How fast does fat expand?

(John) #1

I just finished a 65hr fast. Day zero with no carbs, then 65hrs without any calories.

My theory is that gorging after a fast overloads shrunken fat cells, which forces the body to create more fat cells. So I ate a smaller meal to allow them to expand again. But I’m so hungry. I don’t know if I have the will to not eat a nice big meal with lots of carbs. The plan was no carbs today, then carbs tomorrow, but this has run me down.

I think I might wait a few hours, then have that big carbed-up meal.

(Katie the Quiche Scoffing Stick Ninja ) #2

I am so confused by what you are trying to achieve.
Why would you carb up?
You don’t make more fat cells, your existing ones expand.


Yep. It can be complex at times and hard to figure our bodies. It shows why we have to keep experimenting with our metabolisms.

I try to keep changing it up. But I have learned, like you, that I can’t just carb it up after fasting or my gut swells back up. Re-feeding a little slower helps me.

I’m on hour 46 of an open-ended, water-only fast — maybe 3 to 6 days — and am planning to try just a big green salad on first eat-day back. I can’t call it a feast day because feasting won’t work for me. Then I will focus on more protein the second day back.

Not trying for me is not an option.

(John) #4

According to my nutrition professor and a few online experts like Dr. Layne Norton, that if you eat too much too fast, your fat cells won’t be able to absorb the fat. this forces the body to create more fat cells, which essentially makes you fatter. I’m not keto, I’m here for the fasting.

What do you mean you don’t make more fat cells? I’ve heard from numerous nutrition experts that the body makes more fat cells if they can’t expand enough to absorb the fat or carbs being consumed. Do I need to dig out some studies?


Here’s an example of how re-feasting can get to me.

Tailgated at the LSU-Bama game on Saturday and ate keto-well until the dessert came out— caramel apple pie. I had skipped Halloween treats, so broke down and ate two large slices — so good.

The I had another piece after the game to drown my sorrows after Bama kicked our butts. Immediately began water fast at 10:30 that night.

Still, come Sunday morning … weight up nearly 4 pounds (216.4 lbs). I could make a dent in my shins. And I was constipated (like LSU’s offense Saturday).

Earlier today, 36 hours later after peeing seemingly solid for all of Sunday and making a potty call, my weight was already down 5.5 pounds (211.2).

Shrinking and swelling of the fat cells seems to be an ongoing battle for some of us. But if I continue to EF more on than off, my metabolism gives in and burns up a few pound of fat cells. (down 44 pounds total since April.)

Kind of like it’s supposed to work.


Apparently some people can make more fat cells & thus safely expand their adipose stores but others cannot. If you cannot make new/additional fat cells & overfill the ones you already have then they will become dysfunctional & you develop metabolic derangement.

(Diane) #7

If I understand corrctly, it’s more likely that your weight will go up right after a fast due to the rehydration that goes along with replenishing your glycogen stores in your muscles and liver than due to regaining fat. Fat gain after a fast takes considerably longer to show up than fluid retention.

(Ethan) #8

No. You do not add or subtract from the number of fat cells you have as an adult. You can physically destroy fat cells through freezing so that they will not come back. You recycle fat cells, but you won’t add or subtract to or from the total you have.


Apparently some people can add more but most of us seem to stay stable.

(Janelle) #10

That’s kinda sad. You shrink your cells but they’re just lurking there - waiting for you to fall off the wagon! :cry:


Yeah but having larger fat cells that can hold more is actually beneficial to your metabolic health - you can gain weight without them becoming dysfunctional & leading to metabolic syndrome. I suspect I either have too few or the ones I have can’t hold much because I developed prediabetes at a low bodyweight.

(Ethan) #12

The article seems to indicate that adults don’t add more


There is this from Gabor Erdosi
And this[uid] was referenced in the article.


Sorry to bring up an old topic, but does fasting really help you? 80% of all advice on forums is not to practice it for more than a day due to health risks. Why then do you choose such a weight loss option?

(Robin) #15

As with many things, you’ll get contradicting answers/opinions galore…
It rarely hurts to try anything and your body should let you k ow how/if it works for you. The only fasting I do One Meal a Day.

