how long does it take fat to be removed from your body?

SLLRunner

When the fat leaves the body does it get replaced with muscle? I know answering a question with a question. sorry.

I don't think so. Muscle is built from resistance training.

UrbanEmby

On average what you do today you will see the effect about 3 days later weather you add weight or lose weight.

thecharizardtamer

Thank you, I learned a lot today!

eggomylegos

In for science...

1princesswarrior

I may be wrong and this is too much science on a Sunday afternoon but I always thought the only way to get rid of fat was through surgery.

Don't fat cells just reproduce once they reach a certain size? Can't we shrink them but never get rid of them? Unless of course you know a good plastic surgeon.

jimmmer

There's a paper by Alpert et al that claims the maximum amount that can be liberated from fat stores is 31.4 cals/lb/day. I've never read the paper and don't know if it's good science or not, so there's that.

So the maximum deficit according to this would be dependant upon how much fat mass you're carrying. And that's different for everyone.

This would suggest that the leaner you are, then the smaller the deficit you need to run in order not to chew up your lbm. But people doing heavy lifting with high protein have routinely claimed to lose fat with large deficits and not drop muscle mass, so there's that.

So you can chose to believe a single paper you've probably never read or a bunch of anecdotal reports.

PennyVonDread

When the fat leaves the body does it get replaced with muscle? I know answering a question with a question. sorry.

I don't think so. Muscle is built from resistance training.

AND a calorie surplus or at least high protein at about maintenance. Muscle is not easy to gain, it takes serious work and a caloric intake. Granted, burning fat will make the muscle you already have more visible ("toned" look) but it's only more apparent because it's not hidden under a layer of fat.
That's not to say you should only lift weights when you're trying to build muscle, though. Lifting at a caloric defecit during weight loss helps boost metabolism (even for hours after you're done lifting that day), increase strength (which is NOT the same as muscle MASS, function=/=size) and helps retain muscle mass so that your weight loss is FAT loss, not muscle loss. Serious calorie restriction can break down musce, fat, and bone tissue for energy, so the weight loss efforts are actually hindered after a while because having muscle mass effects metabolism. I think what more people are really aiming for is a reduction in body fat percentage, not just "weight" loss but emphasis on fat loss.

randomtai

I may be wrong and this is too much science on a Sunday afternoon but I always thought the only way to get rid of fat was through surgery.

Don't fat cells just reproduce once they reach a certain size? Can't we shrink them but never get rid of them? Unless of course you know a good plastic surgeon.

Now I have heard everything. :noway: :noway: :noway: :noway: :noway:

LAT1963

I may be wrong and this is too much science on a Sunday afternoon but I always thought the only way to get rid of fat was through surgery.

Don't fat cells just reproduce once they reach a certain size? Can't we shrink them but never get rid of them? Unless of course you know a good plastic surgeon.

I'd better go look that up because I forgot exactly what happens. Fat cells tend to just get bigger, not reproduce; now humanity is learning about stem cells it seems more likely that stem cells differentiate to add to the number of fat cells when there's excess food, rather than the fat cells themselves dividing.

Most non-neural tissue types have a rate of dying off and being replaced. It's possible long-term that the natural attrition of fat cells isn't replenished if you don't over-eat--there may be a natural way to lose fat cells if you are patient over a period of years. But at this moment I don't happen to know the answer.

amusedmonkey

There's a paper by Alpert et al that claims the maximum amount that can be liberated from fat stores is 31.4 cals/lb/day. I've never read the paper and don't know if it's good science or not, so there's that.

So the maximum deficit according to this would be dependant upon how much fat mass you're carrying. And that's different for everyone.

This would suggest that the leaner you are, then the smaller the deficit you need to run in order not to chew up your lbm. But people doing heavy lifting with high protein have routinely claimed to lose fat with large deficits and not drop muscle mass, so there's that.

So you can chose to believe a single paper you've probably never read or a bunch of anecdotal reports.

Interesting, but is that 31 calories per pound of body weight or per pound of fat? Because if it's per pound of body weight you run the issue of certain organs and structures having different calorie uptakes, not to mention the maximum deficit would be very large even for a tiny 100 pound woman.

If it's per fat, does that mean that women can handle a more steep calorie cut than men before the body starts tapping into other kinds of tissue for energy because they naturally have more fat?

Edit: Does this work both ways? In the sense that if there is a maximal amount fat to be burned per day is there a maximal amount for storing it?

I may be wrong and this is too much science on a Sunday afternoon but I always thought the only way to get rid of fat was through surgery.

Don't fat cells just reproduce once they reach a certain size? Can't we shrink them but never get rid of them? Unless of course you know a good plastic surgeon.

If you're asking if the body can get rid of fat cells, I'm not sure, I would need to read more about the subject. If your question about fat itself, yes, you can get rid of it. That's why the cells shrink when you lose weight, because they lose some of the fat substance in them.

ElkeKNJ

Here's an explantion from "How Stuff Works":

Hormones regulating our blood sugar levels activate an enzyme in the blood vessels of fat tissue called lipase. Lipase ignites fat cells to release macromolecules called triglycerides, which are what make fat cells fat. Triglycerides are made of glycerol and three fatty acid chains. When they receive the signal from lipase to exit the fat cells, the triglycerides break up into their respective components and enter the bloodstream for use. The liver snatches up the glycerol to break it down for energy, and some of the fatty acids move to the muscles that can farm them for energy as well.

This action of breaking down triglycerides into usable energy is called lipolysis. Once inside the mitochrondia, or power source, or muscle or liver cells, the components of the glycerol and fatty acids are shuffled and reshuffled to harness their energy potential, producing heat, water, carbon dioxide and adenosine triphosphate (ATP). ATP hauls potential energy in its molecular bonds for use when we exercise like cellular carb loading. The water exits our bodies as sweat and urine, and we exhale the carbon dioxide.

Waw, I still don't understand everything of this, but maybe I should take better care of my body and stick to the healthy eating this time around. It does sound like a very intricate and therefore sensitive machine, and I better not feed it too much garbage anymore.

AvonBell

Fats are hydrocarbons, molecules of hydrogen and carbon atoms. When your body needs to dip in to its energy reserve your muscles and liver metabolize the fat and break its molecular bonds which releases energy. This is the energy your body uses.

What you're left with is loose hydrogen and carbon atoms. The hydrogen atoms combine with the oxygen in your body to create water. The water is used by your body and excreted in the usual ways (i.e. sweat or urine). The carbon atoms also combine with oxygen to create carbon dioxide. You exhale carbon dioxide. Of course, all of this oxygen comes from the air you breath.

That's what happens to fat.


How long does it take? Well, it's a constant process. You are always shedding water and exhaling. Not all the water and carbon dioxide in your body come from the metabolization of fat. But if you are at a calorie deficit and your body needs energy some of it will come from fat.

dpwellman

how long does it take for that .25 pound worth of calories to be removed?
when you exercise does the fat just disappear from your body? or is it broken down into metabolic waste but you'll still weight the

Fat doesn't disappear, it just gets smaller.

AvonBell

It's the molecules inside the fat cells that are lost causing the cells to shrink.