidence allows us to conclude that vitamin D may play a role in the prevention of pre-menstrual syndrome. However, more studies are needed to further examine this effect. It is also important to note that the mechanisms associated with these effects remain unknown.

Conclusion

Pre-menstrual syndrome affects many women of childbearing age. Certain dietary modifications would make it easier to manage the symptoms. Increased milk product consumption appears to be linked to a reduced risk of pre-menstrual syndrome. More specifically, calcium and vitamin D appear to be the nutrients with the greatest impact on preventing the symptoms associated with pre-menstrual syndrome.

In light of the totality of evidence, including meta-analyses and systematic reviews of prospective studies, there is no association between milk product consumption and mortality risk.

The Evidence

In a 2013 meta-analysis of prospective cohort studies, the association between different sources of saturated fat and mortality was assessed. A total of 26 studies were examined, for a sample size of 1,800,418 participants and follow-up of 5 to 41 years.¹

• Milk, cheese, butter or total dairy consumption were not associated with all-cause mortality;
• Total dairy consumption including milk and cheese was not associated with cardiovascular disease mortality;
• Milk consumption was not associated with cancer mortality.

In another meta-analysis of prospective cohort studies, the association between dairy consumption and stroke risk, including stroke mortality, was evaluated. The analysis consisted of 15 studies, for a total of 764,635 participants and 28,138 stroke events.²

• Total dairy, low-fat dairy, fermented milk and cheese were inversely associated with stroke risk;
• Whole/high-fat dairy, non-fermented dairy, butter and cream were not associated with stroke risk;
• Compared to stroke incidence, there was a stronger inverse association between total dairy consumption and stroke mortality, with risk ratio 0.80 (95% CI 0.76-0.84; p = 0.01);
• A non-linear relationship was found between milk consumption and stroke mortality, with maximum protection at 200 mL/day for a 20% risk reduction (95% CI 0.77-0.84).

A 2014 systematic review evaluated the evidence on dairy and cardiovascular disease risk and mortality. The author stated that the overall evidence indicates that “dairy consumption does not contribute to the risk of all-cause or CVD-specific mortality.”³

In their 2015 prospective cohort study, Praagman et al. examined the association between fermented food products (dairy products, vegetables, meat) and mortality risk, using data from the European Prospective Investigation into Cancer and Nutrition (EPIC)-Netherlands cohort. The study sample consisted of 34,409 Dutch adults aged 20 to 70 years with a follow-up of 15 years.⁴

• There were no associations between yogurt or total fermented dairy foods (yogurt, buttermilk and Quark) and mortality risk;
• Cheese consumption was not associated with all-cause and cancer mortality;
• Higher cheese consumption (30 g/day vs. 16 g/day) was associated with a 20% and 41% risk reduction in cardiovascular and stroke mortality, respectively.

The relationship between dairy consumption and colorectal cancer mortality was assessed in a prospective cohort study conducted in the US. The participants were 1,111 adults with a mean age of 64 years at baseline.⁵

• Milk intake post-diagnosis was inversely associated with all-cause mortality;
• Total calcium intake post-diagnosis was associated with reduced all-cause mortality and colorectal cancer-specific mortality, with risk ratios 0.72 (95% CI 0.53-0.98, p_trend = 0.02) and 0.59 (95% CI 0.33-1.05, p_trend = 0.01), respectively;
• Dairy consumption pre-diagnosis was not associated with any mortality outcomes.

A prospective cohort study examined whether dairy consumption was associated with fatal or non-fatal risk of stroke and coronary heart disease. The study sample included 4,235 Dutch adults aged 55 years and older. Follow-up time was 17 years. The study found the following:⁶

• There was no association between total dairy, low-fat dairy, milk or fermented dairy consumption and stroke mortality;
• High-fat dairy was associated with a significant 12% risk reduction of fatal stroke, with hazard ratio 0.88 per 100 g/day (95% CI 0.79-0.99, p = 0.026);
• An intake of >100 g/day of high-fat dairy was associated with a borderline significant 37% lower risk of fatal stroke (p = 0.07), compared to <50 g/day;
• There was no association between total dairy, high-fat dairy, low-fat dairy, milk or fermented dairy and mortality from coronary heart disease.

Another prospective cohort study was undertaken to investigate the association between dairy consumption and mortality, where dairy foods were not part of the traditional diet. Participants were a representative cohort of 3,810 adults aged 19 to 64 years from the Nutrition and Health Survey in Taiwan. They were followed for 12 to 15 years, and data was linked to death registration.⁷

• A significant inverse dose-response relationship was observed between dairy consumption and all-cause mortality (p_trend = 0.037);
• High dairy consumption (>7 times/week compared to 0 times/week) was associated with decreased cardiovascular disease mortality, with hazard ratio 0.10 (95% CI 0.02-0.52, p_trend = 0.002);
• An inverse but non-significant association was observed between dairy consumption and cancer mortality.

In a Swedish prospective cohort study, it was examined whether milk consumption was related to mortality. The study consisted of 2 Swedish cohorts, for a total of 61,433 women and 45,339 men, and a mean follow-up of 20 and 13 years, respectively.⁸

• An association was observed between higher milk consumption and increased total, cardiovascular and cancer mortality;
• Cheese consumption was significantly associated with a decrease in total and cardiovascular mortality, and was not associated with cancer mortality;
• The consumption of yogurt and soured milk was associated with reduced total, cardiovascular and cancer mortality;
• The possibility of unaccounted confounding in the analysis has been raised by the authors and other experts. Thus, the authors concluded that the results should be interpreted with caution and that independent replication is needed to confirm the findings.

Potential Mechanisms

The mechanisms by which milk and milk products may influence mortality risk remain to be fully elucidated but may be related to several health benefits associated with milk and milk products, including a reduced risk for several important conditions such as cardiovascular disease, type 2 diabetes, hypertension, and certain cancers including colorectal cancer and bladder cancer.

Conclusion

The totality of evidence suggests that milk and milk product consumption is not associated with increased mortality risk.

Additional research is needed to assess whether different types of milk products may have different effects with regards to mortality risk.

Lactose intolerance is a condition that can affect some individuals who have a deficiency in the enzyme lactase resulting in an inability to digest lactose properly. To diagnose lactose intolerance, an objective test such as the hydrogen breath test is needed.

Definition of lactose intolerance

Lactose is a disaccharide found naturally in mammalian milk, including cow’s milk. During normal digestion, it is broken down into glucose and galactose in the small intestine by the enzyme lactase. However, some people are unable to properly digest and absorb lactose.

Lactose intolerance is a clinical syndrome and is defined as the onset of gastrointestinal symptoms following the ingestion of lactose by an individual with lactose malabsorption.^1,2 In a blinded, single-dose challenge of ingested lactose, the same symptoms are not observed when the person ingests an indistinguishable placebo.¹

The symptoms of lactose intolerance result from bacterial fermentation of undigested lactose in the colon.¹ They are directly related to the quantity of lactose ingested and independent of the cause of lactose malabsorption.² Common gastrointestinal symptoms that may occur after lactose ingestion in individuals with lactose intolerance include abdominal pain, diarrhea, flatulence and bloating.

Lactose malabsorption
Lactose malabsorption is the physiologic condition underlying lactose intolerance. Lactose malabsorption occurs due to a decreased ability to digest lactose caused by an insufficient amount of lactase in the small intestine.^1,2

Lactase deficiency
The decline or absence of intestinal lactase is referred to as lactase deficiency. There are several types of lactase deficiency:^2,3

1. Lactase nonpersistence, also known as primary lactase deficiency, is the progressive physiological decline in intestinal lactase due to a decrease in the genetic expression of lactase in early childhood.
2. Secondary lactase deficiency is a temporary condition caused by certain factors that injure the small intestinal mucosa, e.g. acute gastroenteritis, inflammatory diseases such as Crohn’s disease, celiac disease, and some medications. It can occur at any age and is reversible upon correction of the causative factor.
3. Congenital lactase deficiency, also known as congenital alactasia, is an extremely rare autosomal recessive genetic disorder that has been reported in only a few infants. In these cases, newborns do not produce lactase and cannot digest lactose. The condition is evident as it results in severe diarrhea on first exposure to breast milk.