(Laurie) #16

Hi @Ortantyun . Maybe it depends on what you’re eating. Some believe that fasting works well in combination with keto.

Most days I eat 2 meals, within a 6-hour window (lunch at noon and supper around 5 pm). This is considered “intermittent fasting.”

(Bacon is a many-splendoured thing) #17

A lot of people find fasting helpful, but it if doesn’t come naturally to you, then don’t force it. Our bodies experience a certain amount of irreducible daily nitrogen loss, and if we are not eating, then the nitrogen has to come from proteins already in the body, i.e., our muscles.

The world’s longest recorded fast lasted for 382 days, and was done under medical supervision. The patient took daily and weekly vitamin supplements and was regularly tested for all sorts of potential problems. He was so obese at the start that he had enough extra muscle (to cart all that bulk around) to be able to afford a healthy amount of muscle loss. He went from 207 kg/456 lbs. to 82 kg/180 lbs. and was able to maintain a normal weight for the rest of his life. (“Features of a successful therapeutic fast of 382 days’ duration,” W. K. Stewart & L W. Fleming, Postgraduate Medical Journal (March 1973), 49:203-209.)

Such an extended fast is not something to attempt on one’s own, however. In fact, even Dr. Jason Fung, the fasting guru, does not advise fasting longer than three or four days without medical supervision.


I can’t imagine why people consider it dangerous in general but they have the right for their opinion I suppose…
People are against OMAD, IF in general and keto too, very much. I don’t care, I follow my own body and knowledge, other people’s experiences matter to me somewhat too…

It’s not necessarily for fat-loss, tons of people do it for autophagy or challenge, spiritual reasons etc.
It probably would help me with fat-loss as I am super bad at eating at a deficit without a full fast - but as I couldn’t do more than 1-2 days a year if I got lucky, it wouldn’t be important for my fat-loss. I want autophagy and prove that I still can fast… I could, it was automatic on high-carb, a bit hard on low-carb and impossible now :frowning: I want it back. Just a bit, 2-3 days at most, I don’t consider long ones good for me and my tiny muscles (and slight paranoia regarding them, I couldn’t do 2 fat fast days because I was worried about protein. maybe that’s a bit much but we do need it and we can’t pull off a longer fast without muscle loss). But 2-3 days? Quite fine for many of us (if we can pull it off, suffering for days isn’t healthy even if we have plenty of fat to use. I am a hedonist and can’t force myself, it’s either smooth and easy and enjoyable and without any particular hunger or it won’t happen). Not everyone, sure. It’s wrong saying a shorter EF is unhealthy and it’s wrong saying ketoers should do at least IF. Nope, we are all different, we should do what is okay for our individual body. Sometimes a bit push is fine too :wink: Sometimes we need a little push instead of eating whenever, whatever. I am very much against very forceful fasts where we suffer and ignore our body signs. I was on forums where I was the only one who told the faster who had serious pains from hunger and blew up on their boss due to being hangry that they just should eat. No, the others all gave them pep talk about being strong and proud of all the suffering… It wasn’t just some mere hunger… The same forum had someone who decided on a quite long fast while being underweight… It didn’t end well but the ambulance arrived in time… Many people aren’t very smart and knowledgeable and push too much.

(Bacon is a many-splendoured thing) #19

Muscle loss and electrolyte imbalances are a couple of reasons to be careful when fasting longer than three or four days. If you read the article I cited in my earlier post, you will learn what some of the dangers are that Mr. Barbieri’s doctors were on guard against. At various points during his fast, he needed supplements of various minerals, and he was on a daily vitamin supplement, as well.


Yeah I wrote I am the same, don’t like the idea of long fasts. I talked about shorter fasts. Even OMAD is called dangerous by many but I see no problem with infrequent 1-2 fasting days if the one in question handles it well.
But @Ortantyun wrote “more than a day due to health risks” so I replied to that. More than a day but less than 3. That’s my elusive target in the last few years.

Aren’t electrolytes easy, people who need it just should take something? I never needed sodium for the first 3 days so I don’t need to worry about that (or rather it depends on the circumstances but I know what signs requires supplements in my case).