72 hour fast update: done with it, here is the immediate data
Ok so i made it. 72 hours, nothing but water, black coffee, and electrolytes. Here is everything i tracked immediately after breaking the fast before eating anything.
inbody scale: body fat 22.8% (down from 24.1%), skeletal muscle mass 42.6kg (down from 43.2kg), visceral fat level 4 (unchanged). Scale weight down 3.1kg total.
The muscle loss number is the one i was most anxious about and honestly it is less bad than i expected. 0.6kg is not nothing but given that i was completely sedentary for 72 hours and eating zero protein i was bracing for worse.
Fasting glucose at hour 72: 61 mg/dL. Lowest it got. Felt fine surprisingly, no dizziness or brain fog at that point.
Ketones at hour 72: 3.8 mmol/L. Hit meaningful ketosis around hour 18 which was faster than i expected.
HRV: dropped to 51 by day two then came back up to 58 by the end of day three. Interesting pattern.
Energy and mental clarity: day one was rough, day two genuinely surprising, day three felt almost normal. The mental clarity thing people talk about kicked in around hour 36 and it was real.
Breaking the fast with bone broth right now. Will post the 72 hour refeeding scan when i have it.