Fasting and COVID-19

We have been getting a lot of questions about what you should, and should not be doing regarding your fasting practice and general health in the midst of the COVID-19 pandemic.

We worked with Dr. Peter Attia, to lay out a plan of action for Zero users. Here is what Dr. Attia suggests based on the best available information. 

Peter Attia breaks down fasting benefits and risks during the COVID-19 pandemic and discusses how to be mindful of your nutrition during self-isolation.

Two things you should and one thing you should not be doing.

1.Do continue your normal daily nutritional routine 

Your normal time restricted feeding practice(for instance a 16:8 or 18:6 eating window) shouldn’t pose any risks with regards to COVID-19. 

If you already have healthy routines, stick with what you are doing. While there isn’t sufficient evidence to say if shorter fasts will help with regards to COVID-19, maintaining routines is important during times of uncertainty.  

2. Consider holding off on multi-day fasts for now

We’re being abundantly cautious here, but there’s some evidence that a longer fast (2+ days) can cause a cortisol spike which could temporarily dampen your immune system. In normal times, once the risk of contracting COVID-19 has abated, prolonged fasts can have profound health benefits, but now may not be the ideal time. 

3. Do everything you can to buy time

Scientists and researchers need time to develop vaccines and/or antivirals. Buying time delays the spread of the disease, which avoids overwhelming the hospital system. This is what is referred to as “flattening the curve”  (see figure, below). Buying time also allows for a better understanding of the impact of COVID-19, including any possible long term, unknown effects.

The best ways for you to buy time are to be maniacal about washing your hands (it is very important to lather with soap for at least 20 seconds prior to rinsing your hands with water)  and practice social distancing.

Social Distancing 

A lot of people are talking about social distancing, but we think it’s important to get into the details of what this means. 

The main objective is to keep your distance from other people and avoid large crowds. Practically, this has a big impact on your day-to-day life. This means avoiding public places where you don’t have control over your personal space like movie theaters, bars and restaurants. It also means working from home if possible, avoiding busy times at grocery stores, and considering solitary or at-home workouts vs going to a public gym. 

Across the board, infectious disease experts agree distancing is the number one way to mitigate the impact of COVID-19. Everyone has a unique circumstance, not everyone has the option to work from home or avoid social situations, but wherever you can, keep your distance. From a health perspective, the downside of isolating is minimable and knowable, while the upside is significant.

The Zero COVID-19 Resource 

At Zero, our mission is to help people live a longer, healthier life. That includes uncertain times like these. As part of that commitment, we will be updating our COVID-19 page whenever there is new, relevant information.

Note: Comments for this post are open but are held in moderation.


Posted in Zero News


  • I just want to say THANK YOU for the constant and concise updates. They have been more helpful than you know. Thank you!

  • Thanks for the info guys. I’m choosing to still do my 36 hour weekly fasts as I am avoiding populated areas and feel in my local area that is still more beneficial for my overall health rather than risky at this point.

  • Thanks a lot for the information due to fasting and corona.
    I’m from Germany and I’m coming to the end of my 10 day fast. I’m gonna finish as long as I feel good with my vegetable broth full of nutrition.

    • What if you’re sick?
      I’m not infected with the covid19, but have a cough and wouldn’t want to be at a higher risk of contagion, should I still be doing 16/8?

      • There are several sources online that say you should not fast if you are sick regardless of what you are sick with. Your body needs to heal when you are sick. If you absolutely feel the need to continue fasting, do a shorter fasting window say 12 to 14 hours instead of 16.

  • Excellent information. It never occurred to me that an extended fast could potentially compromise my immune system, and as much as that concerns me, it has taken me two years to master and achieve longer fasts, it is the only way in addition to a healthy lifestyle I have been able to lose weight. If I go back to shorter fasts this may interfere with my weight loss:(. Idk what to do. Going backwards is a tough choice 🙁

    • I’m curious Esther. How long are your daily fasts? I’ve been only fasting for about a month daily 16:8 but I always find myself doing average of 18 a day.