Diagnosis of lactose intolerance

If lactose intolerance is suspected, standardized and objective testing should be done to confirm diagnosis, as it is important to distinguish lactose intolerance from other causes of gastrointestinal symptoms. Self-diagnosis of lactose intolerance is often incorrect and can lead to unnecessary dietary restrictions.²

The hydrogen breath test is the most objective test to diagnose lactose malabsorption.^1,2 The hydrogen breath test requires that patients consume a standard dose of lactose (usually 50 g of lactose, which is equivalent to the amount in 1 L of milk) after fasting. Hydrogen levels in the breath are then measured over a 3-hour period.^2,4 The fermentation of undigested lactose by intestinal flora produces hydrogen, carbon dioxide and methane, which are eliminated by the lungs through the breath. These gases also cause bloating, flatulence, abdominal pain and diarrhea. Lactose malabsorption is diagnosed if hydrogen levels are elevated. In the case of lactose intolerance, gastrointestinal symptoms will also occur. The test is widely used, but its reliability depends on the activity of bacterial flora.⁴ False-negative tests can occur due to several conditions that may affect the intestinal flora, e.g. recent use of antibiotics or antimicrobial agents.

Some other less common tests used to diagnose lactose malabsorption are:^2,4

1. Intestinal biopsy
   Lactase activity from an intestinal sample is measured through direct biochemical assay. However, because of the invasiveness of intestinal biopsies, lactose tolerance tests have been developed.
2. Lactose tolerance test
   This older test has mostly been replaced by the hydrogen breath test due to its high rate of false-negative and false-positive results. The test consists of taking a series of blood glucose measurements over 3 hours, after the ingestion of a lactose load. A diagnosis of lactose malabsorption is consistent with a rise in blood glucose of about <20 mg/dL. False-positive results are often obtained because of a lack of increase in blood glucose, which is attributable to normal insulin response.
3. Genetic testing
   Genetic testing can be conducted for the common polymorphisms that are linked to lactase nonpersistence. However, other polymorphic variants can affect diagnostic accuracy.

Conclusion

Lactose malabsorption is most objectively diagnosed by the hydrogen breath test. However, the majority of people with lactose malabsorption do not have clinical lactose intolerance and do not experience gastrointestinal symptoms following lactose ingestion.

For information, see:

1. Prevalence of Lactose Intolerance
2. Lactose Intolerance: Health Authorities’ Recommendations

The true prevalence of lactose intolerance is unknown. The symptoms of lactose intolerance are highly subjective and may or may not occur among individuals with lactose malabsorption.

Most people are born with the ability to digest lactose. However, in some people, lactose intolerance can occur, whereby lactose digestion and absorption are compromised and gastrointestinal symptoms arise.

Prevalence of lactose intolerance

Many individuals mistakenly ascribe symptoms of a variety of intestinal disorders to lactose intolerance without undergoing testing.¹ Yet, even in the case of lactose malabsorption, an individual may not necessarily be symptomatic. In fact, the majority of individuals who have lactose malabsorption do not have clinical lactose intolerance.²

Symptoms of lactose intolerance are highly subjective and may or may not accompany lactose malabsorption. Many factors determine whether a person who malabsorbs lactose develops gastrointestinal symptoms associated with lactose intolerance. Examples of such factors include the dose of lactose ingested, the residual intestinal lactase activity, the ingestion of other foods or nutrients together with lactose, and individual sensitivity.

Prevalence in Canada
The true prevalence of lactose intolerance is unknown. According to a national Canadian survey, the prevalence of self-reported lactose intolerance is 16%.³ However, many who self-report lactose intolerance show no evidence of lactose malabsorption as determined by objective diagnostic tests. Thus, the cause of their gastrointestinal symptoms is unlikely to be related to lactose.²

For the expert summary on this subject, consult Prevalence of Lactose Intolerance Among Canadian Adults.

Ethnicity and lactose intolerance
The prevalence of lactose intolerance and lactose malabsorption also varies across ethnic groups. It is least prevalent in European Americans, and most common in African Americans, Hispanic Americans and Asian Americans. The ethnic groups in which lactose intolerance prevalence is higher also tend to have a higher prevalence of lactase nonpersistence.^2,4

Age and lactose intolerance
In general, lactose intolerance and malabsorption are not common among young children, especially those younger than 6 years.² Some studies show that lactose malabsorption is more prevalent in children aged 10 to 16 years. However, these trends need to be verified by representative population studies using the case definition of lactose intolerance.¹ Furthermore, there is little evidence that lactose intolerance increases in older individuals.

Conclusion

Tolerance to lactose can change over time. While the prevalence of lactose intolerance is unknown, it is uncommon among newborns and young children.

For information on management strategies for lactose intolerance, consult Lactose Intolerance: Health Authorities’ Recommendations.

Several authorities such as the National Institutes of Health, the American Academy of Pediatrics Committee on Nutrition, and the National Medical Association recommend that milk and milk products remain part of the diets of individuals with lactose intolerance

This overview of how to manage lactose intolerance focuses on the recommendations of national authorities such as the National Institutes of Health,¹ the American Academy of Pediatrics Committee on Nutrition,² and the National Medical Association.³

Health concerns of restricting the consumption of dairy products

Many individuals who perceive themselves to be lactose intolerant avoid dairy products. However, according to health authorities, it is not necessary for those with lactose intolerance to restrict their intake of dairy products or exclude them from their diets.^1-4

Although restricting lactose intake may improve gastrointestinal symptoms, the long-term effects of a diet low in or free of dairy products are of nutritional concern.⁵ Restricting dairy intake deprives individuals of readily accessible sources of calcium, vitamin D and other key nutrients.¹

Evidence indicates that children and adolescents who do not consume the recommended amounts of milk and milk products fail to meet their calcium requirements, which may prevent them from reaching peak bone mass. Insufficient dairy intake may also increase the risk for osteoporosis among older adults and has been linked to a higher risk of fractures.^1,5

Moreover, milk and milk products have beneficial effects on different health outcomes, including a reduction of the risk of hypertension, colorectal cancer and diabetes. In a national multi-ethnic U.S. survey, higher rates of hypertension and diabetes were observed among individuals with self perceived lactose intolerance.⁶

Management strategies for lactose intolerance

Various management approaches have been shown to effectively alleviate the symptoms of lactose intolerance:

1. Ingesting limited amounts of lactose at a time

   It is best to incorporate small amounts of milk or other lactose-containing foods in one's diet and space out intake throughout the day. Most studies show that individuals with lactose intolerance do not experience symptoms after ingesting small amounts of lactose-containing foods. In general, up to 12 grams of lactose (the equivalent of 1 cup of milk) in a single dose can be tolerated without significant symptoms, especially if taken with other foods.¹ Most people with lactose intolerance, including children, can tolerate up to 2 cups of milk a day, divided into smaller quantities.^2,4

2. Consuming milk and dairy products with other foods

   Milk and dairy products are better tolerated if consumed with other foods or incorporated in a dish. The digestion of milk is slowed down when it is taken with a meal, resulting in a slower release of lactose in the small intestine, thereby reducing the lactose load to be digested at any one time.⁷

   Ingestion with other solid foods, particularly those high in soluble fibre, also delays gastric emptying, which provides additional time for intestinal lactase to digest the lactose.^2,4

3. Opting for dairy products such as yogurt, cheese and chocolate milk

   Both yogurt and cheese are produced by the fermentation of milk by lactic acid bacteria. During this process, a certain quantity of lactose is converted to lactic acid. Therefore, yogurt is generally well tolerated, particularly those with active bacterial cultures, which help digest lactose.^4,8 In addition, the semisolid state of yogurt slows gastric emptying and gastrointestinal transit, providing more time for lactose digestion.^2,3

   Some examples of cheeses that contain very little lactose are Mozzarella, Cheddar, Swiss, Brie and Blue (see table below).^1,3

   Chocolate milk also tends to be better tolerated than plain milk, although the reason is unclear.⁷

4. Preferring lactose-free and lactose-reduced milk and dairy products

   In its Updated Consensus Statement, the National Medical Association reports that lactose free dairy products are the most ideal substitute for regular dairy products among individuals with lactose intolerance.³ In addition, evidence indicates that children prefer lactose-free cow’s milk over soy beverages.³

   Furthermore, fortified beverages and other calcium-containing foods are not nutritionally equivalent replacements for cow’s milk. Incorporating such foods in one's diet may alter the overall dietary pattern, resulting in suboptimal intake of other key nutrients such as protein, magnesium, potassium, riboflavin and vitamin B₁₂.³

5. Taking lactase enzyme pills

   Oral lactase enzyme pills are another option to improve lactose digestion for those with lactose intolerance. It is recommended that the pills be taken with the first sip or bite of the dairy product.^1,3

6. Other strategies

   Colonic adaptation is a strategy where lactose intake is gradually increased over time.¹ In some people, routine exposure to lactose can improve the efficiency of colonic bacteria to metabolize lactose, thus improving tolerance.⁴ One approach to build up tolerance is to take half a glass of milk with 1 meal on the first day, then with 2 meals, gradually increasing the frequency and quantity every day.⁷

Calcium and lactose content in common milk products⁹

Conclusion

Lactose intolerance, whether real or perceived, should not be a barrier to achieving a healthy diet.

