Current Events > PSA: Age has an almost neglible effect on metabolism

(+) Yeah! (+)

BMR(men) = 10*weight in kg + 6.25*height in cm - 5*age in years + 5

tl;dr BMR decreases 5 calories every year. Five, fucking, calories.

Here's the rub though: Take Average Joe America, he's an average 5'10", 190lbs. Super average guy. He has a TDEE of roughly 1.55x BMR (moderately active), he eats 2910 calories a day which is perfectly equal to his TDEE at age 20.

His calories in = TDEE which means his weight will not change at age 20. However his BMR decreases by 50 calories a day in 10 years at age 30. Now he's eating a caloric surplus of roughly 50*1.55 = ~80 calories a day. If you rearrange the BMR to calculate his new breakeven weight based on his caloric surplus, you would find that his new weight at age 30 would be 200lbs. This relationship between age and natural weight is linear.

20 years old = 190 lbs
30 years old = 200 lbs
40 years old = 210 lbs
50 years old = 220 lbs

So you're probably saying "Clear, you spiteful piece of garbage, what are you trying to tell us?" It's simple: BMR barely decreases over time, but if you don't adjust your caloric intake to accommodate for this tiny decrease, your weight wil gradually creep up by about one pound every year. For every decade of your life you need to decrease about 70-80 calories consumed every day, which is approximately one double stuffed oreo (alternatively you can burn that amount by walking one mile).

FAQs:

Q: But BMR varies wildly between people! I'm special! Muh thyroid!

A: No, unless you have a legitimate medically diagnosed condition you are NOT special. BMR has a standard deviation of 140 calories, we all are pretty much in the same boat, adjust your intake according to your body's needs.

Q: But your body loses muscle when you get older, and less muscle means your metabolism slows down!

This is mostly a myth, it is true that body composition changes with age, but the extent is unclear (i.e. a weight lifting 50 year old would have more testosterone and muscle mass than an untrained 20 year old). Regardless, the effect of muscle mass on BMR is negligible. Fat free mass has a much stronger relationship than muscle mass, and even then that variation of BMR attributable to FFM is small. The amount of muscle on your body has almost zero impact on your metabolism. Total body weight is sufficient for calculating BMR

Q: This is all bullshit, it's not that simple, meal timing/keto/macro ratios/supplements/caffeine play too big of a role to dismiss, you're generalizing.

True, this is overly simplistic and my weight calculations based on age may not be exact, but the principle behind it is valid. Calories in, calories out, track everything you eat, pay attention to your body, be healthy.

Q: Dude why are you obsessed with fat people?

There is a massive correlation between overall health and your waist to height ratio, 70% of Americans are overweight and 35% are obese. People should care more about their health and all they need to do is eat less calories and stick to their plans.

Q: You're a fucking asshole

A: I know

um, QED?
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I'll bump this forever

Bump

Meh. My body could use extra pounds.
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Why have I gained 3 pounds over the weekend?!?
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clearaflagrantj posted...

tl;dr BMR decreases 5 calories every year. Five, fucking, calories.

Which means my TDEE decreased by 7. SEVEN!!!

In 10 years, that's one less apple a day! And then I'll need to see a doctor!

krazychao5 posted...

Why have I gained 3 pounds over the weekend?!?

Salt intake, carb intake, water intake, poop. It wasn't 3 pounds of either fat or muscle.
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krazychao5 posted...

Why have I gained 3 pounds over the weekend?!?

Philsov is exactly right. The scale is highly misleading in the short term, it doesn't paint the whole picture. Weight variance can be anywhere from +4% to -2% of your "true" weight.

Also explains why when you first diet you see amazing results. You eat less, which means less salt and carb intake, which means your body holds less water weight, so the scale says you lost 5lbs. But you didn't actually lose any significant weight and when your body normalizes your new salt/carb intake you gain all that water weight back and your weight loss "slows" to an actual rate.

That's why with long term diet it's best to track your weight over weeks and for the most part ignore your daily weights. You need to eat at a deficit, track the moving average of your weight, and aim for 0.5-2.0lbs lost a week (based on your goals).

Age has an almost negligible affect on metabolism

Nothing in this topic has proven this to be true.
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So how do I find my true weight if my daily weight ins't real?

~.~

MikeGesicki posted...