    • I am going to switch to alternate day fasting from my 5-6 days a week fasting and up my zone 2 exercise. What I found that works for me is higher doses of melatonin. This shuts off the insulin production in the pancreas. I actually can lose weight finally eating OMAD keto. I started with 12 mg to get use to it and experimenting with 24 and 36 mg. Good Luck!

    • I’ll continue with every other day feeding myself with a fasting window of approximately 2h and ~46h between meals.

  • Thank you so much for this update. Our church has encouraged us to fast every Friday in a way of prayer for the COVID-19 situation. I am really pacified with the idea that I could continue doing IF and add my friday fast. Praying for everyone’s safety and health. 🙏💜

  • Great piece of information there amongst the current cacophony of misinformation and theories around us. Keep up the good work.

    Namaste from India!

  • I appreciate your info on virus. I’m currently on my 78 th fast and on a 23/1 fast. I can easily drop down to 20/4 and maintain there. Everybody stay safe. Wash hands and keep distance!

    • Just curious. If you have a daily eating window at 1hr, are you able to eat enough? I find it pretty hard to eat enough if I have too small eating window and don’t want to get in too much calorie deficit. But maybe it’s just a training thing to be able to eat that much in one go 😛

  • Zero fear. Starting a ten day fast today. Luckily, I won’t need toilet paper in a few days. I am choosing to ignore the media fear mongering and go about my daily life as best I can with everything shutting down around me. When we look back on this in a few months or however long it takes we are going to marvel at the overreaction, I think.

    • It may be the “over-reaction” that controls the spread and enables us to look back on it. As for me, I will not be doing extended fasts & will follow the recommendation of the experts to defend in place. Better to be safe than sorry.

      • Thank you very much for the information. I will keep up my 18/6 fast.

        Please do not forget to use gloves which is more important than masks.

        Stay safe and healthy.

    • It’s not only about you, it’s about all the people you could infect spreading the disease even if you will show no symptoms yourself.

    • My man here is a spiritual warrior. 10 day fast over here also with no fear. Time to upgrade the immune system…
      Stay strong, peace from UK.

    • It’s fine to do your ten day fast as this impacts only you. But please practice social distancing as this impacts the health of the public and prevents spread of disease and protects everyone especially the most vulnerable. …from a seasoned doctorally prepared public health nurse

      • Hi! There is a wisdom throughout the passage of time of the unseen (pertaining to the maintenance of societal health) which has been greatly suppressed due to its potent success over such calamities which has accompanied mankind as long as its conception/creation.
        There are some of us who acknowledge this before even being told, just by simply watching the world and the signs of reality. Fasting is (potentially) one method for the elevation of one’s wisdom.
        Gratitude for your reminder, and peace be upon you: from a Muslim who studies medicine.

    • No extended fast seems to be the consensus from all of the medical doctors that recommended a fasting life style. IThe risk factors different for everyone but it might be a good time to listen.

      • The same majority of doctors who would rush in to prescribe pharmaceutical intervention for otherwise trivial matters. Most of the doctors out there lack deeper understanding of the subtleties of true healing. Peace.

    • It’s not an overreaction. A lot of people are asymptomatic and going about your everyday life, you are spreading it to the vulnerable people… Hospitals won’t be able to cope and will have to make horrific decisions all because people are in denial. Please reconsider your actions.

  • I’ve been wondering about human growth hormone, which has definitely increased significantly for me as I’ve done 42-6 fasts: would it make any sense that childrens’ resilience towards this virus has to do with their increased growth hormone levels? As I think out loud here, probably not, as often kids are more susceptible to infection, but I want to believe that my immune system has improved with my fasting regimen.