Milk and milk products are nutritious foods that provide several essential nutrients such as calcium, vitamin D, magnesium, potassium and protein, and are associated with several health benefits including bone health and a reduced risk of hypertension, type 2 diabetes and colorectal cancer.

Among individuals with diagnosed lactose intolerance, various approaches can be employed to maintain milk and milk products as part of a healthy diet.

There is a growing concern about osteoporosis and fractures among Asian populations. Although milk products can help prevent osteoporosis, they are under-consumed by these population groups.

Early studies on osteoporosis and hip fractures among Asians have indicated a low prevalence of these conditions among this ethnic group.¹ It was suggested that the observed low fracture rates are due to the shorter hip axis length and higher trabecular volumetric bone mineral density of Asians.^1,2 However, in its 2013 Asia-Pacific Regional Audit, the International Osteoporosis Foundation reported that osteoporosis and fractures among Asian populations are a main concern.³

Osteoporosis and fracture incidence among Asians is expected to rise

As in many other parts of the world, Asia’s aging population is growing rapidly, and the incidence of fracture in these countries is consequently expected to rise rapidly as well. It is estimated that by 2050, over half of all hip fractures worldwide will occur in Asia, with the majority in China. In fact, over the past 30 years, the incidence of hip fractures in Asian countries has increased 2- to 3-folds.³

Osteoporosis and fractures under-recognized in Asian countries

The 2013 Asia-Pacific Regional Audit also emphasizes that the burden of osteoporosis and fractures is severely under-estimated in Asian countries. Additionally, osteoporosis remains under-diagnosed and under-treated, which may explain the belief that this condition is less frequent in these populations.

Diagnosing osteoporosis in Asians has proven to be difficult because of the lack of ethnic-specific criteria and the limited access to diagnostic tools. Other issues contributing to this problem include poor access to treatment and low awareness among the public and health professionals.³

Moreover, there is limited epidemiological research and data on osteoporosis in Asian groups. Asians, particularly the Chinese, tend to have relatively high rates of vertebral fractures but lower rates of non-vertebral fractures. This may be because the Chinese have different skeletal microstructure, mechanical competence and bone remodeling.⁴

Calcium and vitamin D intake is inadequate among Asians

It is well recognized that adequate calcium and vitamin D intakes are necessary for bone health. However, milk products, which are a main source of these nutrients, are under-consumed by Asians.³

Studies have indicated that calcium intakes throughout Asia are well below the daily recommended amount of 1,000 mg to 1,200 mg, and the average daily calcium intake in some Asian countries has been found to be below 500 mg. Furthermore, little improvement in calcium intake has been observed over the past years.³

Low vitamin D status is prevalent among all age groups in Asia. The average vitamin D level in Asian countries is reported to be 25 to 49 nmol/L, which is well below the recommended 75 nmol/L. Evidence indicates that these low levels of vitamin D may be due to inadequate dietary vitamin D intake, a lack of food fortification with vitamin D, as well as urbanization and decreased sun exposure.³

Conclusion

Osteoporosis and fractures are a main concern among all world populations, including Asians. Milk product intake, as well as calcium and vitamin D intake, tends to be low among these population groups.

While additional research is needed to understand the epidemiology and mechanisms of osteoporosis and fractures among Asians, greater efforts are also required to improve their nutritional intake, in terms of milk products, calcium and vitamin D, in order to counter the rise in fracture incidence.

According to Canada’s Food Guide, a balanced diet for adults should include 2 to 3 servings of Milk and Alternatives per day. One serving equals 1 cup (250 mL) of milk, ¾ cup (175 g) of yogurt or 1½ ounces (50 g) of cheese.

For more information, consult Bone Health and Osteoporosis.

There is a growing concern about osteoporosis and fractures among Asian populations. Although milk products can help prevent osteoporosis, they are under-consumed by these population groups.

Early studies on osteoporosis and hip fractures among Asians have indicated a low prevalence of these conditions among this ethnic group.¹ It was suggested that the observed low fracture rates are due to the shorter hip axis length and higher trabecular volumetric bone mineral density of Asians.^1,2 However, in its 2013 Asia-Pacific Regional Audit, the International Osteoporosis Foundation reported that osteoporosis and fractures among Asian populations are a main concern.³

Osteoporosis and fracture incidence among Asians is expected to rise

As in many other parts of the world, Asia’s aging population is growing rapidly, and the incidence of fracture in these countries is consequently expected to rise rapidly as well. It is estimated that by 2050, over half of all hip fractures worldwide will occur in Asia, with the majority in China. In fact, over the past 30 years, the incidence of hip fractures in Asian countries has increased 2- to 3-folds.³

Osteoporosis and fractures under-recognized in Asian countries

The 2013 Asia-Pacific Regional Audit also emphasizes that the burden of osteoporosis and fractures is severely under-estimated in Asian countries. Additionally, osteoporosis remains under-diagnosed and under-treated, which may explain the belief that this condition is less frequent in these populations.

Diagnosing osteoporosis in Asians has proven to be difficult because of the lack of ethnic-specific criteria and the limited access to diagnostic tools. Other issues contributing to this problem include poor access to treatment and low awareness among the public and health professionals.³

Moreover, there is limited epidemiological research and data on osteoporosis in Asian groups. Asians, particularly the Chinese, tend to have relatively high rates of vertebral fractures but lower rates of non-vertebral fractures. This may be because the Chinese have different skeletal microstructure, mechanical competence and bone remodeling.⁴

Calcium and vitamin D intake is inadequate among Asians

It is well recognized that adequate calcium and vitamin D intakes are necessary for bone health. However, milk products, which are a main source of these nutrients, are under-consumed by Asians.³

Studies have indicated that calcium intakes throughout Asia are well below the daily recommended amount of 1,000 mg to 1,200 mg, and the average daily calcium intake in some Asian countries has been found to be below 500 mg. Furthermore, little improvement in calcium intake has been observed over the past years.³

Low vitamin D status is prevalent among all age groups in Asia. The average vitamin D level in Asian countries is reported to be 25 to 49 nmol/L, which is well below the recommended 75 nmol/L. Evidence indicates that these low levels of vitamin D may be due to inadequate dietary vitamin D intake, a lack of food fortification with vitamin D, as well as urbanization and decreased sun exposure.³

Conclusion

Osteoporosis and fractures are a main concern among all world populations, including Asians. Milk product intake, as well as calcium and vitamin D intake, tends to be low among these population groups.

While additional research is needed to understand the epidemiology and mechanisms of osteoporosis and fractures among Asians, greater efforts are also required to improve their nutritional intake, in terms of milk products, calcium and vitamin D, in order to counter the rise in fracture incidence.

According to Canada’s Food Guide, a balanced diet for adults should include 2 to 3 servings of Milk and Alternatives per day. One serving equals 1 cup (250 mL) of milk, ¾ cup (175 g) of yogurt or 1½ ounces (50 g) of cheese.

For more information, consult Bone Health and Osteoporosis.

It is important that the diet of young athletes meets nutritional recommendations. This is what our research team examined at the 2011 Quebec and Canada Winter Games.

The objectives of this study were to determine the factors that influence food choices among young Canadian athletes before, during, and after major competitions, to analyze whether their food choices meet nutritional recommendations, and to examine the coach’s role with regard to sports nutrition.

First, the diets of participants were examined during the 2011 Quebec and Canada Winter Games. Data collection was performed by taking photographs of the athletes’ trays in the area where they normally ate. The analysis of the athletes’ food choices was based on nutritional criteria that defined optimal food choices during meals as well as according to the time between meals and exercise (before and after exercise). To evaluate whether the food choices corresponded to the nutritional recommendations, three components were analyzed per meal: macronutrient distribution and variety, energy, and liquid intake. Data were also collected on the nutritional recommendations provided by these sporting events. During the Quebec Games, athlete nutrition was guided by a nutrition policy, whereas during the Canada Games, no such policy was implemented.

Second, a survey was conducted among the athletes and coaches to validate the collected data and determine which factors would be favourable to an optimal transfer of nutrition knowledge between young athletes and coaches.

Our observations and analyses showed that there is a need for nutrition training among young athletes, mainly regarding their food choices before and during competition, regardless of the level and type of sport. Also, the development of nutrition policies to provide athletes meals that meet nutritional recommendations established by scientific authorities (ACSM, ADA, DC and AIS*) should be considered. An approach is also needed to tackle problems related to athlete nutrition among this age group. Lastly, there should be a focus on providing nutrition education to coaches, since they can provide the most accessible information to athletes.

*ACSM: American College of Sports Medicine; ADA: American Dietetic Association; DC: Dietitians of Canada; AIS: Australian Institute of Sport.

