Dr. Sharma's Obesity Notes » blog

Obesity in Indian Girls and Women

Arya M. Sharma, MD — Wed, 22 May 2013 13:00:26 +0000

During my current visit to New Delhi, it is hard to overlook the substantial increase in the prevalence of obesity in Indian men and women. While this may not be the phenotype that immediately comes to mind when thinking of India, there is no doubt that obesity prevalence is continuing to rise at an alarming rate.

Recent evidence for this comes from a study published by Chopra and colleagues from New Delhi, published in a recent issue of the European Journal of Clinical Nutrition.

In this systematic review of obesity in Indian girls and women were found to have consistently higher obesity rates than Indian boys or men.

Interestingly enough, abdominal obesity, sometimes referred to as ‘male-pattern’ obesity is in fact more common in Indian women than in men.

Not surprisingly, this increased rate of obesity is reflected in an increasing prevalence of type 2 diabetes that was reported to be as high as 14% in the 2001 National Urban Diabetes Survey.

Clustering of cardiovascular disease risk factors was further increased in post-menopausal women, not least due to a number of factors that may be of particular relevance in Indian women including sedentariness and overly caloric diets.

How exactly these increasing rates of obesity can be addressed remains anyones guess. While it is easy to see the proliferation of “slimming-centres” and “spas” at every corner, as in the West, these centres often provide little long-term help and of course generally do not cater to the folks, who would likely benefit the most.

Needless to say, the medical system in India, is as overwhelmed and insufficiently prepared to address obesity, as we are in the West.

Clearly a challenge if I ever saw one.

AMS
New Delhi, India

Milk Consumption and Obesity in India

Arya M. Sharma, MD — Tue, 21 May 2013 13:00:11 +0000

I am currently in New Delhi enjoying daytime temperatures of 45 degrees Celsius – I’d forgotten how hot this can be.

A good opportunity to take a look at recent literature on obesity in India, where this is clearly becoming an increasing problem – India now has the largest number of people with obesity (using the South Asian definition of BMI 25) and perhaps the most people living with diabetes anywhere in the world.

An article that caught my eye is the recent analysis of the relationship between the consumption of milk and milk products and obesity by Satija and colleagues from the Public Health Foundation of India, New Delhi, published in PLoS One.

As anyone familiar with Indian cuisine is well aware, milk in its various forms including plain milk, in tea (where tea leaves are traditionally boiled at length in watered down milk), curd, and buttermilk (often consumed as lassi) is considered a staple of the Indian diet and apart from lentils (another staple), often the only significant source of protein for the vegetarian masses.

Information on dairy consumption assessed using a Food Frequency Questionnaire was obtained from the cross-sectional sib-pair designed Indian Migration Study (3698 men and 2659 women), conducted at four factory locations across north, central and south India.

After controlling for potential confounders, the risk of being obese (BMI≥25) was almost 50% lower among women among those who consume one or more portions of plain milk daily than those who did not consume any milk.

On the other hand, daily tea consumption of more than one portion was associated with a 50% increased risk of obesity and increased waist circumference in men but not among women.

There was no association between curd and buttermilk/lassi consumption with obesity and high waist circumference among either men or women.

Thus, there appears to be an inverse association between the daily consumption of plain milk with the risk of being obese, but the authors hasten to add that this is merely an association and does not imply causality. In plain english, this means that we should not rush to conclusion that decreased milk consumption should be added to the list of possible causes of obesity in South Asia or that drinking more milk will help my Indian brethren lose weight.

On the other hand, given that there are several reasonable hypotheses linking adequate dairy intake to energy homeostasis, this is certainly an issue that may require further study.

I do recall that my grandfather, who lived to be a 104 and was always thin as a rail, would never go without his daily glass of warm milk before bedtime (but he’d also go for long brisk walks at 5 am every morning – so no conclusions can be drawn from this n=1 case study).

AMS
New Delhi, Arya

To Salt or Not To Salt?

