Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Daily energy expenditure through the human life course

research.brighton.ac.uk

Post reply on HN
Print view View original

91–100 of 256 posts

Re: Daily energy expenditure through the human life course

#91

Post by trefoiled »

kenjackson wrote: post #77
trefoiled wrote: post #74

Earlier quoted context omitted.

There's good evidence that metabolic rate does vary, but not significantly. https://examine.com/articles/does-metabolism-vary-between-tw...

The article states the difference is small, but also notes “ The majority of the population exists in a range of 200-300kcal from each other”. All things being even 200kcal difference per day is about 20lbs per year attributed purely to metabolic difference. Now you can say to just eat 200kcal less per day, but those little differences on a daily basis add up.

totally valid point. I would expect most people to be surprised that the variance is typically smaller than a spoonful of peanut butter, but the nature of gaining or losing weight is such that even a spoonful of peanut butter over years could be the difference between many pounds of body mass.

Re: Daily energy expenditure through the human life course

#92

Post by paulpauper »

civilitty wrote: post #90
logicchains wrote: post #70

Earlier quoted context omitted.

Muscle tissue burns 7-10 calories per pound per day. This means someone who gains 100 pounds of muscle (e.g. from 150 lbs untrained to a 250 lbs bodybuilder) would increase their metabolism by 700-1000 calories, almost a 50% increase in the average daily male calorie requirements of around 2000 calories.

Putting on 100 lbs of muscle is impossible without steroids for 99% of people even with 10-15 years of constant training. Estimates vary but 50 lbs of lean muscle mass is generally considered the natural maximum for men.

even with steroids virtually impossible. the heaviest pro bodybuilders ever peak at around 270-290 lbs

Re: Daily energy expenditure through the human life course

#93

Post by civilitty »

paulpauper wrote: post #87
reactordev wrote: post #50

Earlier quoted context omitted.

Multiply that by 15-20 years and you’re looking at a solid extra 200lbs you have. Naturally every 40 or so makes you look in the mirror, make some minor changes that last a year or maybe a bit more and it’s back to getting out from under the gelatin we’re packing onto ourselves. In order to really, truly, get a handle on your weight - you need to increase muscle mass, operate at a slight caloric deficit, eliminate ex…

Then why do so many people go to the gym, do 10k steps/day, intervals, etc. yet do not lose weight? Americans are arguably more active and health conscious than ever before as evidenced by the huge popularity of fitness content on YouTube, record number of gym memberships and attendance, the huge popularity of fitness apps, awareness of GMOs, food tracking apps, etc. yet fatter than ever too.

Because they don’t control their portions or eating habits. Take a look at the UK TV show “Secret Eaters”* which sets up secret cameras in and has investigators follow a different household every episode to estimate everything they eat down to the tablespoon of sauce. It’s an eye opening look into psychology. Lots of people think they’re eating 2K kcal or less but are in reality consuming 3-5K per day.

* full episodes on Youtube

Re: Daily energy expenditure through the human life course

#94

Post by hombre_fatal »

m3kw9 wrote: post #52
logicchains wrote: post #34

Muscle burns more energy than fat. As people age, their muscle mass declines without sufficient exercise, so we'd naturally expect the average person's metabolism to decline via this even if "metabolism per kg muscle" didn't change.

A lot of skinny people have high metabolism, how do you explain that?

Show me their Cronometer.com food/calorie diary and we'll see if the proposition even holds. Until then I'm not even willing to grant it's a thing.

In every case I guarantee they eat a normal amount of calories but feel like they eat a lot because they eat slightly more calories than normal in a single meal.

Like me eating two entrees at dinner at 16 and wowing everyone even though I skipped breakfast before school to play Runescape and had a tiny school lunch.

Re: Daily energy expenditure through the human life course

#95

Post by blipvert »

logicchains wrote: post #70
paulpauper wrote: post #43

Earlier quoted context omitted.

muscle burns very little calories, and even pro bodybuilders who have lots of muscle quickly put on fat off-season when not dieting. I don't think this explains it.

Muscle tissue burns 7-10 calories per pound per day. This means someone who gains 100 pounds of muscle (e.g. from 150 lbs untrained to a 250 lbs bodybuilder) would increase their metabolism by 700-1000 calories, almost a 50% increase in the average daily male calorie requirements of around 2000 calories.