It is well known that vitamin D influences the development and maintenance of bone mass and reduces the risk of osteoporosis. Furthermore, it is also thought to improve lower limb neuromuscular function.

Introduction

Vitamin D from food, supplements and sun exposure is first transformed in the liver into 25‑hydroxyvitamin D [25(OH)D] and is then activated in the kidneys as 1,25-dihydroxyvitamin D or calcitriol.¹ This hormonally active form is responsible for the homeostasis of calcium and phosphorus, whereas serum 25(OH)D concentrations reflect vitamin D status.² Serum 25(OH)D concentrations and intakes of vitamin D (from both food and supplements) may be significantly and positively associated with bone mineral density (BMD).^1,3

Aging leads to a loss of bone mass and decreased vitamin D synthesis, which may contribute to the development of osteoporosis. Inadequate intake of calcium and vitamin D may aggravate the situation and increase the risk in particular of vertebral, hip and forearm fractures.¹ Osteoporosis is more common in women than men⁴ due to decreased concentrations of estrogen at menopause, which promote a reduction in BMD.

The beneficial effects of vitamin D on the absorption and use of calcium and phosphorus, its contribution to the development of solid bones, and its ability to reduce the risk of osteoporosis are recognized by different health authorities, including Health Canada, the U.S. Food and Drug Administration (FDA), the Institute of Medicine (IOM) and the European Food Safety Authority (EFSA).¹ According to these agencies, data support the conclusion that there is an independent cause-and-effect relationship between calcium and vitamin D intakes and the growth, development and maintenance of bones and teeth, and a reduced risk of osteoporotic fracture.

The Evidence

After conducting a comprehensive review of the evidence to date, the IOM found data suggesting that there is a dose-dependent association between 25(OH)D concentrations and bone mineral content in children over the age of 6 months, adolescents, and adults (both younger and older) of different ethnic origins.¹ A vitamin D serum concentration of 50 nmol/L was deemed to be sufficient to ensure bone health outcomes.¹

Data have also demonstrated that treatment combining a vitamin D supplement and a calcium supplement may also reduce bone loss and may lead to a greater increase in BMD compared to treatment without vitamin D.⁵ Vitamin D may also improve lower limb neuromuscular function and decrease the frequency of falls.⁵

The results of a 2010 meta-analysis of 8 studies indicate that combined vitamin D and calcium supplementation can decrease the incidence of nonvertebral fractures by 23% and hip fractures by 30%.⁶

• This supplementation may also reduce fractures other than hip fractures to a greater degree compared to calcium supplementation alone;
• Fractures of the hip and vertebrae seem to be more frequent among older people with deficient intakes of vitamin D and calcium, whereas other fractures are more common among people who are older but who are active and who have higher intakes of these two nutrients.

A 2009 meta-analysis of 20 randomized controlled trials on fractures in people over the age of 65 showed that vitamin D supplementation of more than 482 IU per day reduced nonvertebral fractures by 20% and hip fractures by 18%.⁷

• The reduction in nonvertebral fractures was greater when higher doses of vitamin D were used;
• In terms of supplementation with doses below 400 IU, no decrease in hip fractures was observed;
• The addition of calcium to the vitamin D supplementation did not influence the reduction of nonvertebral fractures;
• Cholecalciferol (D₃) seems to be more effective than ergocalciferol (D₂) at decreasing fractures, as, at an equivalent dose, it seems to increase 25(OH)D levels to a greater degree because of greater vitamin D receptor affinity.

Another meta-analysis of randomized controlled trials indicated that vitamin D supplementation in people at risk of hip fractures (postmenopausal women or men aged 50 years and over) reduced the risk of hip fractures by 18% only when the supplement was combined with calcium.⁸

Similarly, a meta-analysis of 45 studies revealed that combined supplementation with 400 to 800 IU of vitamin D and 1,000 mg of calcium per day reduced the incidence of hip fractures by 16%.⁹ However, this effect may be greater for individuals whose daily intakes of vitamin D are below 400 IU. Furthermore, vitamin D supplements alone and those that combined both vitamin D and calcium were less effective at preventing fractures than calcium supplements alone.⁹

Potential Mechanisms

Vitamin D regulates blood calcium levels by improving the intestinal absorption of calcium and minimizing its elimination in the urine. It also plays a role in the deposit of calcium in bone and the removal of calcium from bone to meet the body's needs.¹ A vitamin D deficiency results in a low absorption of calcium and elevated concentrations of parathyroid hormone (PTH), a hormone that acts to increase blood calcium levels by releasing calcium from the bones.¹⁰

Over the long term, vitamin D deficiency leads to a loss of bone mass, which weakens the bones and causes osteoporosis. Adequate vitamin D intake decreases bone loss by reducing the secretion of PTH and prevents excessive bone remodelling (bone turnover). Several data show that high bone remodelling rates increase bone fragility.¹ Furthermore, this rate doubles across menopause and triples by the age of 65 years.

Conclusions

Vitamin D plays a role in helping people reach and maintain adequate BMD. Some populations, such as children who present with a vitamin D deficiency and seniors living in long-term care facilities, would benefit more from vitamin D supplementation. The dose of vitamin D required to reduce the incidence of fractures is controversial. In studies that showed evidence of decreased fractures in seniors, a minimum dose of 400 IU of vitamin D was required.

To ensure the maintenance of bone health, the IOM recommends a serum 25(OH)D concentration of 50 nmol/L. However, some experts suggest that concentrations should be above 75 nmol/L.^1,11 These concentrations would limit bone resorption and demineralization by preventing an increase in PTH levels. As a preventive measure, Health Canada recommends that all adults over the age of 50 years take a daily vitamin D supplement of 400 IU.¹ However, Osteoporosis Canada suggests that adults under the age of 50 years take a supplement of 400 to 1,000 IU per day and that people over the age of 50 years or younger adults at higher risk of osteoporosis take a supplement of 800 to 2,000 IU per day.¹⁴

Front-of-package labelling systems have been proposed as an approach to guide healthier food choices at the point of purchase. However, it is inconclusive whether front-of-package labels influence consumer purchasing behaviour.

The evidence concerning the effect of front-of-package labelling on food choices and purchasing behaviour is limited. While front-of-package labels may play a role in the perceived healthiness of certain food items, few studies have evaluated the impact of front-of-package labelling on consumer behaviour in a real-life setting. Some of the studies suggest that the use of such labelling systems does not influence consumer behaviour.

For more information, see Consumer perception and understanding of front-of-package nutrition labelling.

The Evidence

A 2013 systematic review by Hawley et al. was inconclusive as to whether the use of front-of-package labels influenced consumer behaviour. This was due to the lack of real-world studies that evaluate sales data and consumer behaviour in response to front-of-package labelling.¹

Another systematic review published in 2013 assessed the effect of front-of-package labelling systems on consumers. Mixed results were obtained from relatively few studies regarding the influence of front-of-package labelling on consumers’ likelihood to select healthier foods and adopt healthier diets.²

The systematic reviews included the following findings:

• ^· A randomized experimental study of 420 adults in Germany found that the use of front-of-package labels on various food items, including dairy products such as yogurt, cheese and chocolate milk, did not have an effect on daily food consumption, even after adjusting for different subject characteristics. The study concluded that the healthiness of food, as perceived through food labels, is unlikely to influence food choices and consumption.³
• In a study by Sacks et al., the impact of front-of-package "traffic light" labelling on consumer food purchases was examined. The results indicated that "traffic light" labels had no discernible effect on the healthiness of consumer purchases.⁴

The American Heart Association published a 2012 Scientific Statement on population approaches to improve diet. Based on their systematic review, the authors concluded that “In sum, there is limited evidence that (…) front-of-pack product labels or icons, or point-of purchase listing of calories or specific nutrients, have consistent meaningful effects on dietary behaviours of consumers. (…) There is limited evidence that these labels or icons produce actual dietary change or alter other diet-related risk factors, especially over the long-term”.⁵

In contrast, a between-group experimental study evaluated the efficacy of four types of front-of-package sodium labels at influencing consumers’ selection of crackers. Compared to the control group, those assigned to front-of-package labels with ‘high/low’ sodium descriptors were more likely to choose lower-sodium crackers.⁶

Conclusion

To date, it is inconclusive whether the use of front-of-package labelling has an effect on food choices and purchasing behaviour. Most studies do not support that front-of-package labels have a substantial impact on consumer behaviour.

Findings from some studies suggest that certain types of labels may have an effect on the choice of specific products. However, generalizability is limited with regards to all front-of-package labelling systems as well as to the wide variety of food products available on the market.