    • Not necessarily, nobody knows at this point. Different viruses and strands thereof are more dangerous for different age groups. F. I. the Spanish flu harmed primarily 20 to 40 year olds. For SARS Cov 2 young age seems to be a protective factor…

  • So as a health care professional I’m constantly reviewing the information I know in my field, scrutinizing, learning new information, reapplying and Starting the cycle again. That’s my brain and it’s helped to catapult some concepts in my field. That being said I have a thought about cortisol. It’s it perhaps that due to all of the amazing Mechanisms that are turned on after the first 36-48 hours of fasting, that maybe cortisol has a different role to play during the longer fasts? Maybe with the addition of a rise in serotonin levels and other brain chemistry that is present, cortisol is not the villain we know it to be during stressful times? Hmmm. Just sharing my thought. Please let me know what you think. I’d be interested to know.

    • The cortisol would help me to hunt some dinner, but I don’t need to do that. I need to have a healthy blood pressure. My cortisol was high last week, but I feel much better now after bringing it under control.

      • Cortisol spike is likely due to the ‘changing of gears’ as we humans have bi-fuelled brains, and (can) have access to the gift of gluconeogenesis once our glycogen reserves are depleted totally.

        The stress response can be minimised/mitigated by following the wise protocols of breathing, sunlight, exposure to plentiful quantities of pure water, stretching, movement (metabolic stimulation) and meditation.

        The response may (likely also) be attributed to the moving of lymphatic waste and the clearing of the glandular system (which the adrenals are connected with).
        Peace and best of luck.

  • So when you say more than 2 days , is alternate day fasting ok? Usually ends up being about 42 hours of fasting for me. I’m assuming you are talking about water fasting for more than 2 full days? Just want to clarify 😉

  • Hi there thanks so much about the info relating to the immune system. I just have one comment on your advice about washing hands. I think you meant say wash after your ENTER back into home, after being outside, not just AFTER you leave the house! 🙂 We need to protect ourselves from outside germs.

    • Before and after:
      Eating, answering calls of nature, entering/leaving home, preparing food, using public facilities where physical contact is common, touching others (if you have). Simple stuff 😉

      Cold showers are also great for the strengthening of one’s constitution.

  • DO NOT LEAVE YOUR HOME! Please here in Spain people didn’t take this issue seriously and now close relatives (brothers, parents..) are diying. I chose social distancing more than a week ago, my friends didn’t and they are now infected while I’m not.

    This article is really great! Just what I was looking for. I thought that maybe long fasts could help my body to fight the virus if I get infected. I will continue with my 20:4 fast! Thank you for the info and emphasizing that we NEED to flatten the curve

    Everybody stay safe and healthy

    • Thank you for confirming my thoughts. It is foolish to not listen to the experts. They have every reason to advise social distancing and every reason not to. This advise is not taken lightly. My physical trainer offered to train me at his home after the gym closed. I am very tempted, but I think it is foolish to take a risk–maybe I am a carrier and could infect his home & family and if I am not? only cost me a work-out that I can try to do at home.

      • I will advise you not to bring anyone home. Don’t wait until the government prohibits it, limit your contacts with the outside world as otherwise you will be taking chances of bringing the virus to your own house or to people that are at risk.

        Behave yourself as if you were in a country where everything is shut down, the virus is now everywhere and many people don’t even get tested so they are spreading it without being aware.

        Hope everyone stays at home safe🤗

  • Thank you for the information! Totally respect and appreciate the efforts to provide accurate and helpful information!

  • If you are going to fast, may I suggest that you take vitamin C at least 1,000 mgs and B Vits or Brewers Yeast. Garlic has antiviral properties so chew on that. This will help build immune system up.

  • There has been some suggestion fasting is one way we can tackle the virus when we have it, starve a fever feed a cold, while also boosting our immunity and Defences against it. Could you comment on this a little more specifically please?

    • If fasting consumes cancerous free-radicals, is as effective (if not more) as stem-cell-treatment, and disposes (with expedience) toxins, perhaps then viruses can be subdued with it (combined with good consciousness, hygiene, and purity etiquette).
      Ultimately listen to your body and the wisdom within and keep oneself safe.


