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When somebody loses weight, where does the fat go?

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Re: When somebody loses weight, where does the fat go?

#51

Post by killjoywashere »

kgabis wrote: post #44
ransom1538 wrote: post #39

Earlier quoted context omitted.

"For anyone coming straight to the comments looking for an answer to the question: it turns into CO2 (and a bit of water) and you breathe it out." That is why you weigh less when you wake up in the morning (pre-bathroom -/+ yes some sweat).

Also water vapor from you breathing.

The water is the vast majority of the overnight weight loss. pCO2 of 40 mmHg is normal. Resting tidal volume is 500-600 mL, and a breathing rate of 12-14 (officially 10-20, but really, more like 12-14). I'll let someone calculate the mass of CO2 exhaled in 8 hours.

Re: When somebody loses weight, where does the fat go?

#52

Post by srcmap »

Zanta wrote: post #12
JoeAltmaier wrote: post #7

Earlier quoted context omitted.

Exercise makes more sense! Breathing hard == losing weight!

From the paper "Replacing one hour of rest with exercise that raises the metabolic rate to seven times that of resting by, for example, jogging, removes an additional 39 g of carbon from the body, raising the total by about 20% to 240 g. For comparison, a single 100 g muffin represents about 20% of an average person’s total daily energy requirement. Physical activity as a weight loss strategy is, therefore, easily fo…

I wish there is a way to allow one to enjoy eating but control how much to absorb the food.

Re: When somebody loses weight, where does the fat go?

#53

Post by adamc »

StevePerkins wrote: post #37
Zanta wrote: post #12

Earlier quoted context omitted.

From the paper "Replacing one hour of rest with exercise that raises the metabolic rate to seven times that of resting by, for example, jogging, removes an additional 39 g of carbon from the body, raising the total by about 20% to 240 g. For comparison, a single 100 g muffin represents about 20% of an average person’s total daily energy requirement. Physical activity as a weight loss strategy is, therefore, easily fo…

I can't help but groan at some of the "obvious" health and weight loss platitudes that get smugly thrown around. " Calories in, calories out! " " You can't outrun a bad diet! " " Weight is lost in the kitchen! " Sure, things ultimately boil down to intake-vs-expenditure. However, it IS more complicated than that in practice . As software developers, we complain when management makes decisions based on inadequate or p…

My experience supports this. Exercise helps far more than the mere calories expended would suggest.

Re: When somebody loses weight, where does the fat go?

#54

Post by IpV8 »

leshow wrote: post #48
adekok wrote: post #38

Earlier quoted context omitted.

2 pounds a day. That's how much CO2 you breath out, and the hard limit for weight loss. You can lose more than that, (see boxers before a weigh-in), but that's all water loss, and is temporary. And, with a strong likelihood of death.

I'd suspect the more exercise you do the more that number moves up, you'd be breathing harder. I'd hesitate to try and put a 'hard limit' on anything like this.

Also take daylight savings into account, you could get an extra hour one day a year. Thats a lot more breaths.

Re: When somebody loses weight, where does the fat go?

#55

Post by Jhsto »

Filligree wrote: post #26
k__ wrote: post #15

Earlier quoted context omitted.

200g are what would be "breathed out" in one hour without exercise? So you can only increase your "burn rate" by 20%?

A remarkable fraction of your energy consumption is spent on basic maintenance, and of the rest, far more than you'd think is spent on the brain. Your body is extremely efficient, by engineering standards, but that includes locomotion. Exercise is still a good way to drop in weight, but not simply due to burning up the fat; that could happen anyway. What seems to be happening is that the exercise improves the body's…

> The goal is to eat less because you don't feel hungry, not despite feeling hungry. Very few have the willpower to literally starve themselves.

I'm not sure if I understand this correctly, but isn't this a bad practice? I mean, I can agree with the sentiment of eating too many times per day. E.g. if you tend to eat snacks and then soon after a real meal, then you should definitely use your willpower to just skip the snacks before your upcoming meal.

But as far as I know, if you don't exercise and instead just starve yourself, the body first burns through your muscles before it gets to fat. If that's so, then some exercise is crucial to upkeep your muscles even while on a calory deficiency.

Re: When somebody loses weight, where does the fat go?

#56

Post by xhruso00 »

mikeash wrote: post #4

For anyone coming straight to the comments looking for an answer to the question: it turns into CO2 (and a bit of water) and you breathe it out. When you realize that you have to breathe out all the weight you lose, I think it gives you a bigger appreciation for how difficult weight loss can be.

Can I lose weight by breathing faster instead of excersizing?

Re: When somebody loses weight, where does the fat go?

#57

Post by adamc »

misterdata wrote: post #14
Zanta wrote: post #12

Earlier quoted context omitted.

From the paper "Replacing one hour of rest with exercise that raises the metabolic rate to seven times that of resting by, for example, jogging, removes an additional 39 g of carbon from the body, raising the total by about 20% to 240 g. For comparison, a single 100 g muffin represents about 20% of an average person’s total daily energy requirement. Physical activity as a weight loss strategy is, therefore, easily fo…

The question is whether the body spends any energy outside of that hour after exercising (e.g. by growing muscle, etc.) than it would otherwise. That would make exercise more effective when considering longer periods of time.

That's not the only way it helps. It tends to curb appetite.

Re: When somebody loses weight, where does the fat go?

#58

Post by arikrak »

mikeash wrote: post #4

For anyone coming straight to the comments looking for an answer to the question: it turns into CO2 (and a bit of water) and you breathe it out. When you realize that you have to breathe out all the weight you lose, I think it gives you a bigger appreciation for how difficult weight loss can be.

Meanwhile the reverse happens when a tree builds itself by pulling out carbon from the co2 in the air

Re: When somebody loses weight, where does the fat go?

#59

Post by beardbandit »

yetihehe wrote: post #47
arkh wrote: post #13

Earlier quoted context omitted.

It's easier to eat less calories than exercise.

Have you tried it? I did, it's easier only for some time. After you lose about 6-7% of your body weight it's very hard to eat less, your whole behaviour changes.

Being 100% sedentary + eating less calories is pretty difficult.

For some reason unbeknownst to me, exercise makes eating less a lot easier.

Re: When somebody loses weight, where does the fat go?

#60

Post by zappo2938 »

mikeash wrote: post #4

For anyone coming straight to the comments looking for an answer to the question: it turns into CO2 (and a bit of water) and you breathe it out. When you realize that you have to breathe out all the weight you lose, I think it gives you a bigger appreciation for how difficult weight loss can be.

I sometimes ask the deep philosophical question, why does a tree not sink into the ground it grows out of? It blows people's minds when I explain that the reason is because the tree is mostly water and CO2, a gas and a liquid coming from the sky.
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