I was researching diet, weight loss, and obesity the other day online and I was surprised to learn that the Center for Disease Control has a unisex standard for “overweight” as well as for “obese.”
This strikes me as ridiculous. Everyone knows that a fit man is significantly heavier than a fit woman of the same height. Because men are naturally more muscular. Putting common sense aside, just look at life insurance actuarial tables. The height and weight charts are shifted to heavier ranges for men. Of course, insurance companies are in business to make money. If they have concluded that a healthy weight range for men is higher than a healthy range for women, to me it’s very credible.
Am I missing something important here? Does anyone wish to defend these standards?
And why would the government define things this way? Is it political correctness run amok? Are The Powers That Be unwilling to accept that obesity is a bigger problem among women than men?
BMI is a simple measure - which is what is used as the cutoff for obese and overweight - and virtually everyone who is considered obese from the standard would be considered fat.
Plenty of people pick on BMI as a standard - and yes some athletes would be considered overweight, but let’s face it - the US is not a nation of athletes.
Studies have shown relatively similar ranges for attractiveness based off BMI for men and women.
It has nothing to do with political correctness. Different studies are free to use whatever cut offs they want for women and men - and often do.
Sometimes it looks like it doesn’t make much of a difference:
But I’m talking about the US government standards.
Actually this cite contains a great example of my point. According to the study, a man who is “overweight” has about one and a half times the risk of diabetes compared to a man who is “normal weight”
At the same time a woman who is “overweight” has about double the risk of diabetes compared to a woman who is “normal weight”
Why is being overweight dramatically more hazardous for women than for men?
The answer (I believe) is that it isn’t. It’s just that “overweight” is defined more strictly for men. A man with BMI 26 has much less of a weight problem than a woman with a BMI of 26.
I used the diabetes as an example of where there is a difference, for many things - like the last link - there isn’t one. If you look at overall mortality - it is actually higher for men (white) of the same BMI http://www.nejm.org/doi/full/10.1056/NEJMoa1000367
I get your point - and think it has merit, but for many diseases the risk profile is similar. In fact - other than diabetes - most diseases don’t start having a significant effect until after 25-30.
Actually, the first link you provided was under your statement that “Sometimes it looks like it doesn’t make much of a difference”
Thank you, I guess. Assuming that “overweight” and “obese” should be defined in terms of additional serious health risk, the question is whether the life insurance companies have it right or not. I am inclined to think they have it right, i.e. that weight ranges should be shifted up for men.
Well apparently body fat percentage is difficult to measure. But even if they went by body fat percentage, different standards would be appropriate for men and women. A fit woman has significantly more body fat than a fit man.
I haven’t seen studies, but I would guess that it does to some extent. I imagine it’s difficult to measure because muscle mass is probably correlated with other factors which have their own effects on health and longevity.
The BMI is a means of describing statistical normal that has been adapted for helping to determine what is health outcomes “normal.”
The exact cut-offs used were a bit arbitrary and chosen to make it easy to implement clinically. The first crack at it was to use the 85%ile of the then normal distribution, 27.8 for men and 27.3 for women, as being “at risk” for obesity. That was then simplified to a uniform 25 as overweight and 30 as obese for ease of use and only that. It is taken too seriously and rigidly by most, including those in healthcare. But in reality the male and normal percentile distributions did not and do not differ much. The man at 50%ile BMI has less fat and more muscle than the woman at 50%ile but they are at nearly the same BMI number.
Yes, other measures may be more useful than BMI - body fat percentage and where that fat is - but BMI is still a fairly useful screen. (And more muscle mass lowers health risks in general, improves insulin sensitivity, etc.)
No it wouldn’t. That said the difference between the numbers (27.3 and 27.8) is insignificant at the 85%ile (and other percentiles) and of no apparent prognostic significance. (For both it seems the lowest health risks are correlated with the 24 to 26ish range.) It is more a tribute to how little the powers that be thought of practicing clinicians that they felt they needed to round 27 and change to 25 (and 30 for obese) or else it would too complicated for them to use.
Choosing the borderlines by percentile is silly. It presumes that men and women are equally prone to obesity. Clearly women are more prone to being overweight and obese than men. Even by the current ridiculous unisex standard, more women than men are obese.
The borderlines should be drawn by looking at excess risk of serious health problems.
Excess risk correlates just as well (and as poorly) with BMI in both genders. Measures of central obesity correlate better in each as well. A woman and a man are not equally healthy at the overall percent body fat.
Are you saying that the insurance companies are wrong?
I mean, if you look at actuarial tables, the BMI border for men between the most preferred risk category and the next category is significantly higher than for women.
And of course insurance companies are, at least in theory, trying to assess excess risk.
Are you saying that they are wrong to make the BMI limit higher for men than for women?
That may be so, but so what? All that means is if one were to measure obesity in terms of body fat, the thresholds should be different for men and women. Which I agree with.
Are you talking about the tables that Break into small, medium, and large frame? If so - this is just one method for them to Break stuff up. Women have higher life expectancy - so it wouldn’t be odd for the tables to be adjusted somewhat. It doesn’t necessarily mean that the overweight category for men is paying the same ratio that the overweight category to women is.
The chart I found was about a 7 pound difference at ~160 lbs 5’10.
I don’t think that matters so much. Because the question is where you draw the line between people in the healthiest weight range the next healthiest weight range.
I agree, but still, the only reasonable way to interpret the actuarial tables is that the insurance companies believe the healthiest weight range for men is a bit higher than the healthiest weight range for women.
That’s only true for diabetes and is likely due to gender differences; by contrast, a man’s risk of cardiovascular disease increases faster with BMI. In fact, according to this study, men have a higher relative mortality risk at BMIs above 28, especially at the highest BMIs where relative mortality between men and women nearly doubles (it does note that the optimum BMI for men is slightly higher, 23.5-24.9 vs. 22.0 -23.4 for women; both of these ranges are also on the higher side of “normal”, 18.5-24.9).
Let’s cut to the chase: Do you think the insurance companies have it wrong when they have a higher weight cutoff for men to be in the most preferred risk category?
I cannot speak to what insurance tables, old or recent, are based off of; I can speak to what the medical literature actually has found. Based on the scientific literature what you seem to infer from whatever insurance tables you are looking at, is in fact wrong. Perhaps those tables were based off of the best available once upon a time, perhaps not, but not on what is currently known.
From a pooled analysis of prospective studies which included 1.46 million adults (this analysis White non-Hispanic), the mortality curves by BMI in both male and female total and non-smoker only groups were very similar, especially for non-smokers. So much so that they pooled the results for other potions of the analysis.
As monstro references, the same exact mortality implications may not hold for Blacks. (And note, no statistically significant difference between male and female mortality by BMI there either.) That information is still forthcoming and somewhat contradictory and controversial but there may be a gender gap there - with “overweight” by BMI (25 to 25.9) being a mortality risk for Black males more than Black females, and “obese” (over 30) for both.
As to the importance of where fat is stored and your inability to understand why that matters … I don’t know how to explain it much better. The same BMI, the same body fat percentage, has much different health implications depending on where the fat is.