Regular readers of this blog will have noted previous entries on the “paradoxical” reverse epidemiology of obesity and cardiovascular mortality, where risk is apparently higher in underweight compared to normal weight, overweight or even mildly obese individuals (for e.g. of previous blog entries on this click here, here or here).

Now a new Danish study by Jawdat Abdull and colleagues published in the European Heart Journal that looks at pooled data from 5 large registries with over 21,500 consecutive high-risk patients with myocardial infarction or heart failure finds essentially the same story:

After a follow-up of 10.4 years, compared with normal weight individuals (BMI 18.5-24.9) all-cause mortality was higher in underweight (BMI < 18.5) but not in overweight (BMI 25.0-29.9) or class I obese (BMI 30-34.9) individuals. Only with class II obesity (BMI 35-39.9) and higher was there a significantly increased risk for myocardial infarction and increased death risk.

This finding is very much in line with the mounting evidence that moderate overweight and mild obesity does not automatically translate into higher cardiovascular mortality in high-risk individuals with established heart disease.

As argued before, given that increased weight is a well-established risk factor for high blood pressure, diabetes, and other risk factors for cardiovascular disease, the reasons for this rather consistent “paradoxical” relationship are not clear.

Possible explanations include the idea that being underweight is a sign of general ill health and that thin people may be less able to cope with life-threatening illnesses like a heart attack at least compared to people with some extra “nutritional reserve”. Of course there are a couple of more sophisticated theories out there that to me appear highly speculative (which is why I will not mention them today).

Nevertheless, in light of this “paradox”, we may have to look beyond reducing cardiovascular morbidity and mortality to justify aggressive treatments of overweight and class I obesity with established cardiovascular disease - perhaps the aim of obesity treatment in high-risk individuals should simply be to prevent further weight gain rather than to reduce it?

I guess it would take intervention trials to find out - thankfully, these are already well underway.

AMS

Some of you may have seen the news items in yesterday’s media - a new study by Flegal et al. from the CDC, published in the Nov 7 Issue of JAMA, finds that overweight individuals (BMI 25 to <30) have significantly reduced mortality from non-cancer and non-CVD deaths and no increase in risk for death from all cancers or CVD (compared to normal weight (BMI 18.5 to <25) individuals). The results are based on an analysis of NHANES I, II & III.

I was interviewed on this paper by several media representatives and in general my take on this was:

1) BMI (a measure of weight) is a poor measure of overall health
2) More important than the amount of excess weight (especially for overweight individuals) is where it is located

Obviously, this study will lead to a lively discussion and provide to ammunition to all who claim that the obesity epidemic is being dramatized and overrated.

For us the implications are probably as follows:

1) let’s remember that weight is just a number on the scale
2) healthy eating and active living is possible (and advisable) at any weight
3) skinniness is not a guarantee for longevity

This however, should not distract us from the fact that excess weight (fat) can significantly impact on health and that therefore preventing or treating obesity in individuals where excess weight threatens or affects health is important.

Hope you’ll have time to catch the CFR,

AMS

With all the talk of “thrifty genes” and how our “hunter-gatherer genome” is overwhelmed by the “obesogenic” environment, it may be time to revisit my favorite theories about the “Natural Laws of Weight Gain“.

This is something I came up with almost 10 years ago and have used in a lot of talks over the years. I’ve always wanted to put these ideas into a book but somehow never got around to it.

Simply stated, my Six Natural Laws of Weight Gain are as follows:

1. Always eat when food is around
2. Always go for the gravy
3. Always eat as fast as possible
4. Always eat as much as possible
5. Don’t move if you don’t have to
6. When fuel runs short, turn down the furnace

If anyone is thinking, “hey, that’s me”, you’re probably not alone (in fact it’s me too!).

If you take a minute to think about it, you’ll probably recognize just how deeply these Natural Laws are engrained in our biology and culture and may realize how we’ve actually designed much of our environment to accommodate these laws.

Suddenly terms like “mindless eating”, “fast”food restaurants, “all-you-can-eat” buffets, “poutine”, “super-size it” and “couch potato” take on a whole new meaning.

While through the millennia of evolution these Natural Laws guaranteed the survival of our species, in our current obesogenic environment, they also pretty much guarantee weight gain.

As I have often pointed out in my talks: “In today’s obesogenic environment, people have to develop “abnormal” behaviors to avoid gaining weight”.

Doing things that came “naturally” to most of us is a surefire recipe for weight gain - in today’s enviroment, fighting obesity literally means going against our “nature”! No wonder it is so hard to do.

OK, I realize that by now some of you are screaming that this must be wrong, that I am grossly oversimplifying the complex psychosociobiology of obesity, and that I am just providing obese people with an easy “excuse” to blame it all on nature.

Of course I realize that in reality things are way more complex and that there are many paths that lead to obesity ranging from childhood molestation to antipsychotics or from genetic defects to endocrine abnormalities (the list of possible causes if far longer than you may think!).

Nevertheless, I do believe that perhaps with the exception of such “special causes” the Natural Laws do provide a reasonable and useful framework for thinking about the root causes of the current obesity epidemic.

So in the next couple of weeks, I will be occasionally revisiting this theme and hope to explore some of these laws and how they apply to our current dilemma.

Perhaps the title of my book should be: “The Six Natural Laws of Weight Gain and How to Break Them“!

I wish someday to actually find time to write it - I could probably have a lot of fun with this.

AMS