December 2018 ZORNFAST


tl;dr: I am just over 88.5 hours into my first extended fast. My goal was 72. I’m planning to break the fast within the next couple of hours. I’m feeling pretty good and can feel the changes in my body.

I started keto about 27 November of this year. This is after many years of being wheat free and relatively low carb. The past few years have been very stressful and I had put on more than 20 pounds in the last 3 years. 8 of those pounds since October of this year.

Keto flu actually hit me quite hard. Salt and other electrolytes helped some but not enough. I started thinking that I wasn’t eating enough, so upped my minimum calories to what is supposed to be my TDEE, and sometimes 200-300 calories above that. It did not cause me to gain weight and I felt better. Notably my problem tends to be undereating, but then bingeing because my body is like you haven’t eaten enough. I don’t really get strong hunger cues. So I’ve always naturally skipped meals. Once I upped my calories purposely, my appetite increased, which is good.

I’ve always thought I was insulin resistant and that’s why the trouble losing weight. I don’t know if anyone experiences this, but I can feel it in exercise as a heaviness in my thighs and upper arms as I continue to exercise, even just walking. After starting keto, I was able to start doing about 50 minute walks again. After a few days, I realized that when walking fasted, I wasn’t feeling that heaviness.

Then I started researching insulin resistance and came across extended fasting and it’s effects on insulin. I also noticed that, right after my fasted walks, my blood ketones would be a bit higher, along with my bg, but bg would drop down not much later.

I know this is long, but it was my path to trying my hand at extended fasting. As of today, I think my body is getting the idea. I’m planning on doing some 24-36 hour fasts during the week, along with 18/6. And then doing my moderate extended fast once or twice a month. I’m looking forward to seeing how things change.

Thanks to everyone for sharing their experiences and all of the wonderful info here. It’s what has really helped me to get to this point.


One day after my 91.5 hour fast and I am down 8 pounds. I’m sure I will gain more than half of it back. I’m just excited to have broken through that threshold and to have found a tool that really may help me get back to my ideal weight. I’m also 12.5 pounds down since I started keto about 36 days ago. This is a great way for me to enter into the new year.

(8 year Ketogenic Veteran) #143

This is not recommended by me and my colleagues. After an extended fast it’s important to refeed for a minimum of two days, at least two meals each day. Then launch into another long fast

(Kevin Ruther) #144

What’s the thought process behind the refeed window of two days?


Kevin, I did EXACTLY what you are considering. It was pretty hard, and I’m an experienced faster. Mine wound up,about 76 hours, a single, 4 hour re-feed, and 108 hours.

Did I already say it was HARD???

I won’t do it again, and it wasn’t even a strict, water-only fast. I am in maintenance about a year now, and I do “dirty fasting” nowadays. ([spoiler]Cream in my coffee, primarily[/spoiler]…about 2-3 hundred calories worth daily.)

I can’t answer your question, scientifically. But 100 pounds ago, I could fast for days on water only. (No more!) I went for 11 days in April of 2017…nothing but water and [spoiler]tea.[/spoiler]

(8 year Ketogenic Veteran) #146

You are so funny @goldwingnut

You can write out the word tea in here you don’t have to blur it LOL

(8 year Ketogenic Veteran) #147

I’m starting day 3 of a 5-day water fast. I will break it on Saturday, refeed for 2 days with two meals each day, and then launch into another 5 day next week.

(8 year Ketogenic Veteran) #148

Not thought process, science. If you’re not re-feeding properly it becomes calorie restriction. You know the old calories in calories out theory that has helped to make the USA overweight? CICO. The eat less move more bullshit.

Special biological hormonal processes begin when we are in the complete absence of food. When we’re giving our bodies a small amount of food this process is doesn’t kick in. A small amount of food as in only refeeding one meal between extended fasts.
When we fast adrenaline is released, and metabolism actually speeds up.
Read The Obesity Code by Dr. Jason Fung. Or visit his website at

(8 year Ketogenic Veteran) #149

Full fat adaptation takes at least six weeks. I wouldn’t have recommended an extended fast yet but if you’re able to do it it won’t hurt you.

This you were probably exactly spot-on about this. I find more issues with people and under-eating! It’s a hard concept to wrap your head around to eat more in order to lose weight. But that’s what it comes down to with many people. You need to refeed properly to keep your metabolism running at top speed. And if it’s broken? You can fix it with proper amounts of refeeding over an extended period of time.

(Brennan) #150

@Brenda is there a January 2019 thread yet?

(8 year Ketogenic Veteran) #151

No. I’ll set one up now. Even though the official ZornFast doesn’t start until the third Thursday. But everybody’s been posting all types of different fasts all the time including me. So I will start one right now. I will add the link to this comment as soon as it’s ready. Or just look under ZornFast and you’ll see January 2019 there.

(KCKO, KCFO) #152

Curious, what is your goal for doing this? These 5 dayers are adding up to a lot of fasting.

Self discipline?
Trying to drive your weight’s set point down?
Kick up metabolism?

(8 year Ketogenic Veteran) #153

My metabolism is great I just had an RMR done. It’s an experiment. I’ve never done extended fasts back to back.
It’s turning out to be really great for me because I’ve been breaking weightlifting records of my own. I’ve been fasting for years and I’m always changing things up. I had actually meant to do four 5 day fasts in the month of December but stress prevented me from fasting for a few weeks.
I had a dexa scan before I started all of this and I want to see how this helps build lean mass. I do have some body fat I would like to move but it’s not imperative. Basically I’m going to see what happens. I love a challenge.

(8 year Ketogenic Veteran) #154


@Brenda Thanks for your comments! Yeah, understood about the timing of my fast. Like I mentioned, I have trouble with eating enough because I don’t get clear hunger signals. So it’s always been easy for me to skip several meals or a day of eating. To eat at my TDEE, I was forcing myself and couldn’t keep up with it. So my metabolism is definitely broken. That’s what has brought me from a paleo/primal eating style to keto. I’ve also been wheat (and most other grains) free for several years. And pretty low carb until the stresses of the past year. Maybe that helped me some. My main issue is with hydration and electrolytes. Still trying to dial that in.

I figured I would try the fast because at least my body might recognize it as fasting versus the calorie restriction since I haven’t been able to keep up with the eating to even get my body to recognize fat adaptation. Plus I didn’t feel like I could eat anymore on the day I started the fast. (I have done cleansing fasts in the past.) And I thought maybe my body would do something different in a fasting situation. I told myself I would stop if I had any problems. But something needed to change.

I’m definitely going to work on refeeding before I do my next 72-90 hour fast. But I do feel that my body responded really well, particularly just after the 72 hour mark. Right about then, I was really cold, and just about at the end of clearing out my bowel system. I went to bed with a hoody and scarf, and my regular heated cherry pit pillow (which I use every night anyway). In the middle of the night, I suddenly warmed up and haven’t really gotten cold since then. And I felt so great when I woke up, I didn’t want to end the fast. I made myself stop at 91 hours though because I didn’t want to overdo it. I actually feel better fasting than regular keto-ing. I need to sort that out.

I definitely wouldn’t recommend an early start to EF for everyone, but it seems to be something that worked for my n=1 body to break the inertia. I do have a strong focus on alternative healing (for humans and horses), so am hyper-aware of my body.

Thanks again for your reply. I’m so grateful for all of your wonderful information.

(8 year Ketogenic Veteran) closed #156