November 7, 2007

"Overweight" is Healthiest Weight

This is not actually news, as there was a good study published some years ago that found the very same thing to be true, but a new study presented at this years American Heart Association meeting confirms the finding, and has led to some headlines on the topic.

The basic message here is that you are most likely to live a long and healthy life if your BMI is between 25 and 30, which for a 5' 4" woman means having a weight of 150-174 lbs and for a 5' 10" man is 175 - 208 lbs.

Here's a report on the finding from the New York Times.
Causes of Death are Linked to a Person's Weight

Here are some earlier large population-based studies that have found similar results:

From JAMA in 2005 based on NHANES III data

Here is a further review of the NHANES data that points out that over age 70, overweight AND obesity are more healthy than normal or underweight. Be sure to scroll down to Table 4.

Supplemental Analyses for Estimates of Excess Deaths Associated with Underweight, Overweight, and Obesity in the U.S. Population
by Katherine M. Flegal, Ph.D.


The current data does NOT break health down by decade, which is a shame, because the strongest signal in the NHANES study points to weight becoming increasingly healthful as we go through middle age. By not breaking mortality figures out by age, we may miss this vital point.

This data flies in the face of our society's obsession with thinness and its tendency to equate near-anorexia with moral superiority and overweight to sinfulness. However, as anyone who is over 50 knows, at middle age the body ramps up its weight gaining mechanisms to the point where it is almost impossible NOT to gain weight. Now this research suggests that there is a reason for it, and it is not that we suddenly become lazy, greedy slobs.

As we age, the metabolism slows down at a predictable rate. The result of this slowing is that at 59, I can now gain weight eating the same diet that I would have lost weight on at age 40. A diet, by the way that has the same number of calories used to induce starvation in men who averaged a weight only 10 lbs more what I now weigh during Ancel Keye's famous WWII Starvation Experiment.

This is not because I am less physically active than I was at 40, which is the usual excuse given for middle age weight gain. No, my body has clearly decided that I need an extra 20 lbs and the more I fight it the harder it fights back.

So what a sudden revelation it is to realize that maybe my body is doing this because it is trying to keep me alive!

There is a predictable backlash to this data from people who know it has to be wrong. But as the analysis of the NHANES research linked above shows, their belief that overweight is unhealthy may derive from studies that cherry-picked the data in such a way as to achieve the result that the researchers already believed to be true. Taubes' work has made it very easy to see how common this is in so-called scientific studies.

And it's also worth remembering many of the claims of excess mortality linked to weight, like Julie Gerberding of the CDC's famous discredited estimate of mortality due to overweight, were pulled from thin air.

Does this mean you should rush out and gain weight? Of course not. Does it mean that carrying an extra 100 lbs is good for you? Again, of course not. The health benefits of weight drop off significantly at a BMI of 35--204 lbs for a 5' 4" woman and 244 for a 5' 10" man.

In addition, the BMI as an index to health has to be taken with a grain of salt, because it completely the two Bs: boobs and brawn. I'm carrying 6 lbs of boob, which do not go away even if I weigh 108 (I've tried it.) That raises my BMI by 1.1. Does this mean I'm much less healthy than a completely flat chested woman of my size? I doubt it.

In a similar manner, when my son was playing on his college football team, he had a BMI well into the "obese" range, based on his height and weight, though he was measured as having a body fat percentage of 17% which is normal for a male. This discrepancy was because he was carrying an enormous muscle mass which the BMI calculations treat as if they were body fat.

One of the things doctors always tell people with diabetes is that if they could lose as little as ten pounds, they could lose the diabetes. Hundreds if not thousands of you reading this blog have probably tried this and found it to be nonsense. Some of us, like, say, me, have lost over 15% of our body weight and found it to have zero impact on our blood sugars.

Well, heave a sigh of relief. Your weight is not going to kill you. Then take another deep breath because no matter WHAT you weigh, your blood sugars might: the connection between blood sugars rising over 140 mg/dl after each meal and heart attack is very well documented with more research confirming it every year.

So concentrate on getting those blood sugars down. Get your A1c as close to 5% as you can, and once you do look forward to having long debates about "healthy eating" with your grandkids and great grandkids!

6 comments:

Helen Howes said...

Oh, bugger. I've just weighed myself and my BMI is under 25 for the first time in 17 years... Mind you, I do feel much better for the weight loss and my IR is way down...

Seriously, though, I was told many years ago that any female who starts thin (I was very thin as a youth) should be able to carry an extra stone (14 lbs) for each decade...

Helen Howes

Jenny said...

Helen,

Not a problem. The real message here is not to obsess about the kind of weight gain that does not respond to prudent eating and normal exercise.

Many of us will see our weight drop drastically after we normalize our blood sugars, often without conscious dieting.

But most of us will also find that our weight stabilizes 10-20 pounds higher than the goals we've been told were healthy.

This research suggests that that 10-20 pounds over the nutritionist-suggested weight is just right.

nonegiven said...

Well, I feel better. I have a much better chance of making it to overweight than I do getting to normal.


Do you have an opinion on this?
http://www.contactmusic.com/news.nsf/article/berry%20beating%20diabetes_1048407

Jenny said...

Nonegiven,

I have commented on Berry on TuDiabetes. If she was told she had Type 1, she was obviously misdiagnosed.

She may well have one of the genetic forms of diabetes that can look like Type 1, but respond strongly to sufonylureas. Confusing that with Type 1 is very common in thin people who develop high blood sugars in their 20s.

Rachel... said...

I feel like I have a "natural" weight pull towards 135-144. Any higher than 144 and my blood sugars go wacky, but I don't necessarily need to be at 125 ("ideal" weight) either.

(And I'm probably carrying around that much boob weight, too. *lol*)

R. Francis said...

Glad you mentioned the "just lose 10 pounds" thing. I lost 45 pounds -- a 16% or so drop in weight -- and lo and behold, still diabetic! Imagine that.

As for BMI, well, mine's 34, so I guess I'm not perfect yet. (Seriously, I'd like to see my weight down around 200, which would be a BMI of just under 30, it turns out.)

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