  • Thank you for the thoughtful video, reminders and suggestions. Will keep those in mind. Stay safe and healthy too doc! 💪🏻

  • I was JUST thinking about this myself, thanks for saving me the effort of looking it up myself! Excellent work and public service, stay healthy!

  • Thanks for this article and video.
    What would you advise to those of us who, working from home while having extra full kitchen, tend to visit the kitchen for snacks all the time?
    I feel an urge to eat, I suppose due to the overal stress. Even though rationally there’s no reason for it. These days I just look for something to chew all the time. Mainly for sweet or very salty stuff like cookies or Salted nuts.
    Especially during the lockdown (in my country) I don’t need even half of my regular intake, instead I eat twice as much.
    I suspect my body is sort of ‘getting ready for the hard times’, which I’m very unhappy with.
    Could you give an advise how to deal with it?
    Thank you

    • Most likely hormonal stimulation via nervous perceptory intake. What you REALLY crave is likely to be the poison and what you have mild craving for now and then is likely to be the medicine.

      Listen to the inner wisdom and stay safe.

  • I would say fasting has become more important because of the the coronavirus. As we know our immune system is our first and because of this virus our only line of protection. However because of our modern life style our immune system has been, to say the least, corrupted.
    It needs a detox program. We need one or two short time window each day (60) were we can eat foods high in Vitamins D3 – E-B – C etc along with essentials minerals Zinc, Magnesium etc. But first refined sugars and other additives stored in our gut needs to be cleared from the body. For example one litre bottle of a high carb drink can cut down our vitamin C supply almost by half. This and all the high carb junk we have been eating needs to go. We also need sleep plans to replace our white blood cell. This fasting program has arrived just in time.

  • Great video and information! Thank you for all that you are doing to keep us safe and bettering our lives!

  • Thank you for this information!
    Quick question tho, as this is my first time on a Fasting Regiment, but Wouldn’t fasting actually strengthen the immune system?

  • Hello, any recommendations on fasting as I am post partum 10 weeks with no fasting experience. I am exclusively breast feeding and do not want to disturb my milk production. With that and almost any parent can attest too, I am very sleep deprived as well so would not want to compromise immune system more. Recommendations are welcomed! Thanks

    • Mothers who are feeding the offspring need iodine more than the rest of us (most folks are deficient in it). Get some quality stuff which is in a consumable format. (not alcohol based).

  • I’m on day 28 on the 16:8 and very pleased with results.. walking 2-3 miles a day. I’m reading the messages about lowering of your immune system during this time. Is it recommended not to do the 16:8 everyday?

  • Hello, thanks so much for this information. What are your views on multi day caloric restriction / FMD? Would this have the same impact in terms of cortisol as a multi day fast? Thanks very much.

  • Thank you Doctor for the info. I have been doing Zero fasting since September and never felt better. I do 18-19 hour fast everyday and have lost 60 pounds, and for the first time in my adult life have control over what and when I eat. I feel amazing, and will continue this lifestyle change all my life! Thank you, thank you!

  • Thank you so much for clarifying! I did a long fast before it got crazy and then I just wasn’t sure what to do. We are being careful to eat as well as possible, get outside and be active as we can. Thank you!

  • Thank you so much for sharing. 🙂 I just finished a 20/4 and was grateful you said 2 days and beyond, which I’ve never done.

  • Would you please, please share bibliography on this?

    Given the fact that infected people are dying from an overreaction of the immune system, wouldn’t it make sense to fast to diminish the immune system if you already have the virus?

  • Thank you so much! I could listen to him all day. Very informative and very realistic. He may be a Doctor but he’s also very real about daily life and human behavior, good or not so good. People will be more likely to listen to someone like this! So blessed to have him in our Zero community! #realtalk from a #realguy #luvit #Thankyou

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