Moreover, the numerous types of front-of-package labelling systems have not all been evaluated. More studies conducted in real-life settings are needed to fully clarify whether the use of front-of-package labelling influences food choices and dietary intake.

Our muscles are constantly in balance between anabolism (growth) and catabolism (breakdown). For anabolism to take place, we need to fuel muscles with protein. Exercise also gives muscles a further push to grow. Optimal distribution of protein at each meal appears to be a key factor in building and maintaining muscle mass throughout life.

Our team has been investigating how North American eating habits pertaining to protein affect the maintenance of muscle mass during the aging process. In one study, we gave subjects a 30-gram serving of protein (115 g lean beef) and, over the next four hours, measured how their muscles responded. There was a robust improvement in protein synthesis in both young and elderly adults, suggesting that aging doesn’t inevitably impair our ability to turn dietary protein into muscle.

While a moderate amount of protein (about 30 grams/meal) can increase muscle protein synthesis, there may be a ceiling effect. For most adults, consuming much more protein than 30 grams/meal provides additional energy, but is not likely to provide a further increase in muscle protein synthesis. When young adults halve their protein intake (from 30 to 15 grams/meal), their muscle protein synthesis is also reduced by approximately 50%.

Unfortunately, North American distribution of protein is skewed (i.e., most of it consumed at supper and less at breakfast and lunch) and fails to maximize potential muscle growth and repair. We get the greatest benefit by distributing protein evenly across meals: about 30 grams each at breakfast, lunch and supper (the 30-30-30 g Protein Rule).

Exercise is also important for all ages. We observed as much as an additional 50% increase in protein synthesis when a modest bout of exercise was performed within an hour or two of eating.

Our muscles are constantly in balance between anabolism (growth) and catabolism (breakdown). For anabolism to take place, we need to fuel muscles with protein. Exercise also gives muscles a further push to grow. Optimal distribution of protein at each meal appears to be a key factor in building and maintaining muscle mass throughout life.

Our team has been investigating how North American eating habits pertaining to protein affect the maintenance of muscle mass during the aging process. In one study, we gave subjects a 30-gram serving of protein (115 g lean beef) and, over the next four hours, measured how their muscles responded. There was a robust improvement in protein synthesis in both young and elderly adults, suggesting that aging doesn’t inevitably impair our ability to turn dietary protein into muscle.

While a moderate amount of protein (about 30 grams/meal) can increase muscle protein synthesis, there may be a ceiling effect. For most adults, consuming much more protein than 30 grams/meal provides additional energy, but is not likely to provide a further increase in muscle protein synthesis. When young adults halve their protein intake (from 30 to 15 grams/meal), their muscle protein synthesis is also reduced by approximately 50%.

Unfortunately, North American distribution of protein is skewed (i.e., most of it consumed at supper and less at breakfast and lunch) and fails to maximize potential muscle growth and repair. We get the greatest benefit by distributing protein evenly across meals: about 30 grams each at breakfast, lunch and supper (the 30-30-30 g Protein Rule).

Exercise is also important for all ages. We observed as much as an additional 50% increase in protein synthesis when a modest bout of exercise was performed within an hour or two of eating.

Evidence from randomized controlled trials suggests that fermented milk products, such as yogurt, may enhance the immune system.

The development and maintenance of the immune system depend largely on healthy gut microbiota. As fermented and probiotic milk products are a source of beneficial live microorganisms that can improve gut microbiota, a number of studies have investigated the role of these products in immune regulation. To date, the available evidence suggests that fermented milk products may enhance immune functions.

The Evidence

A randomized controlled trial by Meyer et al. evaluated whether yogurt consumption had stimulating effects on the immune system. Thirty-three healthy women aged 22 to 29 years were randomized to either a conventional or a probiotic yogurt. The subjects consumed 100 g per day of the respective products for 2 weeks, and the amount was increased to 200 g for the subsequent 2 weeks. It was found that both products enhanced cellular immune functions, but there was no significant difference between them.¹

In another randomized controlled trial, the effect of the dietary deprivation of fermented foods on the immune system was assessed. The study consisted of 20 healthy adult volunteers aged 23 to 43 years who regularly consumed yogurt and/or cheese (at least 5 servings per week) and other fermented products (at least 3 servings per week). They were instructed not to consume any fermented products for 2 weeks. Following this restriction, the participants were randomized to the daily consumption of 200 mL of either regular or probiotic yogurt for 2 weeks.²

• The deprivation of fermented foods was associated with a fall in innate immune response;
• Both the regular and probiotic yogurt counteracted the adverse immunological effect;
• The probiotic yogurt was more effective than the regular yogurt at counteracting the fall in immune response.

Marcos et al. conducted a prospective randomized controlled trial to investigate the effect of milk fermented with yogurt cultures plus Lactobacillus casei on the immune system of individuals under academic examination stress. The participants were 155 healthy university students aged 18 to 23 years. For 6 weeks, they were assigned to either 1 daily glass of semi-skimmed milk or 2 daily servings of 100 mL of the fermented milk product. The results indicated that the fermented milk product may modulate immune response among individuals under academic examination stress.³

In addition to human studies, several animal models have been used to examine the immunomodulatory effect of milk products. In a 2012 study, it was observed that a cheese-containing diet modulated immune responses in mice.⁴ Another study suggested that a fermented milk product with 2 probiotics and a prebiotic may have a beneficial effect on the humoral and cell-mediated immunity of host animals.⁵

Potential Mechanisms

Fermented milk products contain large quantities of beneficial bacteria such as lactic acid bacteria, which may enhance both innate and adaptive immunity. The immunomodulatory activity of lactic acid bacteria includes the activation of the systemic and secretory immune response via the coordination of interactions between the microbiota, epithelial cells and immune cells.⁶

Milk and milk products contain bioactive peptides that have been shown to increase the activity of immune system cells. Evidence suggests that these peptides assist in the proliferation of lymphocytes, the functioning of natural killer cells, the synthesis of antibodies and the production of cytokines.⁷ It has been demonstrated that both conventional and probiotic yogurt may stimulate cytokine production and promote higher alertness of the immune system.⁸

Lactoferrin, an iron-binding glycoprotein found in milk and milk products, is an immune modulator and has antimicrobial and antioxidant properties. It influences innate and adaptive immunity by modulating the migration, maturation and functions of immune cells.⁹

Conclusion

Evidence on the immunological properties of milk products comes principally from studies on fermented milk products. These studies indicate that both conventional and probiotic fermented milk products such as yogurt may strengthen the immune system.

Further research from randomized controlled trials is needed to determine whether conventional and probiotic fermented milk products have different effects. Additional studies are also needed to investigate the potential benefits of different types of milk products.

For more information, see the article Probiotic Milk Products and Digestive Health

While some studies show that front-of-package labelling helps consumers identify healthier foods, others suggest that consumers may misinterpret these labels. The understanding of front-of-package labelling appears to depend on a combination of factors related to the label format and consumer characteristics.

What is front-of-package labelling?

Front-of-package labelling refers to symbols and rating systems, including shelf-tag labels, which are designed to summarize the key nutritional characteristics of food products.¹ Front-of-package labels have been proposed as an approach to help consumers make healthier food choices at the point of purchase. However, there are concerns about the possible misinterpretation of front-of-package labels.

What is the optimal front-of-package format?

Currently, there is no consensus on the most effective front-of-package format. There is a wide variety of front-of-package labelling systems that are inconsistent, which may add to consumers’ confusion.² In its 2011 report, the Institute of Medicine recommended a single, simple and standardized front-of-package system.¹

While some studies have found that a single and simple format may be preferable, others have found that consumers value labels that are more complex and detailed.^3-5 A 2013 systematic review concluded that nutrient-specific labels (which provide individual rating for certain nutrients), in contrast to summary systems (which are based on an overall nutritional score), helped consumers more easily identify healthier foods. The text and colour that indicate nutrient levels were also more helpful than actual numeric information in the interpretation of the labels.⁶

It has been suggested that the preference and understanding of front-of-package labels may vary according to consumer characteristics, such as ethnicity and socioeconomic status.^7,8 The understanding of label information also appears to depend on nutrition knowledge.^7,9

What are some other concerns related to front-of-package labelling?

One issue with front-of-package systems is that instead of indicating the overall nutritional quality of food products and their contribution to a healthy diet, they indicate healthiness based on the content of specific nutrients. This may mislead consumers and give them a false perception of the nutritional value of a food product. For instance, a Canadian survey found that front-of-package labels, such as a “traffic light” system, may decrease the perceived healthiness of wholesome foods that are included in Eating Well with Canada’s Food Guide, for example salmon, eggs, almonds, certain types of cereals made with wheat bran fibre, and cheese. Conversely, the study found that the front-of-package labels led to increased perceived healthiness of less nutritious foods that are not part of the four food groups, such as sugar-free gelatin desserts, fruit punch and diet soda.¹⁰

Study limitations

Most front-of-package studies are non-experimental surveys and are not conducted in a real-life shopping setting.⁶ The results may also differ depending on the front-of-package labels or food products that are examined. Furthermore, the results of the studies may not be generalizable given the participant profiles, sample sizes and locations.