That is an insane amount of training - big lifestyle changes!

I increased my calorific needs by 1000 a day by doing a 10K run (1hr) before breakfast.

Still a 160lb weakling :)

Re: Daily energy expenditure through the human life course

#96

Post by brigadier132 »

medler wrote: post #85
m3kw9 wrote: post #52

Earlier quoted context omitted.

A lot of skinny people have high metabolism, how do you explain that?

Over my life I’ve been close to a small handful of perpetually skinny people who thought they had high metabolisms. In every case, when I watched them closely, I realized they barely ate anything. My ex-gf was one of these people and would routinely tell people about how she could eat anything and not gain weight. But when I would go on a severely calorie-restricted diet I was still eating more than she did on a norm…

> In every case, when I watched them closely, I realized they barely ate anything

I know people (mainly Asian guys that are trying to build muscle) that seriously struggle to eat at a calorie surplus. So maybe it's not "metabolism" (which there are significant differences between humans) but also differing levels of hunger.

Re: Daily energy expenditure through the human life course

#97

Post by [deleted] »

logicchains wrote: post #70
paulpauper wrote: post #43

Earlier quoted context omitted.

muscle burns very little calories, and even pro bodybuilders who have lots of muscle quickly put on fat off-season when not dieting. I don't think this explains it.

Muscle tissue burns 7-10 calories per pound per day. This means someone who gains 100 pounds of muscle (e.g. from 150 lbs untrained to a 250 lbs bodybuilder) would increase their metabolism by 700-1000 calories, almost a 50% increase in the average daily male calorie requirements of around 2000 calories.

[deleted]

Re: Daily energy expenditure through the human life course

#98

Post by hombre_fatal »

dijit wrote: post #31
strangesmells02 wrote: post #27

Anecdotally: I havent changed diet one bit, actually I eat way healthier than when I was younger. And still weigh much more than when younger.

I think thats basically true for most people, hence the belief that metabolism slows with age. Proving that its not metabolism would imply that our weight gain in later life is a combination of other factors. I would bet good money on the increase in sedentary leisure activities, the reliance on motorised vehicles and a lack of energy to be active. I would bet on those long before anything as nebulous as diet or inta…

I can think of two major, extra lifestyle factors that increase calories in adulthood that we overlook in favor of more appealing explanations like "metabolism tho":

1. We eat out more as adults. Our skinny kid/teen selves didn't even have the money/vehicle/norm to eat out much less do it daily like we can as adults. This also includes eating out during our lunch break. Every time we eat out that's an easy 1000+ calories.

2. When you live with a partner, every time they ask "wanna eat something?" and you say "yes", that's a moment you wouldn't have eaten had you been a bachelor. We'll even say yes when we aren't hungry.

It's funny how much we want to believe in factors out of our control.

Re: Daily energy expenditure through the human life course

#99

Post by brigadier132 »

logicchains wrote: post #70
paulpauper wrote: post #43

Earlier quoted context omitted.

muscle burns very little calories, and even pro bodybuilders who have lots of muscle quickly put on fat off-season when not dieting. I don't think this explains it.

Muscle tissue burns 7-10 calories per pound per day. This means someone who gains 100 pounds of muscle (e.g. from 150 lbs untrained to a 250 lbs bodybuilder) would increase their metabolism by 700-1000 calories, almost a 50% increase in the average daily male calorie requirements of around 2000 calories.

Someone in their first year of consistent serious training can realistically put on 15 pounds of muscle. The year after that it drops to 5 pounds.

Re: Daily energy expenditure through the human life course

#100

Post by sapiogram »

logicchains wrote: post #70
paulpauper wrote: post #43

Earlier quoted context omitted.

muscle burns very little calories, and even pro bodybuilders who have lots of muscle quickly put on fat off-season when not dieting. I don't think this explains it.

Muscle tissue burns 7-10 calories per pound per day. This means someone who gains 100 pounds of muscle (e.g. from 150 lbs untrained to a 250 lbs bodybuilder) would increase their metabolism by 700-1000 calories, almost a 50% increase in the average daily male calorie requirements of around 2000 calories.

Do you have a source? I would expect the first pounds of muscle to affect metabolism more than the 100th pound, but that's my immediate intuituion.
Post reply on HN