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People with low BMI aren't more active, they are just less hungry, 'run hotter'

sciencedaily.com

181–190 of 350 posts

Re: People with low BMI aren't more active, they are just less hungry, 'run hotter'

#181

The article says the low BMI people ate "12% less food" (presumably that's measured in calories), though it may not be fully true that they're "less hungry". There's a very common tendency to assume that the satiety response is based on how many calories you eat, but perhaps unless you're actually starving, it mostly isn't! Primarily, you feel sated when your stomach is or has recently been full of food, but that's b…

(cf. laproscopic bands and gastric bypass being incredibly effective at causing morbidly obese people to lose weight -- they're literally just making the stomach effectively smaller). They are not that effective. the weight loss is often not enough or the weight returns. Gastric bypass, which is a major operation, will seldom make a very obese person thin and the weight tends to slowly return.

It's all relative, innit? Compared to "telling people to diet and exercise", which is an almost perfectly ineffective intervention (as usually practiced at least), getting morbidly obese people to become "merely overweight" is huge and results in considerable improvements to life expectancy and morbidity.

As summarized by Wikipedia, "median life-expectancy was 9.3 years longer for obese adults with diabetes who received bariatric surgery as compared to routine (non-surgical) care, whereas the life expectancy gain was 5.1 years longer for obese adults without diabetes", citing this meta-analysis: https://pubmed.ncbi.nlm.nih.gov/33965067/

Re: People with low BMI aren't more active, they are just less hungry, 'run hotter'

#182
post #77

Hunger is mediated by a bunch of hormones and you can test for some of those, but there is no test for the feeling of hunger. As a comparison, it is famously very hard for doctors to understand pain; it is also difficult for patients to communicate about pain. The feeling of hunger is not comparable between people. Hunger is driven by multiple sensations (blood sugar, stomach stretch, hormone levels) and by cognitive…

I lost weight during the pandemic by just trying to make sure I was hungry by the next meal time.

By that I mean, I would eat breakfast and then see how hungry I was at lunchtime. If I wasn’t very hungry for lunch, then I would still eat lunch, but I tried eating less at breakfast the next day. Same with lunch-to-dinner.

Over time my meal portion sizes came down, but I was not looking directly at that, I was just paying attention to the feeling of hunger.

What I realized was that I would eat a big breakfast and then a big lunch just because it was lunchtime. So I was overeating; basically taking in more calories than my body needed. It was a combination of habit and not thinking about what I was feeling. I realized that I should feel pretty hungry before a meal, but I wasn’t letting that happen.

I totally agree with you that hunger is subjective and hard to measure outside of our own perception. I’m not sure I could have or would have done this based on someone else’s coaching. It’s hard to calibrate my personal feeling of “hungry enough” based on what another person says. And it takes motivation, which has to come from within.

Re: People with low BMI aren't more active, they are just less hungry, 'run hotter'

#184
post #77

Hunger is mediated by a bunch of hormones and you can test for some of those, but there is no test for the feeling of hunger. As a comparison, it is famously very hard for doctors to understand pain; it is also difficult for patients to communicate about pain. The feeling of hunger is not comparable between people. Hunger is driven by multiple sensations (blood sugar, stomach stretch, hormone levels) and by cognitive…

People in developed countries have become too accustomed to comfort. We need be accept a certain level of discomfort and pain. Embrace the suck.

And most people with high BMIs didn't get that way eating steak and baked potatoes. In fact, if you live entirely on that diet it's quite difficult to get fat.

Re: People with low BMI aren't more active, they are just less hungry, 'run hotter'

#185

Earlier quoted context omitted.

> I've known very active cyclists that couldn't lose weight despite riding hundred mile rides weekly. Isn’t this against the laws of physics? If you’re burning a ton of energy and not eating excessively, where are their bodies getting mass from to maintain weight?