Also, there is limited data on the relationship between other information on the package (such as nutrition claims and the Nutrition Facts Table) and the front-of-package label. Moreover, even if consumers accurately understand front-of-package labels, it is not evident that this understanding will change purchasing behaviour or that consumers will actually choose the healthier options.

For more information, see Impact of front-of-package labelling on food choices and purchasing behaviour.

Conclusion

The ability of consumers to correctly understand front-of-package labels appears to depend not only on the features of the labels but also on consumer characteristics.

Because front-of-package labelling systems in general rate the healthiness of foods based on certain nutrients rather than the food as a whole, these labels may not give an accurate idea of the food’s overall nutritional value or its contribution to a healthy diet.

Whether there is an optimal format for front-of-package labels that can be easily understood remains to be determined.

The nutrients in milk products play an essential role in the development of solid bones in children and adolescents, thereby decreasing fracture risk during growth.

Introduction

Scientific evidence suggests that an adequate intake of milk products during growth may optimize bone mass and may help create denser and stronger bones, thereby decreasing fracture risk. Therefore, the fact that the vast majority of young Canadians do not meet the recommendations for this food group represents a major public health issue.

The Evidence

The results from a systematic review and meta-analysis of 12 randomized and non-randomized controlled trials suggest that the addition of 245 mL of milk per day to the regular diets of children aged 3 to 13 years may increase their height by 0.4 cm per year of growth.¹ Milk may have more effect on growth than other milk products. Furthermore, having a lower height-for-age and approaching pubertal growth spurt increase the effect of milk products on height.

A second meta-analysis of 21 randomized controlled trials of 3,821 children (83% girls) aged 4 to 17 years was conducted to determine the impact of milk products and dietary calcium on bone mass.²

• In studies conducted on children with low calcium intakes at baseline, the authors observed significant benefits from milk product consumption or calcium supplement use on bone mineral content;
• An increased intake of dietary calcium or milk products, with and without vitamin D, significantly increased total lumbar spine bone mineral content in children with low baseline calcium intakes.

The benefits of milk products and dietary calcium on bone growth have also been highlighted in longitudinal studies such as the Framingham Children’s Study.³ Indeed, the authors of this study collected dietary data over a period of 12 years for 106 children aged 3 to 5 years at baseline. The results showed that:

• The children who consumed an average of 2 servings or more of milk products per day throughout childhood had significantly better bone health (bone mineral content, bone area, bone mineral density) than children who consumed fewer than 2 servings per day;
• Milk product consumption between the ages of 13 and 17 years may be a more important indicator of bone growth than it is at a younger age;
• Children with high milk product intakes, combined with a high intake of protein from meat or other non-dairy sources, presented with the highest average values of bone mineral content and bone area.

In another longitudinal study consisting of a long-term randomized controlled trial with an observational component, the impact of calcium supplements and milk product intake was evaluated in pre-pubertal children over a 7-year period.⁴ The results showed that:

• By the average age of 15 years, the children of the dairy group were significantly taller and had higher dietary calcium and protein intakes compared to the children of the calcium supplemented and placebo groups;
• The children of the dairy group had a higher bone mineral density of the spine at the age of approximately 15 years and this was maintained up to the age of approximately 18 years;
• Bone mineral density of the hip in the dairy group was similar to that of the calcium supplemented group;
• In general, this study indicated that calcium and milk products influence the acquisition of bone mass, which in turn increases maximum peak bone mass.

The results of observational studies are consistent with those from randomized controlled trials and longitudinal studies. A cross-sectional study published in 2009 consisting of 192 healthy adolescent girls and young women aged 12 to 22 years looked at the effects of milk product consumption and calcium intake from other food sources on bone health.⁵ The authors observed that:

• Milk intake was not significantly associated with any of the studied parameters in premenarcheal girls;
• Bone mineral content and bone mineral density were significantly associated with milk intake in postmenarcheal girls;
• Adolescent girls and young women who consumed less than 55 mL of milk per day had an 8% lower bone mineral content and a 7% lower bone mineral density compared to girls who consumed over 260 mL per day;
• The percentage of girls with osteopenia was higher among low milk consumers (27%), and even more so among girls over 16 years (43%), than among high milk consumers (11%);
• Bone mineral content and bone mineral density in postmenarcheal girls were significantly associated with calcium, phosphate, magnesium, protein and energy intake from milk, but not with the intake of these same nutrients provided by other dietary sources.

Similar to previous studies that showed the beneficial effects of milk products on bone density, a systematic review and meta-analysis showed that the acquisition of maximum peak bone mass is a major determining factor for fracture risk during childhood and adolescence.⁶

The increase in bone mass associated with an adequate and regular intake of milk products and dietary calcium in children and adolescents may therefore have an important clinical impact in terms of decreased fracture risk in adolescence. Indeed, fracture risk may be 3 times higher among children who do not consume milk compared to those of similar ages who do consume milk.⁷

Potential Mechanisms

An adequate intake of milk products is essential for optimal bone health. This seems to be even more true during childhood and adolescence, which are periods when bone tissue development is at its highest. The most important dietary factor related to bone health is still calcium, as this is the main mineral contained in bone tissue. In addition to being an excellent source of calcium, milk products contain several other nutrients that have a positive impact on bone health and growth, such as vitamin D, protein, phosphorus, magnesium, zinc and potassium.⁸ Furthermore, it has been demonstrated that a number of these nutrients in milk products interact, thereby greatly increasing their beneficial effect on bone health.^8,9

The potential mechanisms through which the nutrients in milk products may have a positive impact on bone health and may prevent fractures have not been fully elucidated. According to available data, it is nevertheless possible to divide these nutrients into two categories:

1. Nutrients that are involved in the composition of bone tissue and that promote its growth, such as calcium, phosphorus, protein, magnesium and zinc;
2. Nutrients that promote the absorption of calcium and its beneficial functions on bone health and growth, such as vitamin D and potassium.

Conclusions

Childhood and adolescence are critical periods for the development of solid bones. The scientific evidence to date suggests that an adequate intake of milk products and dietary calcium—an intake that meets the increased demand associated with the rapid growth of bone tissue during childhood and adolescence—optimizes bone development, which results in denser and stronger bones. The main impact may be a decrease in fracture risk during childhood and adolescence and possibly later in life as well.

Probiotic products consist of specific strains of live bacteria that have potentially favourable health effects. A number of studies provide evidence that milk products with probiotics may be beneficial for digestive health and may improve various digestive problems.

Probiotics are defined as “live microorganisms which, when administered in adequate amounts, confer a health benefit on the host.”¹ This term refers to specific strains of bacteria, and typical probiotics include lactic acid bacteria such as Lactobacillus and Bifidobacterium. These strains are widely used in the fermentation of dairy products, such as yogurt, cheese and kefir. Fermented dairy products with active bacterial cultures are therefore one of the most common sources of probiotics. These types of probiotic-containing milk products may be beneficial for a number of gastrointestinal and digestive conditions.^2,3

The Evidence

Helicobacter pylori Infection
A 2009 systematic review and meta-analysis of randomized controlled trials evaluated the effect of fermented milk products enriched with probiotics on Helicobacter pylori infection. A total of 10 eligible studies, which included 963 adults and children, were assessed. It was found that fermented milk-based probiotic preparations reduce Helicobacter pylori infection rates by approximately 5% to 15%.⁴

A prospective study published in 2012 examined the effect of probiotic-containing yogurt on systemic immunological response among 38 children with Helicobacter pylori infection. The study concluded that intestinal microbiota balance can be maintained and humoral and cellular immunity can be stimulated in children who regularly consume yogurt.⁵

Irritable Bowel Syndrome
A review of 42 trials systematically examined the role of lactic acid bacteria, such as lactobacilli, bifidobacteria, enterococci, streptococci and bacilli, on irritable bowel syndrome. A majority of the clinical trials reviewed showed that lactic acid bacteria alleviate abdominal pain and discomfort. Both single- and multi-centre studies have shown that lactic acid bacteria may improve abdominal bloating and distension. Out of 24 trials, improvements in bowel habit satisfaction were found in 13 studies, and 16 trials reported improvements in symptom severity.⁶