Arya M. Sharma, MD — Mon, 20 May 2013 13:00:11 +0000

Unbeknownst to many readers, the first 10 years of my research career was built largely on studying the effects of salt (or rather sodium chloride) on blood pressure.

In over 40 peer-reviewed publications, we described in excruciating detail the physiological effects of increasing and decreasing sodium intake, in many cases using single-blind randomised trial designs in hundreds of volunteers.

We not only examined the effects of salt on blood pressure but also on a wide range of physiological, metabolic and psychological parameters. We studied the effects on acid-base balance, we conducted genetic studies, we even performed in vitro studies on cells cultured from “salt-sensitive” and “salt-resitant” individuals.

In many respects, these studies left me as confused about the role of sodium on these parameters as I was before. Not that we did not report findings that helped us better understand the complex physiology of sodium homeostasis – it is just that we failed to convincingly demonstrate any major health implications of these findings. In some cases we even reported adverse consequences of sodium restriction resulting both in significant elevations in plasma lipids and insulin resistance (perhaps not surprising given that reducing sodium intake markedly stimulates both the sympathetic and renin-angiotensin systems – the very systems we seek to block to reduce cardiovascular risk).

That was almost 20 years ago – the field does not appear to be much clearer today.

Thus, although surprising to some, I must admit that I was by no means surprised by the report on sodium released last week by the Institute of Medicine, with the rather revealing conclusion that,

“…the evidence from studies on direct health outcomes was insufficient and inconsistent regarding an association between sodium intake below 2,300 mg per day and benefit or risk of CVD outcomes (including stroke and CVD mortality) or all-cause mortality in the general U.S. population.” (or any other population for that matter)

This is not to deny that despite considerable methodological problems (not least in the actual measurement of salt intake), there is evidence to support the idea that higher salt intake may affect blood pressure and possibly cardiovascular risk. However, the data is certainly far less conclusive than food bloggers and health activists would lead us to be believe.

Not surprisingly, the same activists and organisations are now up in arms stopping just short of criticizing the scientific credibility of the IOM expert committee – no doubt, the same folks would have been applauding the conclusions of this “illustrious panel”, had the findings been more in line with their own activist agendas.

What is perhaps even more infuriating to those who have always considered the issue of sodium recommendations a slam-dunk case is the statement by the IOM that, there is in fact no basis on which to draw recommendations for the general public in recognition of the fact that significant proportions of the population may require higher sodium intakes and may even be likely to suffer harm from overly enthusiatic sodium restriction.

While I have no illusions that this report will in any way put the century old debate to rest (indeed the report calls for further research), I think that there is a much bigger message in this report that should let us tread cautiously when it comes to dietary recommendations in general.

Let us remember that associations (on which so many of our assumptions about healthy diets depend) simply do not prove causality, even when backed by seemingly plausible biological hypotheses derived largely from rodent toxicology. We should also remember that fancy statistical predictions on the vast number of lives lost or saved by altering the population intake of this or the other nutrient, are generally based on sometimes rather heroic assumptions that may well explain whey they are rarely (if ever) borne out by actual interventions.

Thus, whether we are talking about salt, fat, carbs, sugar, fibre, gluten, calcium, Vit D, dairy or red-meat, a degree of humility in advocating for policies and other measures to reduce or increase this or the other is generally in order.

Seldom in the field of nutrition are things as cut and dried as some will have us believe – if only food were as simple as tobacco.

AMS
New Delhi, India

Disclaimer: I was invited to be on the IOM Expert Committee but had to decline due to other obligations.

