Matt Metzgar

Book Review: The Perfect Health Diet

2012-02-04T20:59:25-05:00

Well, this is a partial review of the book, "The Perfect Health Diet" only because someone else said exactly what I was going to. In the book, the authors recommend a lower amount of carbs (20%), in order to keep glucose levels right below necessary levels. Here's what another reader recently said:

"Another interesting comment came from Jim Jozwiak:

Paul, this discussion gets to the crux of what I do not understand about the Perfect Health Diet. You are speaking as if refilling liver glycogen is a good thing, and it undoubtedly is, because mood is so much better when there is sufficient liver glycogen because then the brain is confident of its power supply. Also, you acknowledge that safe starch would eventually replenish liver glycogen after muscle glycogen is topped off. So why not eat enough starch to replenish liver glycogen? It is not so difficult to figure out how much that would be. Have some sugar, feel what replenished liver glycogen is like, then titrate safe starch gradually meal-by-meal to get the same effect. When I do it, and I am not an athlete, I get 260 grams of non-fiber carb per day, which is considerably more than you usually recommend. Have you tried this experiment and found the result unsatisfactory in some way?

Jim has experimented to find the amount of carbs that optimize his mood, and found it to be 260 g (1040 calories). On a 2400 calorie diet, typical for men, this would be 43% carbs.

If Peat typically recommends 180 to 250 g carbs, as Danny says, then on a 2000 calorie reference diet that would be 36% to 50% carbs.

Those numbers are strikingly similar to another statistic: The amount of carbs people actually eat in every country of the world."

So can billions of people be wrong about carbs in general? Somehow I don't think so.

I don't know how many grams of carbs I eat per day, but I'm sure it's above 150 grams. And I've noticed the same thing: if I go too low in starch, my mood suffers.

I think Peat's sugar recommendations are basically flawed, but that's another story.

I thought PHD diet was a good book, but it suffers from some flaws, primarily related to carbs. Early in the book, it says carbs above the minimum level raise blood sugar and have negative effects. Yet later in the appendix, a vegetarian version of the diet is presented saying high carbs are no problem. So which is it?

In the post I linked to, they say that if they were to rewrite the book, they would have higher carb ranges, which I believe is a step in the right direction.

Otherwise, there were some good sections about how toxins in various foods present problems. And the tone of the book is non-dogmatic, which makes for pleasant reading.

Coconut Oil and Alzheimer's Disease

2012-02-04T11:26:07-05:00

This video is from some religous network, but I thought the content was very interesting. They discuss how the ketones generated from coconut oil can help patients with Alzhemer's.

Exercise Increases Food Reward?

2012-02-03T17:31:00-05:00

This study shows how exercise may actually work against some people trying to lose weight. In the "non-responder" group, exercise increased the desire for high-fat/high-sugar foods. This effectively short-circuited the effects of exercise on fat loss.

Enjoying Nature

2012-01-28T16:55:53-05:00

Matt Metzgar

Eating in Front of the Computer

2012-01-27T19:55:34-05:00

In this study, eating lunch in front of the computer led to negative outcomes. Subjects again ate more later in the day.

"Distracted individuals were less full after lunch, and they ate significantly more biscuits in the taste test than did nondistracted participants."

"These findings provide further evidence that distraction during one meal has the capacity to influence subsequent eating. They may also help to explain the well-documented association between sedentary screen-time activities and overweight."

Eating in Front of the Television

2012-01-27T19:53:04-05:00

Following up on the last post, this study shows that eating in front of the tv leads to problems as well. One group ate lunch in front of the tv while the other did not (same meal). The group that watched tv ended up consuming more calories later on:

"These results suggest that the effects of television watching on food intake extend beyond the time of television watching to affect subsequent consumption. They further suggest that this effect may be related to an effect of television watching on encoding of the memory of the meal."

Death by Television

2012-01-27T16:31:00-05:00

I saw a newer study on television time and mortality. Here is the frightening conclusion:

"On average, every single hour of TV viewed after the age of 25 reduces the viewer's life expectancy by 21.8 (95% UI: 0.3-44.7) min. This study is limited by the low precision with which the relationship between TV viewing time and mortality is currently known. Conclusions TV viewing time may be associated with a loss of life that is comparable to other major chronic disease risk factors such as physical inactivity and obesity."

Wow! Who knows if the exact estimate is correct or not, but this suggests television viewing has a huge negative impact on health.

And I would think the new crop of large flat-screen tvs will only make this problem worse.

Fat and Sugar II

2012-01-24T21:13:11-05:00

I got a hold of that paper I mentioned a few days ago, and it's a dandy. It shows how the increase in added fats and sugars parallels the rise in obesity. The article actually tests three different hypotheses in the article: is the increase in BMI due to:

1) more fat

2) more sugar

3) more sugar and fat in combination

Both fat and sugar separately have high correlations with the increase in BMI, but fat and sugar together take the cake (pun intended!). Here's the graph:

They are getting R-squared's of 0.96, which is very high. Here's a few highlights from the paper:

"Other foods available for consumption such as dairy products, meat and eggs, vegetables, grains, and fruits were used as covariates along with fat and sugar production in multivariate regression analysis for male (female) BMI. For men, fat and sugar accounted for 96% of total variability in BMI (P < 0.001) with vegetables adding 1.5% (P < 0.001). For women, fat and sugar accounted for 97% of total variability (P < 0.001) with dairy (P = 0.0034), vegetables (P = 0.0145), and grains (P = 0.0191) each adding less than 1% to the total variability. Interestingly, dairy was negatively correlated with BMI (r = −0.86 and r = −0.90 for males and females BMI, respectively)."

In other words, they looked at the different food groups, but it was the added fat and sugar that was the primary determinant (like I mentioned in a previous post).

"The palatability hypothesis therefore predicts that increases in BMI are not due to calories per se in the drive system, but rather the increases are due to high levels of palatability that increase calorie consumption through increased stimulation of the incentive system. This leads to the hypothesis that the increased production of the additives of fat and sugar in combination would be most responsible for increased palatability and would therefore also provide the best mathematical fit for increases in calorie production and BMI over the last 30 years."

Here they are focusing on how fat and sugar in combination can produce palatable, addictive food.

Food Consumption in America

2012-01-24T20:56:27-05:00

I've been reading through a USDA publication, " Profiling Food Consumption in America(pdf)". It shows the general increase in food consumption over the past 50 years.

What's amazing is that consumption of almost everything has gone up: meats, fruits, vegetables, added fats, grains, and sugars. Take meat consumption for example. Here's the table:

(click to enlarge)

It shows an annual increase of 55 pounds of meat per person. What's driving this increase? I find it hard to believe that people were meat-deprived in the 1950s.

Most likely, I think that the increase in meat (particulary chicken) is driven by the processing of chicken - adding breading, fat, dipping sauces, etc. It may be that these added ingredients are driving the consumption of chicken (or other food groups for that matter) rather than an actual increase in the need for animal protein.

Fat Sensitivity

2012-01-21T19:28:57-05:00

I thought this looked like an interesting study. It shows how different people are either hyper or hypo-sensitive to fat intake. From the abstract:

"Hyposensitive subjects consumed significantly more energy, fat, saturated fat, fatty foods (butter, meat, dairy), had greater BMI and were less perceptive of small changes in the fat content of custard (all P < 0.05), compared to hypersensitive subjects."

"An inability to perceive low concentrations of fatty acids in foods was associated with greater consumption of fatty foods, specifically butter, meat, dairy, and increasing BMI."

My guess is a constant supply of high-fat food (like fast food) may dull the taste receptors for fat in some people.