A 2013 randomized controlled trial investigated the efficacy of a probiotic yogurt in irritable bowel syndrome. A total of 83 Korean adults were randomized to the treatment or control group. The treatment group was assigned a probiotic plain liquid yogurt containing Lactobacillus rhamnosus GG twice daily over 6 weeks, while the placebo group consumed plain liquid yogurt without probiotics. There was an overall improvement in the symptoms of patients who consumed the probiotic yogurt. As well, the consumption of probiotic yogurt led to beneficial changes for certain types of gut microbiota. The control group also had some improvements, although fewer than the treatment group.⁷

Another multi-centre, double-blind, randomized controlled trial, also published in 2013, was conducted in England to evaluate the effect of a probiotic versus non-probiotic yogurt in irritable bowel syndrome with constipation. The study consisted of 179 adults who were randomized to consume one of these two products twice daily over 12 weeks. Significant improvements were observed for both groups but there was no difference between groups.⁸

Inflammatory Bowel Disease
Probiotics could have beneficial effects on inflammatory bowel disease, but the evidence is limited. According to a systematic review and meta-analysis, the effects could differ depending on disease subtype and probiotic strain.⁹ In addition, findings from a cohort study of middle-aged women living in France indicate that milk products are a protein source that does not increase the risk of inflammatory bowel disease.¹⁰

Antibiotic-Associated Diarrhea
Evidence demonstrates that probiotics are associated with reduced antibiotic-associated diarrhea. In a meta-analysis of 82 randomized controlled trials, a statistically significant association was found between the administration of probiotics and the reduction of antibiotic-associated diarrhea. Various studies included in the meta-analysis consisted of interventions with probiotic milk products, which showed that probiotic milk products may be efficacious in preventing antibiotic-associated diarrhea.¹¹

Constipation
A 2013 meta-analysis of randomized controlled trials indicated that short-term probiotic supplementation reduces intestinal transit time. Greater effects were observed among adults who were older or constipated. Certain probiotic strains, such as strains of Bifidobacterium lactis, appear to be more efficacious.¹²

Lactose Intolerance
In an evidence-based report on lactose intolerance and health published in 2010, a systematic review of the literature indicated that there was insufficient evidence to determine the effectiveness of yogurt and probiotics in alleviating the symptoms of lactose intolerance.¹³ However, many people who have difficulty digesting milk find that they can digest yogurt. This is because beneficial bacteria in yogurt have lactase activity and thus help in lactose digestion.¹⁴

Gastric Cancer
It has been postulated that probiotics may help in gastric cancer prevention, but the evidence so far is mainly based on experimental in-vitro data. For instance, a study was conducted on fermented milk containing Propionibacterium freudenreichii as microbiota, and it was demonstrated that this probiotic fermented milk had pro-apoptotic effects on human gastric cancer cells.¹⁵

Potential Mechanisms

Probiotics, such as lactic acid bacteria, are active bacterial cultures with unique characteristics that allow them to survive in the gastrointestinal tract and compete with other enteric microorganisms. Thus, they help to maintain the natural balance of the microbiota and overall health.^2,3

Additionally, probiotics may promote immunomodulation by attaching to gut epithelial tissue, interacting with the immune system and producing antimicrobial substances.^2,3 Dairy lactobacilli, as part of a regular diet, may also modulate innate immune responses.^16,17 Furthermore, probiotics may suppress the growth of bacteria that convert procarcinogens into carcinogens.¹⁸

Conclusion

Evidence suggests that probiotic milk products enhance digestive and overall health by improving gut microbiota and promoting immunity. These products may be beneficial in Helicobacter pylori infection and irritable bowel syndrome and could prevent antibiotic-associated diarrhea.

Further research, including large randomized controlled trials and long-term cohort studies, is needed to confirm these findings. As well, more research is needed to elucidate the role of probiotic milk products in lactose intolerance and gastric cancer.

For more information, see the article Gut Microbiota and Milk Products: Implications for Health.

Emerging evidence from systematic reviews and randomized controlled trials suggests that milk product consumption does not have an adverse impact on inflammation. In fact, milk and milk products may reduce inflammation in the body by improving levels of inflammatory biomarkers.

Systemic inflammation is a recognized factor in the development of atherosclerosis. Increased levels of certain inflammatory biomarkers, including C-reactive protein, IL-6 and TNF-α, have been associated with an increased risk for cardiovascular diseases.¹

In the past few years, several studies, including systematic reviews and randomized controlled trials, have investigated whether milk product consumption may have an effect on inflammation in the body. Some studies have shown that milk products may beneficially impact inflammatory processes.

The role of milk products against inflammation appears to be mediated by certain components such as:

• vitamin D,
• calcium,
• bioactive peptides.

In addition, the beneficial impact of milk products on weight management may also play a role given the link between obesity and inflammation.^2,3

The Evidence

A 2013 systematic review of eight randomized controlled nutritional intervention trials found that milk products do not have adverse effects on biomarkers of inflammation among overweight or obese adults.¹

• In one study, which looked at inflammation as a primary outcome, dairy consumption improved pro- and anti-inflammatory biomarker concentrations;
• Among seven studies that looked at inflammation as a secondary outcome, three demonstrated improvements in key inflammatory biomarkers, namely C-reactive protein, IL-6 and TNF-α, after milk product consumption;
• Four other studies did not find an association between milk products and inflammatory biomarkers;
• The conclusion from this systematic review is that milk products have either a neutral or beneficial impact on inflammation.

Another systematic review, also published in 2013, evaluated how certain dietary patterns may affect the biomarkers of low-grade inflammation. The study showed that low-fat milk products were positively associated with improvements in the anti-inflammatory biomarker adiponectin.⁴

Additionally, in a randomized cross-over trial of 12 overweight or obese Australians, the effects of different diets rich in dairy products on circulating inflammatory and pro-atherogenic biomarkers was evaluated. A low-fat dairy diet was compared with 2 full-fat dairy diets (one containing mainly fermented products such as yogurt and cheese and the other containing non-fermented products such as butter, cream and ice cream). Each full-fat dairy diet was assigned for 3 weeks. Subjects followed the low-fat diet twice for 2 weeks, between the full-fat dairy diets and at the end of these dietary periods.⁵

• The participants in the low-fat dairy diet group did not show a more favourable impact on inflammatory markers;
• No significant differences were observed between the full-fat fermented and non-fermented diets.

A single-blinded randomized controlled trial of 31 post-menopausal women was conducted to investigate the potential influence of dairy vs. soy intake on local markers of inflammation. Each group was assigned 3 servings of dairy or soy beverage daily for 28 days.⁶

• There was no significant difference in inflammatory markers between those who consumed dairy vs. those who consumed soy beverage, suggesting a similar protective effect.

Furthermore, a double-blind randomized controlled trial was carried out over 12 weeks among 90 males and females aged 30 to 60 with type 2 diabetes. Subjects were randomized to a plain yogurt drink, a vitamin D-fortified version, or a vitamin D/calcium-fortified version.⁷

• Significant decreases were observed in inflammatory markers, namely high-sensitivity C-reactive protein, IL-1, IL-6, fibrinogen and retinol binding protein-4 for both the vitamin D-fortified and the vitamin D/calcium-fortified yogurt drink;
• The anti-inflammatory biomarker adiponectin was significantly improved in the vitamin D/calcium-fortified group compared to the vitamin D-fortified group.

In a single meal study, the potential effect of full-fat milk products (cheese, yogurt, butter and cream) on circulating inflammatory biomarkers was investigated among 13 overweight participants in 5 test meals.⁸

• It was found that full-fat milk products did not increase biomarkers related to inflammation and atherogenesis;
• Significant reductions in levels of inflammatory biomarkers were observed 3 hours post-consumption of cream and butter.

The Health, Aging and Body Composition (Health ABC) study is a prospective cohort study of adults aged 70 to 79 years. Dietary patterns in relation to systemic inflammation were evaluated among 1,751 participants. The results showed that a dietary pattern high in low-fat milk products, whole grains, poultry, fish and vegetables may be associated with lower systemic inflammation among older adults.⁹

The ATTICA study is a health and nutrition survey that was conducted in Greece on 1,518 and 1,524 healthy men and women. An inverse association between milk product consumption and levels of various inflammatory markers, namely C-reactive protein, IL-6 and TNF-α, was found.¹⁰

Potential Mechanisms

The mechanisms by which milk products could potentially affect systemic inflammation are poorly understood. Vitamin D, present in fortified milk, has anti-inflammatory properties and may modulate the effect of certain pro-inflammatory cytokines.⁷ Calcium in milk may also suppress inflammatory stress and enhance the anti-inflammatory action of vitamin D.^7,11

Milk also contains bioactive peptides such as angiotensin-converting enzyme inhibitory peptides. These inhibit the stimulation of the renin-angiotensin system, thereby suppressing inflammatory responses.¹¹

Furthermore, milk products have been associated with improvements in body composition and a reduction in adipose tissue.^12,3 Since excess adipose tissue has been associated with increased inflammation, it is possible that milk products may act against inflammation via their role in weight management.^2,3,11

For more information, read Healthy Weight: Research Synopsis.