Obesity Weekend Roundup, May 17, 2013

Arya M. Sharma, MD — Sun, 19 May 2013 13:00:10 +0000

As not everyone may have a chance during the week to read every post, here’s a roundup of last week’s posts:

Have a great Sunday! (or what is left of it)

AMS
Frankfurt, Germany

Obesity & Energetic Offerings, May 17, 2013

Arya M. Sharma, MD — Sat, 18 May 2013 13:00:52 +0000

David Allison, PhD, Distinguished Professor, University of Alabama

For several months now, my colleagues at the University of Alabama have been compiling a weekly list of selected obesity related articles in a list they call Obesity and Energetic Offerings.

The list is compiled by David B. Allison, Michelle Bohan-Brown, Emily Dhurandhar, Kathryn Kaiser, and Andrew Brown.

The following is a selection of articles from this week’s list that caught my attention – - the link headings are theirs, not mine:

Findings Contrary to Hypotheses or Popular Ideas

Aging

Basic Science

Clinical

Commentary

Dietary Fat

Food

Gut Microbiota

Methods

Neighborhoods

Physical Activity

Policy Related

Psychology

Research Reproducibility and Integrity

Salt

Stigma

Sugar, SSBs, and related

Surgery

For a complete list and to directly join this list, please click here.

AMS
Edmonton, Alberta

Prohibition Drives Fast Food Underground?

Arya M. Sharma, MD — Fri, 17 May 2013 13:00:03 +0000

Not quite, although this does make for a good headline.

The actual story, which accompanies the global media reports of the underground smuggling operation that illegally routes KFC contraband to Gaza, however does illustrate the lengths to which people will go to obtain their crunchy fat, salt and sugar fix.

The report in the International Herald Tribune describes the distance KFC has to travel as,

“…a journey that involved two taxis, an international border, a smuggling tunnel and a young entrepreneur coordinating it all from a small shop here called Yamama — Arabic for pigeon.”

According to this report, the entrepreneur, a Mr. Efrangi (aka “the Kentucky guy”),

“..has coordinated four deliveries totaling about 100 meals, making about $6 per meal in profit. He promotes the service on Yamama’s Facebook page, and whenever there is a critical mass of orders — usually 30 — he starts a complicated process of telephone calls, wire transfers and coordination with the Hamas government to get the chicken from there to here.”

While the report focuses on the “resilience” of the Gaza inhabitants, who are merely seeking to live a “normal life”, the story does speak to the lengths that people will go still their “cravings”.

While Mr. Efrangi, for logistical reasons, limits his orders to chicken pieces, fries, coleslaw and apple pie, he may not be in business for long.

As the Tribune reports,

“A Gaza businessman who asked to be identified only by his nickname, Abu Ali, to avoid tipping off his competitors, said he applied for a franchise from KFC’s Middle East dealer, Americana Group, two months ago. Adeeb al-Bakri, who owns four KFC and Pizza Hut franchises in the West Bank, said he had been authorized to open a restaurant in Gaza and was working out the details.”

Throughout human history, people have desired what is most difficult to get – bans and prohibitions have always made stuff more worth having than before (whilst upping the “cool-factor”) – apparently, junk food is no exception.

As an interesting side note, which perhaps speaks to the “addictiveness” of the KFC formula, some readers may recall that KFC (now belonging to PepsiCo) was at one time owned by R.J. Reynolds (now RJR Nabisco) – the makers of Camel, Pall Mall, Winston and other “choice tobacco products”.

AMS
Edmonton, AB

Restoring Energy Balance in Communities

Arya M. Sharma, MD — Thu, 16 May 2013 13:00:24 +0000

Professor Shiriki Kumanyika, University of Pennsylvania, Philadelphia

Based on the simplistic notion that excessive weight gain is merely a matter of calories-in and calories-out, conventional individual-level approaches to obesity have long focussed on restoring energy balance in individuals by attempting to influence energy intake and output (with rather modest success).

What affects weight gain in individuals, may well also influence weight gain in populations, at least that is the underpinning idea of the ecological approach to addressing obesity. But, as in individuals, interventions based on this notion are far from straightforward to implement or sustain.

