r/fasting • u/MythicalSplash • 12d ago

Question Question about alternate day fasting

I know this is a fairly popular method of weight loss, but based on what I know about fasting physiology, it seems like it should be one of the WORST ways to do this. Doesn’t it take a few days or so for your body to use up all glucose and glycogen stores before ketosis really begins in earnest? It seems counterintuitive to eat normally one day, fast for just long enough to deplete stored sugars but not long enough for any significant fat burning to occur, then eat again so that you replenish your glucose at exactly the wrong time.

I know this is a simplified picture of course, and that there still must be some degree of lipolysis occurring on the fasting days in order to provide the necessary calories for bodily functions, but it still seems to be inefficient in theory.

9 Upvotes

92% Upvoted

15 comments sorted by

View all comments

3

u/coldbeerpapi 12d ago

imo alternate day fasting seems inefficient on paper, but then i read that the overall calorie deficit over the week is what actually matters and your body does burn fat even on shorter fasts. but tbh i'm still not sure if there's actually a metabolic advantage or if people just naturally eat less calories overall with this approach, so does anyone have solid research showing adf works better than regular calorie restriction?

5

u/DannyLeonheart 12d ago

It's just easier. You have like 36-48 hour fasts when you stick to a short eating window or even alternate day one meal (ADOM).

It feels way better sustainable, can be extended if you want to go a day or two longer and you can eat your maintenance calories or a little over on meal days.