Age has an almost negligible affect on metabolism

Nothing in this topic has proven this to be true.

Age has an effect, but it is less than what is construed to be. People talk about how it affected them compare their current life, usually in the 30's, to when their metabolism was faster, in their 20's or teens. This is a long time, and of course, metabolism slows down during that decade-plus time. Year-over-year average shows that it is a small effect of metabolism slowing.
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MikeGesicki posted...

Age has an almost negligible affect on metabolism

Nothing in this topic has proven this to be true.

I'm on mobile so right now I'm too lazy to cite my sources. I can easily cite the BMR calc and the standard deviation. The math is based on those observed scientific facts.

krazychao5 posted...

So how do I find my true weight if my daily weight ins't real?

~.~

Weigh yourself every morning and calculate the 3-7 day moving average.

Accurate topic. Always been a huge pet peeve of mine when people say OH I WISH I COULD EAT LIKE YOU. IT'LL CATCH UP TO YOU SOMEDAY.

I've been hearing this shit for the past 15 years and it never has. Either give me credit for living an active lifestyle and exercising, or admit you're a lazy fuck that eats too much for your level of fitness. Stop blaming age.
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ForestLogic posted...

Accurate topic. Always been a huge pet peeve of mine when people say OH I WISH I COULD EAT LIKE YOU. IT'LL CATCH UP TO YOU SOMEDAY.

I've been hearing this shit for the past 15 years and it never has. Either give me credit for living an active lifestyle and exercising, or admit you're a lazy fuck that eats too much for your level of fitness. Stop blaming age.

Don't forget women that act like men can eat anything they want and not gain weight.

clearaflagrantj posted...

BMR(men) = 10*weight in kg + 6.25*height in cm - 5*age in years + 5

Lmao, love it when people write out and interpret the results of a regression as if it were a law.
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clearaflagrantj posted...

MikeGesicki posted...

Age has an almost negligible affect on metabolism

Nothing in this topic has proven this to be true.

I'm too lazy to cite my sources..

Well then you cant expect anyone to take you seriously.
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tbh I never evr weighted myself when I started working out, I was a skinny fat dude that went from having a big gut to being skinny as fuck and when I noticed, I started actually weigth lifting and eating more because just losing weight was not gonna make me look good, there cme a point where my body just got really fucking good and I kept at it.

Fuck tracking calories or weighting yourself, if you actually keep at it for years it's gonna work, if you won;t commit then you deserve to be a fat slob.
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I dunno man. I eat less and eat way better in my 30s than my 20s and I gained weight. Physical activity is more or less the same. Also for some reason I cant handle caffeine anymore either.
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COVxy posted...

clearaflagrantj posted...

BMR(men) = 10*weight in kg + 6.25*height in cm - 5*age in years + 5

Lmao, love it when people write out and interpret the results of a regression as if it were a law.

Lmao, love it when people have nothing to add but want to mentally jerk off to try to impress others

clearaflagrantj posted...

COVxy posted...

clearaflagrantj posted...

BMR(men) = 10*weight in kg + 6.25*height in cm - 5*age in years + 5

Lmao, love it when people write out and interpret the results of a regression as if it were a law.

Lmao, love it when people have nothing to add but want to mentally jerk off to try to impress others

The entire crux of your argument here is doing algebra on an equation as if it were some fundamental law, when in reality it is the result of a regression with a drastic amount of error. Do you not want people to comment on your argument?

Or just not when they aren't just agreeing because it fits their prior?

Also, any estimation of an effect size across age computed across subjects (rather than longitudinal) is pretty much useless. So without that information, it's impossible to say whether or not the parameter itself has any real meaning to begin with, never mind the algebra bullocks.
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CapnMuffin posted...

I dunno man. I eat less and eat way better in my 30s than my 20s and I gained weight. Physical activity is more or less the same. Also for some reason I cant handle caffeine anymore either.

Are you taking any medications though? Some of those can straight up brick your metabolism, SSRIs being a common example that a lot of people are on.

Definitely agree with everything else in this topic though. I'm turning 32 this year and I'm still in the second best shape of my life, right next to 19-20 year old me. I'm sure I'll slow down a bit if I become less capable of maintaining a high level of fitness due to injury or just being too old, but then I would probably just eat less to compensate.
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I walk 4 miles a day and I'm still fat

but my heart is healthy
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