Conclusion

Milk and milk products do not appear to have an adverse effect on inflammatory biomarkers. In fact, there is evidence to suggest that milk product consumption may actually be beneficial against systemic inflammation.

More research is needed to confirm these findings and assess whether different types of milk products may have different effects.

Mechanistic studies are also required to elucidate the mechanisms by which milk products may improve biomarkers of inflammation.

It is well known that vitamin D influences the development and maintenance of bone mass and reduces the risk of osteoporosis. Furthermore, it is also thought to improve lower limb neuromuscular function.

Introduction

Vitamin D from food, supplements and sun exposure is first transformed in the liver into 25‑hydroxyvitamin D [25(OH)D] and is then activated in the kidneys as 1,25-dihydroxyvitamin D or calcitriol.¹ This hormonally active form is responsible for the homeostasis of calcium and phosphorus, whereas serum 25(OH)D concentrations reflect vitamin D status.² Serum 25(OH)D concentrations and intakes of vitamin D (from both food and supplements) may be significantly and positively associated with bone mineral density (BMD).^1,3

Aging leads to a loss of bone mass and decreased vitamin D synthesis, which may contribute to the development of osteoporosis. Inadequate intake of calcium and vitamin D may aggravate the situation and increase the risk in particular of vertebral, hip and forearm fractures.¹ Osteoporosis is more common in women than men⁴ due to decreased concentrations of estrogen at menopause, which promote a reduction in BMD.

The beneficial effects of vitamin D on the absorption and use of calcium and phosphorus, its contribution to the development of solid bones, and its ability to reduce the risk of osteoporosis are recognized by different health authorities, including Health Canada, the U.S. Food and Drug Administration (FDA), the Institute of Medicine (IOM) and the European Food Safety Authority (EFSA).¹ According to these agencies, data support the conclusion that there is an independent cause-and-effect relationship between calcium and vitamin D intakes and the growth, development and maintenance of bones and teeth, and a reduced risk of osteoporotic fracture.

The Evidence

After conducting a comprehensive review of the evidence to date, the IOM found data suggesting that there is a dose-dependent association between 25(OH)D concentrations and bone mineral content in children over the age of 6 months, adolescents, and adults (both younger and older) of different ethnic origins.¹ A vitamin D serum concentration of 50 nmol/L was deemed to be sufficient to ensure bone health outcomes.¹

Data have also demonstrated that treatment combining a vitamin D supplement and a calcium supplement may also reduce bone loss and may lead to a greater increase in BMD compared to treatment without vitamin D.⁵ Vitamin D may also improve lower limb neuromuscular function and decrease the frequency of falls.⁵

The results of a 2010 meta-analysis of 8 studies indicate that combined vitamin D and calcium supplementation can decrease the incidence of nonvertebral fractures by 23% and hip fractures by 30%.⁶

• This supplementation may also reduce fractures other than hip fractures to a greater degree compared to calcium supplementation alone;
• Fractures of the hip and vertebrae seem to be more frequent among older people with deficient intakes of vitamin D and calcium, whereas other fractures are more common among people who are older but who are active and who have higher intakes of these two nutrients.

A 2009 meta-analysis of 20 randomized controlled trials on fractures in people over the age of 65 showed that vitamin D supplementation of more than 482 IU per day reduced nonvertebral fractures by 20% and hip fractures by 18%.⁷

• The reduction in nonvertebral fractures was greater when higher doses of vitamin D were used;
• In terms of supplementation with doses below 400 IU, no decrease in hip fractures was observed;
• The addition of calcium to the vitamin D supplementation did not influence the reduction of nonvertebral fractures;
• Cholecalciferol (D₃) seems to be more effective than ergocalciferol (D₂) at decreasing fractures, as, at an equivalent dose, it seems to increase 25(OH)D levels to a greater degree because of greater vitamin D receptor affinity.

Another meta-analysis of randomized controlled trials indicated that vitamin D supplementation in people at risk of hip fractures (postmenopausal women or men aged 50 years and over) reduced the risk of hip fractures by 18% only when the supplement was combined with calcium.⁸

Similarly, a meta-analysis of 45 studies revealed that combined supplementation with 400 to 800 IU of vitamin D and 1,000 mg of calcium per day reduced the incidence of hip fractures by 16%.⁹ However, this effect may be greater for individuals whose daily intakes of vitamin D are below 400 IU. Furthermore, vitamin D supplements alone and those that combined both vitamin D and calcium were less effective at preventing fractures than calcium supplements alone.⁹

Potential Mechanisms

Vitamin D regulates blood calcium levels by improving the intestinal absorption of calcium and minimizing its elimination in the urine. It also plays a role in the deposit of calcium in bone and the removal of calcium from bone to meet the body's needs.¹ A vitamin D deficiency results in a low absorption of calcium and elevated concentrations of parathyroid hormone (PTH), a hormone that acts to increase blood calcium levels by releasing calcium from the bones.¹⁰

Over the long term, vitamin D deficiency leads to a loss of bone mass, which weakens the bones and causes osteoporosis. Adequate vitamin D intake decreases bone loss by reducing the secretion of PTH and prevents excessive bone remodelling (bone turnover). Several data show that high bone remodelling rates increase bone fragility.¹ Furthermore, this rate doubles across menopause and triples by the age of 65 years.

Conclusions

Vitamin D plays a role in helping people reach and maintain adequate BMD. Some populations, such as children who present with a vitamin D deficiency and seniors living in long-term care facilities, would benefit more from vitamin D supplementation. The dose of vitamin D required to reduce the incidence of fractures is controversial. In studies that showed evidence of decreased fractures in seniors, a minimum dose of 400 IU of vitamin D was required.

To ensure the maintenance of bone health, the IOM recommends a serum 25(OH)D concentration of 50 nmol/L. However, some experts suggest that concentrations should be above 75 nmol/L.^1,11 These concentrations would limit bone resorption and demineralization by preventing an increase in PTH levels. As a preventive measure, Health Canada recommends that all adults over the age of 50 years take a daily vitamin D supplement of 400 IU.¹ However, Osteoporosis Canada suggests that adults under the age of 50 years take a supplement of 400 to 1,000 IU per day and that people over the age of 50 years or younger adults at higher risk of osteoporosis take a supplement of 800 to 2,000 IU per day.¹⁴

Increasing childhood obesity rates have made food intake at school a focal point for policy makers, school administrators, parents, and the media. Flavoured milks are being limited or even eliminated from some schools in Canada and the U.S. … with unintended consequences that could critically hinder optimal nutrient intakes.

The American Heart Association’s Scientific Statement on the role of dietary sugars in cardiovascular health concluded that the form in which added sugars are consumed is an important factor. Adding sugar to nutrient-rich foods (e.g., flavoured milk and yogurts) improves diet quality in children and adolescents and has no adverse effects on weight.¹

A NHANES study (n=7557 children and adolescents) conducted from 1999 to 2002 showed that:

• those who drank flavoured milk reported significantly higher total milk intakes than consumers of plain milk only (p<0.05)
• sugar intakes were similar among plain milk drinkers, flavoured milk drinkers and non-milk drinkers
• vitamin A, calcium, phosphorus, magnesium, and potassium intakes were significantly higher in milk (flavoured or plain) drinkers compared to non-milk drinkers (p<0.05); and
• BMIs of individuals who consumed milk (flavoured or plain) were equal to or lower than those of non-milk drinkers (p<0.05).²

Flavoured milk provides the same essential nutrients as plain milk and is a popular beverage choice for children, accounting for more than two thirds of milk chosen at school lunches.³ Furthermore, the estimated contribution of added sugars from flavoured milk, derived from per capita availability data, is low at <1 g/day, or ~1% of Canadians’ total added sugars intake.⁴

When flavoured milks are eliminated from schools, the impact is significant. In our recent study, milk consumption dropped 47% when chocolate milk was eliminated from six elementary schools in the greater Saskatoon area.⁵ Similarly, in a U.S. study that included 49 American elementary schools that stopped offering flavoured milks there was a ~37% decrease in milk consumption.³ Alternate foods to replace the lost nutrients due to reduced milk consumption would require three to four additional foods and result in higher intakes of calories and fat.³

According to the latest national survey of Canadians, ~37% of children and up to 87% of adolescents do not meet the minimum recommended intakes of milk products.⁶ Flavoured milks, such as chocolate milk, provide another option to help meet recommended intakes of milk products.