Going long

Sunday, November 03, 2019

Most of the fasts I've done have been 16 hours long using the "16/8" method. I've done a handful of 20 and 24 hour fasts but after 16 hour fasts, the next most common for me has been 36 hours. I stop eating after dinner on day one, don't eat at all on day two and resume eating with breakfast on day three.

I've toyed with the idea of doing a much longer fast. Longer fasts have more "power" because after the first 24 hours the body's glycogen stores are pretty much used up and the body must burn fat to fuel itself. (There is some breakdown of protein but the idea that your muscles waste away during fasting is a myth. I can go into that in another blog if people want to hear it.) Burning ectopic fat in the liver, pancreas and even between the fibers of our muscles helps reverse conditions like non-alcoholic fatty liver, which usually precede type 2 diabetes. But I also just want to see what it's like.

My longest fast to date has been 80 hours. I felt fine the whole time. The longest fast on record is 382 days. A Scottish man, weighing 456 pounds was advised by his doctors to start a short fast to quickly improve his blood chemistry. He found that he didn't mind fasting and the results were amazing, so he just decided to keep going. The fast was medically supervised and he had blood work done every day. In 382 days he went from 456 pounds to 180 pounds. And here's the clincher: in a follow-up several years later he weighed 196 pounds, so he not only lost over 250 pounds, he kept it off.

I want to try a longer fast. Not 382 days … I was thinking at least a week, maybe two if I can make it. I did a three-day fast earlier this week and felt great. I had dinner last night and now I'm twelve hours into this longer fast.

The nice thing about fasting is that you are not locked into anything. You can decide to start eating again at any point. So if I feel poorly at all, I'll just stop. I'll be monitoring my blood sugar four times a day, my blood pressure once a day and my weight daily. If any of those data are off, I'll stop.

When I do fasts of 48 hours or less, I just drink water, black coffee and tea. Longer than 48 hours I worry about electrolyte loss (salts lost through urine, sweat, etc.) so I add one cup of chicken broth a day (lots of salt). That has 30 calories, so purists would say I'm not fasting, but 30 calories of protein a day will not shift my metabolism back to a feeding mode, so I don't care.

Wish me luck. I'll give you a progress update next Sunday.

P.S. I just want to add this, because I think it is really important: this is my blog, not "how-to" medical advice. I have a PhD in biology, I have been researching metabolism and fasting for quite some time, and my health care providers know I'm fasting. If you are intrigued by what you are reading here, please talk to your doctor first. SOME PEOPLE SHOULD NOT FAST. If you are pregnant, if you have a history of eating disorders, if you are on insulin (unless you talk to your doctor about adjusting your meds) YOU SHOULD NOT FAST. And that's not a complete listing of situations where fasting is contraindicated. So please, don't take medical advice from some random guy on the internet. Talk to your doctor.
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Member Comments About This Blog Post
    Good luck! My longest fast is 89 hours (3 days, 17 hours). I want to try a 5-day fast soon; probably next week as I will have the chance then with minimum distractions. I've bought some bone broth from the store as a crutch should I need one. I truly wish you the best on this journey! I'll be looking forward to hearing your experience.
    emoticon Teresa
    592 days ago
    From everything I've read, I thought that fat burning starts before hour 16 if you have been fasting every day and have depleted your glycogen stores over time. How else would you account for the results people get from 16:8? I realize it ramps up when you go longer, which is why I've switched to 19:5, but personally I just can't imagine doing the extended fasts. Good luck!
    593 days ago
    A question: How do you cope with the aromatic aroma of cooking foods? I do fine until I smell something cooking, then my belly begins to growl and demands to be fed. Suggestions?

    emoticon emoticon
    593 days ago
    An interesting post, and some well thought-out experiments that you are attempting.
    593 days ago
    Sounds like you are well prepared, and tracking some metrics to ensure you don't run into problems. Best of luck, I hope you do well in your fasting plan.

    And like Linda058 said, thanks for the last paragraph, it's important for people to manage their diets and lives responsibly, and not follow random internet advice! emoticon
    593 days ago
  • no profile photo INCH_BY_INCH
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    593 days ago
    Very interesting
    593 days ago
    593 days ago
    I love fasting...do 16-18-20 several days a week.
    My problem is all the people I feed every day so I am shopping, preparing and cooking for hours a day.
    My dear man and I live alone so I would feel bad making his dinner and not eating with him.
    The 36 hour fast sounds do-ab,e.
    I learned sooooo much from Jason Fung and dietdoctor.com
    593 days ago
    Interesting. emoticon
    593 days ago
    Thank you for adding your advisement. IF isn’t for everyone
    593 days ago
  • no profile photo CD1987279
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    593 days ago
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