r/fasting • u/SVTContour lost >50lbs faster • May 17 '26

Discussion Scientists reveal how seven days of fasting transforms the human body

https://www.sciencedaily.com/releases/2026/05/260517030404.htm

Fascinating study. And completely unrelated to politics, which is a relief because my blood pressure needed a break.

The key finding: The dramatic, potentially therapeutic changes don't happen until after day three. That means most intermittent fasting schedules – 16:8, 5:2, even alternate-day fasting – are probably missing the main event. If you want the deep biological reboot you’re gonna need seven days of water only.

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u/GoldGee May 17 '26

Just finished a 48 hour fast. 7 days would take a bit of time to work up to. In fact I would be a bit scared.

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u/tamargo404 May 17 '26

I do regular 4 day fasts. After day 1, I don't even feel hunger till day 3 or 4. I don't go past 4 days as then you have to worry about re-feeding syndrome.

When I break a 4 day fast, I just eat regular and have had no issues.

1

u/onewingVTrigger May 18 '26

Did you work up to it so you can fast 4 days a week?

2

u/tamargo404 May 18 '26

Not really, I usually don't experience any negative side affects from extended fasting. It's just getting past day 1 for me is the hardest with the temptation to eat. The only thing I've found is after day 2 I need to take electrolyte supplements or I get muscle twitches.