Similar findings are found for younger populations, not quite overweight but top “normal” BMI, 23 to 25 or even 26 (depending on the exact study) has lowest mortality rates, and under 21 to under 19 goes up somewhat dramatically.
“Overweight” is as defined by BMI values. A BMI of 28, the middle of that lowest mortality rate quintile for males, and 26, the middle of the female lowest rate quintlie, are both in the middle 25% of BMIs for 75 year old males and females respectively. So while it is “overweight” by BMI definition it is also “average” or at least “typical.”
Yes, it is a marker. It certainly could be that good health and good habits result in a more solid BMI and poor habits or temperment issues (lower activity, less social networks, more sub-clinical depression, etc.) result in low BMI. It might not be the BMI causing the outcomes but the other way around.
BMI is not a precise measure of fatness or leaness, especially in this “overweight” range. Higher BMI in this range may reflect more retained fat-free mass, with the same or even less fat mass.
That said as Athena notes, it makes some sense that there might be some advantage to having some reserves going into one’s 70s 80s and beyond. Prolonged illnesses happen. Some modest amount of fat reserves help spare fat free mass from being utilized for energy during those time periods. Greater fat free mass is both a marker of good health and required for full independent function.
One additional potential explanation for these findings showing so little downside to obesity in the elderly they discuss is that those prone to obesity related mortality may have already died before hitting this age group … hence the obese elderly are the healthy survivors. They also consider the group who become obese in old age and speculate that the complications of obesity take long enough to occur that they have little impact on someone already elderly.
In any case it is clear if all we know is whether or not an elder is lean or “overweight” we should bet on the overweight one being healthier and living longer.
Thank you for this DSeid. It was very interesting. My BMI is 27 and I am not trying to lose any more weight (It was once up to 38). My wife’s is 30, but her gynecologist did some measurement and concluded that she had high muscle mass. My friend is 24 and his wife is under 14.
Is the wife anorexic? She claims she wants to gain but cannot because of the nausea. She has certainly never suggested she wants to lose weight. If it hadn’t been her putting her husband on a diet, I wouldn’t have wondered whether she has a distorted body image. She never weighed over 100 lb in all the years I knew her, but the situation is now extreme. She is a former ballet dancer BTW, in the Canadian Ballet. I know a couple of other ex-dancers and they are both butterballs. It seems like once they stop training and dieting they go to fat. She didn’t.
I lived with a dog once who was allowed to free-feed to his heart’s content. We had a bowl of kibbles and a bowl of water set out at all times. Doggie ate as much as he wanted whenever he wanted. Typically, he ate small amounts at many times during the day.
He was a perfectly healthy (weight-wise) dog, not overweight at all. He self-regulated quite well. (Although, being epileptic, he wasn’t otherwise perfectly healthy. I would have no idea if all his meds affected his appetite. But he seemed healthy and active.)
I just noticed this: Your forced-diet friend came over to your house on his “forced diet” day. Why didn’t he take advantage of the opportunity to pig out? Sound like he’s actually bought into his wife’s dietary prescription for him.
Someone who (from the sounds of it) is a perfectly normal, healthy weight who is dieting has totally bought into his wife’s disordered thinking.
All this talk about BMI is a reminder that your BMI isn’t necessarily your best weight and health measurement, either. I think it can be part of figuring out how to be healthy, but it isn’t the whole story.
5’ 7"and 150 lbs is perfectly fine. That’s Marc Anthony with 10+ pounds added on.
The 5’ 4" under 80 lbs wife is another story. She has a serious food aversion problem.
My doctors use this method of height & weight for women, 100 lbs for 5’, plus 5 lbs for every 1 to 1 1/2 inches after the first 5 feet. 5’ 4" = 115 to 120 lbs for a medium to large frame woman. The height weight ratio for men is just a little bit higher for men.
I think your doctors are significantly low - plugging those numbers into a BMI calculator for me at 5’6", it says “Be careful! Your waist to height ratio is too low!” I’m overweight now, but when I was at my fighting weight, I was around 150, healthy and very strong.
The friend and wife may have developed a defense against acknowledging the full significance of his wife’s problem. My grandmother lost homeostasis at the end of her life. Many elderly people do. The feedback loop that told her when to eat stopped working. She never felt hungry and it felt wrong to be eating when there was no trace of hunger. (It could have been worse. The loop that tells you when you’re thirsty can go, too, and that can have devastating effects if it’s not noticed and corrected for.)
Being something of a drama queen and accustomed to overstating any illness, Grandma would talk mournfully about her lack of appitite constantly and do things like going to her regular restaurant, where the waitresses knew her, and making a big deal about not being able to get through an order of toast. (And then telling us all about how they worried over her.) My practical sister’s response when phoned was, “Grandma, there’s this stuff called Ensure. You can get it at the drug store. Drink three cans a day and then it doesn’t matter what you eat.”
Losing homeostasis is a sign of decline due to aging. Her former experience in ballet may be helping her to shrug off the weight loss. A culture of thinness may be helping her to shrug off the wieght loss. But if she wasn’t anorexic before, then this is probably either age or disease related. (Just because they haven’t found the cause doesn’t mean there isn’t one.) Both of them are probably more comfortable believing that he needs to diet than worrying about the danger that her weight loss may represent.