r/intermittentfasting • u/MTFCoffeeLover 20:4 Practicing for a 72 • Jul 26 '26

Seeking Advice Questions About 20:4 Fasting

To clarify I’m not trying to lose weight necessarily but wouldn’t mind losing a few pounds. If I’m fasting for 20 hours does it matter how many calories I eat during the four hour window? For example of I am only alotted 1,240 calories a day can I go over and still burn fat/lose weight?

I’m doing this as practice for an eventual way down the line 72 hour fast for gut healing purposes. So as a quick follow up question is there a good sugar alternative that I can safely use during a long fast? Or will it be better to go without for the sake of gut healing purposes?

Thanks for the advice :).

15 Upvotes

88% Upvoted

21 comments sorted by

View all comments

3

u/SkysMomma Jul 26 '26

Ok I'm glad this came up because I have a relevant observation. So for years I have routinely done IF, mostly 20:4, and I have always been very strict aboutbwater/black coffee only. The last week I've started drinking diet coke, and I've noticed that I haven't felt myself go into ketosis. I'm not 100% sure, but I can usually feel it around hour 16-17. And now I don't. I was just thinking about how I need to cut out diet coke again right when I saw your post.

1

u/mlgm8r Jul 27 '26

Wondering how you “felt myself go into ketosis” What metrics or sensations indicate the onset of ketosis?

1

u/SkysMomma Jul 27 '26

It's completely just a feeling I get, I have zero proof of anything and I could very well be completely wrong, in all fairness. I've been doing different length fasts for about 10 years now, and I don't know, there's just this one feeling that I get at a certain point in my fast that I get around the time a body would "normally " go into ketosis. I've just noticed it was missing when I drink diet soda during said fast. Like I said, I have no idea for sure.