This may well be, because, as at the individual level, complex sociocultural and psychological (not to mention biological) factors tend to occur that serve to push the energy balance towards the positive side of the equation – this is particularly true for minority and marginalised populations.

Thus, as presented by Shiriki Kumanyika from the University of Pennsylvania at the 20th European Congress on Obesity in Liverpool, social inequalities can make certain population seqments particularly vulnerable for obesogenic factors.

In this context, she emphasised that the term “vulnerability” itself can be discriminating and should be clearly defined in the context of social inequalities that face certain population groups (e.g. ethnic minorities) rather than in terms of “deficits”.

In her talk, she presented an overview of her work demonstrating the markedly increased obesity rates in black women, American Indians and Mexican Americans in the US. As she noted, even in the context of clinical trials, not only do participants from these groups show less weight loss with interventions but also gain weight more rapidly when randomised to the control group.

While the nature of foods and activity options available to whose with limited resources accounts for some of the increased risk, it turns out that higher income does not appear to be protective early in the nutrition-economic transition. Rather, during this transition phase, upward mobility may actually further increase the risk of obesity as behavioural risks (increased caloric intake, sedentariness) become more “affordable”.

In order to better understand these patterns of differences in ethnic minorities, a network consisting largely of black American researchers, has developed a “Community Energy Balance” framework.

At the community level energy balance is mediated through the many factors that directly or indirectly affect food intake and physical activity.

This framework leads to the identification of a wide range of potential intervention targets at the levels of the community, family and individuals.

Other elements of this framework also consider cultural-contextual influences that influence obesity including historical experiences and adaptations, type of minority status, structural influences, and sociocultural influences.

The hope is that although both socio-economic status and ethnic differentials are important, this framework will facilitate a systematic analysis and identification of possible solutions to the inequalities that affect these minority populations.

However, whether or not such interventions will prove more effective in communities than current individual-based interventions clearly remains to be seen. Knowing the intrinsic property of complex systems (including communities) to often respond and adapt in unpredictable ways, often with unintended consequences, it is by no means clear as to which community based approaches to addressing inequalities or other drivers of obesity will ultimately tip populations towards the negative side of the energy balance equation.

AMS
London, UK

Developments in Obesity Treatment Session, ECO 2013

Arya M. Sharma, MD — Wed, 15 May 2013 13:00:05 +0000

This morning, on the last day of the 20th European Congress on Obesity in Liverpool, I attended a session that looked at clinical outcomes in obesity management.

The first talk, given by Karlson from Norway looked at predictors of weight-loss outcomes in about 200 individuals undergoing a program that included several week-long in-patient stays at a rehabilitation centre over the course of a year with follow-up “maintenance” provider-patient contacts. Although the average weight loss at 12 months was only around 10 Kg, the variability in weight-loss response increased, with a substantial number of patients achieving weight loss comparable with bariatric surgery, while others regained much of the initial weight loss. In their analyses, initial weight loss, type 2 diabetes, mental health related quality of life, younger age and employment status were the strongest predictors of success. The other variable that influenced outcomes appeared to be the frequency of visits to the patients’ family doctors.

This was followed by a presentation by Nick Finer (London, UK), who reviewed the improvements in blood pressure in patients treated with the combination of phentermine and extended-release topiramate (marketed by Vivus Pharmacetuicals in the US as Qsymia®) in the CONQUER trial, a 56-week double blind placebo-controlled RCT. Overall, treated individuals experienced approximately 7 mmHg average fall in systolic blood pressure that was sustained over the year of treatment. Irrespective of hypertension status about a third of treated patients achieved a rather impressive greater than 15% weight loss. Not surprisingly, those who lost the most weight, experienced the greatest reduction in blood pressure (-10/-6 mmHg), despite reduction in blood pressure medications in a substantial number of hypertensive patients. Thus, there is no doubt that treatment with PT/TPM combination can result in substantial improvement in blood pressure control, that appear directly related to the degree of weight loss.

