The fasting journal · matched to fast day 16
Day 16. Autophagy, The Real Reason John Is Doing This
Day 16 opened with an apology and ended with a science lesson.
24.9 pounds in 16 days
The scale said 203.7 this morning. Started at 228.6, so that is 24.9 pounds gone in 16 days, another 0.6 since yesterday, 10.9 percent of my starting weight. Body fat percent is down from 42.3 to 35.5, muscle percent up from 34.5 to 36.2. Every reading lives on the bloodwork page.
One housekeeping note first. Yesterday’s recording had slightly blurred numbers on the scale shot. The posted numbers were correct, the sheet and the site said 204.3 and today’s recording is clean. When you publish every number every day, you own the fuzzy takes too.
The two reasons
People keep asking why a 90 day fast. Not 30, not 40, which I have already done. So today I want to touch on the two reasons I am doing this.
The first is the obvious one, the fat burning. You can tell I am shrinking and shrinking. I am losing the fat, which is good for my body, because I need to lose the fat anyway. Sixteen days of numbers back that up.
The second reason is the one I actually care more about.
Autophagy, the self cleaning cycle
Autophagy is the self cleaning mechanism everybody has built inside them. It helps cells break down and recycle their own damaged parts. My liver cells are cleaning themselves out. My skin cells, my kidney cells, even my brain cells are doing the same work. That is how I think about what these 90 days are for. The weight is the visible part. The cleanup is the reason.
Here is the honest science layer, because this site does not do magic claims. Autophagy is real and it is serious biology, the discovery of its mechanisms won the 2016 Nobel Prize in Physiology or Medicine. Fasting is one of the main levers researchers use to turn it up, when nutrients stop arriving, cells start harvesting their own worn out components for fuel and spare parts. What science has not settled is the human dosing, how much fasting produces how much autophagy in which tissue. There is no strip or blood test that measures it directly, so I do not put a number on it. My ketone strip I can show you, it has been parked at the top of the chart since day 8. The autophagy I take on the research.
The DMs on this topic split into two camps, people who have never heard the word and people who have heard too much, exact hour countdowns, guaranteed benefits. Both deserve the same answer. The process is real, fasting turns it up and anyone selling you a precise human timeline is ahead of the evidence.
Day 16 done
Sixteen X marks on the calendar. I feel good, I feel great and the weekend sun is out. That being said, I am gonna let you guys go. Enjoy the rest of your weekend. Cheers.
This is a doctor supervised fast with baseline bloodwork on record. Do not attempt an extended fast without medical supervision. John built up to this over 15 years of shorter fasts.
Quick answers
What is autophagy?
Autophagy literally means self eating. It is the process cells use to break down damaged or worn out parts, old proteins, broken mitochondria and recycle them into fuel and building blocks. It runs at a low level all the time, it is basic cell housekeeping. The mechanism was worked out in yeast by Yoshinori Ohsumi, who received the 2016 Nobel Prize in Physiology or Medicine for it. Scientists study it because it appears to matter in aging and in several diseases, though most of the detailed evidence still comes from lab and animal research.
Does water fasting trigger autophagy?
Fasting and calorie restriction are the classic triggers researchers use to ramp up autophagy in lab and animal studies. The logic is simple, when no nutrients come in, cells switch to breaking down their own damaged components for energy and raw material. What is much less settled is the human side, how strong the effect is, in which tissues and on what timeline. There is no blood test or urine strip that reads autophagy the way a ketone strip reads ketones, so anyone who gives you an exact number is guessing. What John can verify is the fasting state itself, his ketone strip has read at the top of the chart since day 8.
When does autophagy start when you fast?
Nobody can give you an honest exact hour, because autophagy cannot be measured directly in a living human the way glucose or ketones can. Animal studies show it ramping up within a day or two of food stopping and it scales with how long the fast runs. It is also never fully off, your cells do this housekeeping every day at some level. The claims you see online, it starts at 16 hours, it starts at 72 hours, are extrapolations from animal work, not measured human timelines. John is 16 days in, deep in ketosis by his strip and the rest he takes on the research, not on a gadget reading.
How much weight has John lost in 16 days?
24.9 pounds in 16 days, from 228.6 down to 203.7, which is 10.9 percent of his starting body weight. The daily drop has settled into a steady rhythm, 0.6 pounds since yesterday. His body fat percent has moved from 42.3 to 35.5 while muscle percent went from 34.5 to 36.2 on his home scale. Every daily reading is published on the bloodwork page and the fast runs with baseline labs and doctor supervision.