Doing tons of endurance cardio gives you massive carb cravings and catabolizes muscle mass, slowing your metabolism. Especially when none of it is max effort. To keep your body fat percentage low and metabolism up you really need to combine endurance cardio with high intensity cardio and strength training. This is why things like Crossfit and HIIT are so popular.

Sorry I just don't agree with this. I run 50 miles a week and mix in some cycling too, and I actively have to make an effort to eat enough to maintain weight. Endurance cardio doesn't trigger hunger or cravings for me unless it's a long (90 mins plus) effort.

Re: People with low BMI aren't more active, they are just less hungry, 'run hotter'

#186

I eat all the time. I run hot. I also fat. I also think BMI is not a good measurement, not just because it says I'm morbidly obese, but also because it skews in favor of those with smaller frames for their height.

BMI seems to be one of those things that everyone in the relevant field knows is pretty damn bad, but no consensus has formed around anything better so they keep using it anyway.

(I'm sure there are parallels to things in the software world - SQL comes quickly to mind - but that's a bit OT so I'll resist the temptation to explore that idea further.)

Re: People with low BMI aren't more active, they are just less hungry, 'run hotter'

#187

The article says the low BMI people ate "12% less food" (presumably that's measured in calories), though it may not be fully true that they're "less hungry". There's a very common tendency to assume that the satiety response is based on how many calories you eat, but perhaps unless you're actually starving, it mostly isn't! Primarily, you feel sated when your stomach is or has recently been full of food, but that's b…

(cf. laproscopic bands and gastric bypass being incredibly effective at causing morbidly obese people to lose weight -- they're literally just making the stomach effectively smaller). They are not that effective. the weight loss is often not enough or the weight returns. Gastric bypass, which is a major operation, will seldom make a very obese person thin and the weight tends to slowly return.

My brother underwent this surgery, and not only did the weight come back, he developed a serious drinking problem (he's in recovery now). Apparently, this a known side effect. All it really did was make his life much harder in the long run. Hunger is more that the physical feeling of fullness.

source: https://www.health.harvard.edu/blog/alcohol-abuse-linked-to-...

Re: People with low BMI aren't more active, they are just less hungry, 'run hotter'

#188

"people with low BMI" seems like it refers to a large group of healthy people, but it actually refers to folks who are underweight. In China, that's like 1 in 10 people. In the USA it's closer to 1 in 50. I wonder what kind of genetics and behavior you have to have to be underweight in the USA.

Are 1 in 50 people in the US (ab)users of uppers? That could account for some of it.

Also anorexia and other Medical comorbidities. A Many cancer patients have trouble keeping weight too

Re: People with low BMI aren't more active, they are just less hungry, 'run hotter'

#189
I vaguely remembered that the doubly-labeled water method was pretty neat, but I looked it up and it is as neat as I remember:

https://en.wikipedia.org/wiki/Doubly_labeled_water#Mechanism...

It's like plugging yourself into a power meter, except for cellular respiration

Re: People with low BMI aren't more active, they are just less hungry, 'run hotter'

#190

Earlier quoted context omitted.

Overeating is the root of it. It's popular to deny this and come up with other excuses; normally when I'm with somebody making those excuses for themselves I don't dispute any of it (because it's not worth the social capital I'd expend in doing so.) But what really ticks me off is when somebody offers those lame excuses up for my obesity. I'm not big boned, there's not something wrong with my metabolism, I don't have…

It’s good you are honest with yourself about it. Unfortunately I don’t know what the solution is, if you find one let me know so I can pass on to my friends. I binge eat too; it’s just doesn’t take that much to get me full. If I had to eat more to feel full, I’d be fat too. Very few people have the willpower to stop eating while still hungry and with food in front of them.

Similar to substance abuse problems, people with overeating issues often have to "hit rock bottom" in order to gain sufficient motivation and discipline to sustain a permanent behavior change. This often takes the form of a serious medical crisis, or losing a valued personal relationship.
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