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

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

#151

Post by n8henrie »

There seems to be a lot of people in this thread conflating "feeling" hot with having an elevated metabolic rate, but I think these will be at best coincidentally concordant.

Anecdote vs anecdote, my wife is always cold, but she's the naturally-thin-never-exercises one, whereas I am the ever-sweaty always-hot one that exercises regularly, and I'm usually overweight.

Or, for example, patients with fever have an objectively elevated temperature by definition, and usually report chills (and ask for extra blankets).

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

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

#152

Post by Terretta »

malfist wrote: post #115
zeroonetwothree wrote: post #99

Earlier quoted context omitted.

I actually tried this and it didn’t work for me. My weight stayed the same. Maybe my body is just hopeless. Is there actual evidence that this is generally effective?

Weightloss is made in the kitchen, not the gym. It's really really hard to burn more calories than you eat. That extra donut or candy bar you had? That's an hour or so on a treadmill. The good news is that almost all diets work, find one you can stick to and stick to it. You should see results. It's not a fast process though. It didn't take a week or a month to put on that weight, it's not going to take a week or a m…

Yes, this is the conventional wisdom, and 100% also works. Put simply, "to lose weight, eat less."

Cutting out something specific without replacing it can work wonders. For instance, cut out sugar water (soda) and do not replace it with anything. You don't need to count calories, you will take in fewer of them, and you will lose weight.

> "it's really hard to burn more than you eat"

Yes, flip side is "or burn more" which, 100% agree, is incredibly difficult. As I noted, most people don't have the will to make themselves feel sick from anaerobic effort.

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

#153

Post by convexfunction »

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 based more on the mechanical stretch of the food on the walls of your stomach than anything else (cf. laparoscopic bands and gastric bypass being incredibly effective at causing morbidly obese people to lose weight -- they're literally just making the stomach effectively smaller).

There's certainly some truth to "running hotter" as well, at least in some of those subjects, but I'll bet that many of them are habitually eating a less energy-dense diet than heavier people, rather than feeling less hungry for any more innate reason. Dietary energy density has been investigated in lots of experimental and observational studies and found to do an overall very good job of predicting current BMI, long-term weight loss, and in metabolic ward experiments, ad libitum caloric intake.

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

#154

Post by drakonka »

seabrookmx wrote: post #142
drakonka wrote: post #93

I wish the "running hot" part was true for me. I feel cold so easily, to the point that I had to get myself checked out this year since my toes would go numb at the slightest chill. The hunger thing rings true, though. I often just forget to eat and end up eating one meal a day or maybe a meal and a snack. Then again, on other days I might snack through the whole day. It seems to balance out though; after a day of fr…

That sounds like Raynaud's.

I think that was one of the avenues they considered, but ultimately they didn't come up with any particular diagnosis and told me not to worry about it since they ruled out the obvious dangerous causes.

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

#155

Post by dilap »

wowokay wrote: post #100
dilap wrote: post #78

There's a really interesting study they did with pigs. They fed pigs four different diets that had the same amount of calories, but varying ratios of n3/n6 fats. The pigs with high n6/n3 ratio ended up much fatter and less muscular than the pigs eating a 1-1 ratio diet. It's a very neat demonstration that "all that matters is calories" is not true; your metabolism, and thus how you use the calories, is influenced by…

That’s very interesting. I’m curious how it could relate to humans. Not to say it can’t be 1:1, but there are mental aspects that can effect human hunger and I’d be interested in research around that. For example someone who eats a lot but falls into a depression might slow eating considerably (or eat more depending on the person) it’s not to far fetched to consider the possibility of mind state altering medication t…

Absolutely, the mental aspects of hunger are huge, as anyone who has ever had the munchies (super hungry) or taken adderall (super not hungry) can attest.

In fact, n6 fats may also promote hunger, via increasing endocannabinoid production.

Here's a study I just found in mice:

https://pubmed.ncbi.nlm.nih.gov/24081493/

Again just an animal model, but certainly suggestive...

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

#156

Post by convexfunction »

csours wrote: 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…

> losing body fat means that you must continuously make choices that decrease your comfort in some way - eating fewer highly rewarding foods, maintaining a state of hunger, increasing activity level

Not necessarily! I've successfully lost a lot of body fat (~50 pounds over the last 18 months) by deliberately changing my diet to eat more foods (that I like) that are lower in energy density than what I was eating before -- fruits and veggies, lean meats, etc. I do end up eating fewer stereotypically highly rewarding foods, but that's because I'm already full of other highly rewarding-to-me foods and don't feel like having a treat or a huge fast food meal or whatever. And I'm certainly not tolerating frequent hunger!

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

#157

Post by winrid »

donkarma wrote: post #131
winrid wrote: post #130

I'm one of these people. Always super hot after eating, especially carbs (which I now avoid). Hard to gain weight even at 28. I also almost always wake up covered in sweat and have to change cloths. So not all roses.

most people wake up sweaty

In the middle of the night? Having to change underwear and socks too? :P

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

#158

Post by BlargMcLarg »

jacamera wrote: post #141
CJefferson wrote: post #113

I think the hungry bit is often under-discussed. I lost 75kg over 3 years, then put exactly 75kg back on over the 4 years after that. While losing weight, and keeping it off (for about 6 months), I was hungry all the time, every day. I hoped that my body would eventually "get used" to the new standard, but in the end (not conciously), I gave up -- it was too mentally tiring to be hungry whenever I was awake. I'm sure…

Did you ever try fasting for an extended period of time during any of that? I've never gone more than ~48 hours but from what I've watched and read, people seem to stop feeling hungry after say four or five days. I wonder if that could maybe act as a sort of hard reset for the constant feeling of hunger you experienced.

Not a hard reset but my experience with a 72 hour fast has definitely been not feeling hungry, and the moment of eating a lot again restarted the entire thing. Feels like it is much easier to learn to eat a lot rather than eat very little.

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

#159

Post by deltaonenine »

tonyarkles wrote: post #106
Terretta wrote: post #83

Yes, and, about 8 minutes of true HIIT* at least 3 days a week for 6 weeks is proven to adjust your metabolic run level. Graph your weight. After 6 weeks of HIIT, you'll see weight really shed because you're not burning calories during exercise but 24/7, and because of that metabolic shift, the weight will continue to shed for months even if you stop HIIT. * HIIT is High Intensity Interval Training. It's a technical…

It's really quite amazing how quickly it affects aerobic endurance as well. I had a knee injury, waited 9 months for surgery, recovered, did a self-planned physio routine, and started feeling ready to get back into aerobic exercise. There was a 5km fun run in town that I figured I'd use as motivation. I did a slightly modified HIIT routine: walking warm up to the football field a few blocks away from my house, 8x fla…

This is real and scientifically validated. The first person who ran the 4 minute mile changed the game by using intervals. Prior to that everyone trained for the mile by running the mile.

Athletes who train for the mile have to have intervals as the majority of their regiment. This is by far more effective then running long distances for increasing vo2 max.

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

#160

Post by stonemetal12 »

CJefferson wrote: post #113

I think the hungry bit is often under-discussed. I lost 75kg over 3 years, then put exactly 75kg back on over the 4 years after that. While losing weight, and keeping it off (for about 6 months), I was hungry all the time, every day. I hoped that my body would eventually "get used" to the new standard, but in the end (not conciously), I gave up -- it was too mentally tiring to be hungry whenever I was awake. I'm sure…

It is my understanding is it takes a year before that reset happens.
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