Ed Hendricks (US) addressed the issue of whether or not phentermine is actually addictive, a notion that is largely based on similarities in molecular structure of phentermine with amphetamines. Based on a prospective observation of 72 patients treated with rather high doses of phentermine (50+ mg/d) for at least 12 months, who agreed to discontinue their phentermine for 48 hours, there was no evidence for “withdrawal” based on a modified Amphetamine Withdrawal Questionnaire, with the exception of recurrence of hunger (as one might expect). Thus, these findings do not support the notion that abrupt discontinuation following the long-term use of phentermine results in phentermine “dependency” or “addiction”.

William Shanahan, Chief Medical Officer of Arena Pharmaceuticals talked about how treatment with lorcaserin, which will become available for obesity treatment in the US in June (Belviq®), results in a significant decrease in Framingham general cardiovascular risk scores, especially in men. Again, the greatest reduction in risk scores were seen in the patients with the greatest degree of weight loss response on lorcaserin.

Kyra Sim, from the University of Sydney, Australia, described substantial cost savings of obesity treatment in women seeking fertility treatments. This prospective randomised controlled trial included 49 women willing to undergo a three-month weight-loss intervention program using VLCD for 6 weeks followed by a moderately calorie-deficit diet and exercise recommendations. Mean weight loss in the intervention group was about 7%. Fertility rates were 48% in the intervention group vs 18% in the control group – in addition, the cost of each live baby in the intervention group was about one-third in that of the control group.

Marina Reeves, from the University of Queensland, Australia, discussed the issue of substantial weight gain commonly seen in women who survive breast cancer (fortunately, an increasing proportion of women with BC). 90 women with a 1st diagnosis of stage 1-111 breast cancer were enrolled in either a behavioural intervention that involved telephone counselling aiming for a 5-10% weight loss or a usual care group. At 6 months, women in the intervention group (which had a 20% drop out rate), lost about 5% of body weight and showed some increase in moderate to vigorous physical activity, and improvements in fatigue. Overall these findings speak to the feasibility of conducting a larger prospective study to examine the impact of this intervention on longer-term outcomes in breast cancer survivors.

AMS
Liverpool, UK

Disclaimer: I have previously received honoraria for consulting from both Arena and Vivus

Nudge, Nudge – Wink, Wink: Changing Health Behaviours

Arya M. Sharma, MD — Tue, 14 May 2013 13:00:45 +0000

Theresa Marteau, Director Behaviour and Health Research Unit, University of Cambridge

The second morning of the 20th European Congress on Obesity here in Liverpool was kicked off by a presentation by Theresa Marteau, Cambridge Institute of Public Health, on the use of “choice architecture” to “nudge” individuals towards adopting healthier behaviours.

Given the limited effectiveness (some may say “failure”) of attempts to change population behaviours based on conscious, goal directed, reflective interventions, “nudging” attempts to change behaviours through non-conscious, habitual or automatic interventions.

The idea of nudging, defined by Thaler and Sunstein as

“..any aspect of the choice architecture that alters people’s behaviour in a predictable way without forbidding any options or significantly changing their economic incentives”,

is not a new idea to social psychologists and is based on the observation that our conscious processes are finite and that most of our responses to the environment occur below our conscious awareness.

Thus, while previous approaches to changing health behaviours have primarily focussed on conscious cognitive approaches, newer models attempt to change behaviours by targeting the sub-conscious non-reflective processes that underly these behaviours.

In her talk, Marteau described the results of a large-scale scoping review on use of nudging interventions for tobacco-, alcohol-, diet- and physical activity-related behaviours. Her analysis included ~350 articles describing two types of interventions that altered either the properties (ambience, functional design, labelling, presentation, sizing) or placement (availability, proximity) of objects or stimuli within the micro-environent where the behaviour is happening. In addition the analysis looked at priming and prompting interventions.

