Matt Metzgar

Book Review: The Perfect Health Diet

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.

Exercise Increases Food Reward?

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.

Eating in Front of the Computer

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

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

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.

 

Grain Paper Published

My new paper, "Externalities from Grain Consumption: A Survey" has just been published in the International Journal of Food Sciences and Nutrition.

Overweight/Obesity in Preschoolers

 
I was going to title this post, "Depressing News of the Day", because that's what this finding is for me.  There is an alarming increase in overweight/obesity for preschoolers on a global scale.  This increase is now happening in both developed and developing countries, and across all racial groups.

The paper doesn't really go into the causes except to say that is likely due to changes in nutrition and physical activity.  They do point out that this is a dire problem given its future implications:

"Intrauterine, infant, and preschool periods are considered possible critical periods for programming long-term regulation of energy balance (22–24). Waiting for school programs to address this problem is probably too late."

Why Is Empirical Evidence Being Ignored?

I don't know what's going lately, but some of these blog posts I'm reading are getting farther and farther out there.  Here's the latest from Gary Taubes:

"I’m about to launch into a discussion of two hypotheses of obesity that exist in competing paradigms – the food reward/palatability hypothesis that Stephan Guyenet has revived, which lives firmly within the energy balance paradigm (calories-in>calories-out) and the carbohydrate/insulin hypothesis, which I’ve been pushing and which lives in the fat accumulation disorder/fuel partitioning paradigm."

Here's the problem: his carbohydrate/insulin hypothesis, which necessarily implies that a low-carb diet is the solution, has no empirical studies to support it for weight loss.  The one-year low-carb study showed it was no better than any other diet, and that it didn't lead to much weight loss.

Let's look at the two year study(pdf).  It took obese subjects starting at an average weight of 227 pounds, and then 2 years later they were at 213 pounds (and weight was trending upward).  How is this a success?  They are still obese! 

Yet somehow Gary takes a diet that clinical evidence shows is ineffective, and now wants to compare it to an alternate hypothesis.  Huh?  How does a hypothesis with no clinical evidence somehow get back into the argument as to what causes obesity? 

I know, I know, it works for Gary and for some other people.  But when it is tested clinically (which is the point of science to differentiate it from anecdotal evidence), it doesn't measure up.  Atkins book was published in 1972, and so now it's been almost 40 years of waiting for that clinical proof to come in.  Does anyone really believe that 40 years isn't enough time to test a hypothesis?  Does anyone believe that this is somehow the magical answer to obesity and that if it's just tested in the right way, or maybe tested one more time, or maybe if the carb count is lower, that it can transform an obese person into a normal weight person?   

Don't hold your breath.

Back From AHS Part 3

Here are a few thoughts I had on improving things for next year:

• Offer a couple awards for the top presentations, maybe $500 or $1,000  (I'm a firm believer in economic incentives.)
• In fact, you could have two awards: the top presentation as determined by audience vote, and then the top presentation determined by a presenter vote.
• Some other types of audience interaction - maybe something via cell phone or along those lines.  The technology is there for it.
• Some type of party event one night.
• Ancestral Health t-shirts, etc., for sale.
• Live video streaming (I know they tried to have it this year.)

• And finally, some pitchers of water in the main rooms.

These are just suggestions for improvement as I thought the event went very well for the first installment.

Back From AHS Part 2

A few more thoughts:

• Hopefully, that last post didn't sound too grumpy.  I pulled in last night at 1:30 am to an empty moving truck that needs filled - so it's a stressful time right now.
• Art Devany wasn't there.  I wish he would have come.  I would've liked to hear what he had to say.
• I met some readers of my blog - very cool!  I appreciate it, and it makes it seem more real than just a stat page with web hits.
• I did the best I could on my presentation.  I tried to bring something original to the mix.  It's always difficult to judge your own work, so hopefully it went over well.
• Dressing up has gone out of fashion.  I'm not sure in the logic of going to a conference and then wearing a golf shirt to present.  Maybe it's the academic in me, but that's not how I approach things.

Overall, it was a great event.  The next post I'll list some ideas to make it bigger and better next year.