All of these approaches have in common that they typically require minimal cognitive engagement and can potentially influence many people at the same time. In addition, health nudging, by avoiding the use of literacy and numeracy, may be able to reduce social patterning thus reducing health inequalities.

To date, most of the work on nudging has been done in the context of dietary behaviours, mainly on food labelling and sizing.

As one may expect, studies in experimental settings have shown effects of ambience (e.g. effects of the tempo of music on speed of eating), functional design (e.g. change in packaging), labelling (e.g. use of exciting names or cartoon characters on healthier foods), proximity (e.g. product placement on the shelf), or prompts (e.g signs or announcements) on behaviours.

Thus, for example, ongoing research suggests that simply putting healthier foods at the ends of aisles changes shopper behaviours largely independent of pricing, suggesting that simply changing the placement of foods may be far more effective than changing pricing (e.g. taxation).

The big question, however, is whether these effects are indeed sustained and have large enough effect sizes. So far, the data on this is not clear, which is why Marteau and colleagues are currently working on a synthesis of evidence to see whether such nudging interventions do indeed influence health behaviours outside the laboratory.

In the real world, healthy nudges have to compete with unhealthy nudges – e.g. images or labels warning against overconsumption of fast food have to compete with the strong nudges created by the common association of fast food advertising and images with sporting events – this may well be an insurmountable obstacle given the almost limitless tool box and financial resources of the food industry.

Marteau also addressed the acceptability of nudging interventions. As one may expect, less intrusive interventions such as placing or health prompts were found to be far most acceptable than taxing, pricing, or limiting portion size, which are generally seen as overtly limiting choice.

Ultimately, the issue of acceptability will be the rate-limiting-step for legislators, who need to align public and political wills. This is something that is unlikely to happen without stronger evidence to support broad acceptability of such measures. Countermeasures by industry and the voices of those who oppose coercive paternalism will clearly further limit political enthusiasm for legislative interventions.

On a happier note, Marteau notes that there may be somewhat greater acceptance for choice architecture interventions in children and young people.

Whether or not her optimism is warranted, remains to be seen.

AMS
Liverpool, UK

Follow live tweets from this conference with #ECO2013

Skeletal Muscle as an Endocrine Organ

Arya M. Sharma, MD — Mon, 13 May 2013 13:00:46 +0000

Prof. Bente Klarlund Pedersen, University of Copenhagen

This week, I am attending the 20th European Congress on Obesity in Liverpool.

The opening plenary lecture this morning was presented by Bente Pedersen from the University of Copenhagen, who reviewed her work demonstrating that the profound positive effects of exercise on metabolism, inflammation, mood and cognitive function are mediated by 100s of proteins secreted from skeletal muscle cells in response to muscle contraction.

These molecules are now referred to as “myokines” and have been shown to exert either autocrine, paracrine or endocrine effects on other organs like adipose tissue, liver, pancreas, bones and brain..

This exciting area of research is nicely summarized in a recent paper by Bente Pedersen and Mark Febbraio published in Nature Endocrine Reviews.

For example, exercise-induced increases in myocellular production of BDNF and IL-6 can increase AMPK-mediated fat oxidation, whereby IL-6 appears to have systemic effects on the liver, adipose tissue and the immune system and even mediates crosstalk between intestinal L cells and pancreatic islets.

Other myokines (e.g. the osteogenic factors IGF-1 and FGF-2; FSTL-1) can improve the endothelial function of the vascular system.

More recently, the myokine irisin, has been shown to promote “browning” of adipose tissue.

Other lines of research suggest that myokines can influence the growth of cancer cells as well as modulate immune function, bone development and pancreatic B-cells.

Current research using proteomic techniques will likely provide further insights into the hundreds of molecules secreted from skeletal muscle in response to physical activity and explain how these myokines mediate the wide-ranging beneficial effects of exercise and the detrimental effects of sedentariness on many chronic diseases.

AMS

Liverpool, UK

You can follow live tweets from the conference at #ECO2013