The Secret Power of Fasting for Longevity and Healing | Dr. Valter Longo

These days, we hear a lot about fasting. Intermittent fasting, time-restricted eating, and water fasting are just some of the many terms being thrown around in support of better health. And we can’t forget about the high-fat, ketogenic, and low-carb approaches that are gaining in popularity as well. Which one is best? What does it all mean for our longevity, brain health, and overall wellness? My guest on this week’s episode of The Doctor’s Farmacy is here to sift through the terminology and confusion around fasting.

Dr. Valter Longo is internationally recognized as a leader in the field of aging studies and related diseases. Known as a “Guru of Longevity,” Dr. Longo is currently Professor of Biogerontology and Biological Sciences and Director of the Institute of Longevity of the School of Gerontology at the University of Southern California in Los Angeles, as well as Director of the Oncology and Longevity Program at IFOM in Milan. He is also the Scientific Director of the Create Cures Foundation and the Valter Longo Foundation. Valter is the author of an extraordinary new book, The Longevity Diet. The culmination of 25 years of research on aging, nutrition, and disease across the globe, it provides an easy-to-understand, accessible and implementable road map to living well longer through improved nutrition.


Dr. Hyman is an 11-time New York Times bestselling author, family physician and international leader in the field of Functional Medicine. His podcast, The Doctor's Farmacy, is a place for deep conversations about the critical issues of our time in the space of health, wellness, food and politics. New episodes are released every Wednesday here on YouTube, and wherever you listen to podcasts.

Find him and more of his content all over social media:


Dave McKinnon

  • Anne Henderson says:

    Thank you to Dr. Longo and Dr. Hyman. This is amazing information. I will continue to work on finding my individual solution, but what a great roadmap. This is a must watch conversation!

  • Melis says:

    Read the book, tried the fmd and Highly recommend it! Its not risky, like a water fast and it got me thinking more about the macro ratios and certainly got me eating healthier than I already eat. Love it, keep up the brilliant work gentlemen!

  • MISSIONCAT11 says:

    Dr. Longo is the man who discovered that fasting, before receiving chemotherapy, protected mice from the harmful side-effects of chemotherapy. Further, the fasting mice did not lose their hair or get sick, and none of them died due to the large doses of chemotherapy they received. Human volunteers have had similar results.

    • Veggiegirl says:

      I think he should win the Noble Prize for this! Incredible!!!

    • Zohar Elyada says:

      and still he says cancer patients resent the recommendation to fast…? go figure.

    • Me me00 says:

      This is so encouraging. I’m about to have a massive amount of Chemo in 4 weeks time to prepare for a bone marrow transplant. I am not liking the idea of all the potent toxic chemicals I will have to endure, but I’ll be fasting before and through it. It will be an interesting experiment to see what actually happens and if I feel better, less side effects.

    • HakunaMatata says:

      @Me me00 Good luck. Please keep us posted.

    • Believe N See says:

      @Me me00 Prayers and best wishes to you. 💜

  • Michael Scally says:

    I saw Valter Longo on the BBC documentary “Eat, Fast & Live Longer” with Michael Mosley five years ago and I was compelled to follow the 2/5 diet along with exercise and the results were amazing. In seven months I had lost 40 Lbs along with the Diabetes type 2 and improved cognitive ability. Now, after five years of sedentary life (no fasting nor exercise) I’ve gained everything back (the 40 lbs + diabetes type 2), but feeling much worst than before. So I’ve started the fasting again and limited exercise due to my knee pain, so I will see what happens

    • wim lammens says:

      thanks for sharing so we can avoid the same results. keep up the good work, inflammation is food related, cut out sugars in drinks, alcohol and any processed food and you will be able to enjoy yr old age in stead of being miserable, depressed and fat waiting for death as a relieve.

    • Pat Minthorn says:

      You can do it

    • samjarea says:

      How’re you getting?

    • Michael Scally says:

      @samjarea I stopped fasting a few years ago. Now at 67, everything gets harder. I want to start fasting again, but it is much harder

    • samjarea says:

      @Michael Scally Thanks for getting back me. Maybe start slowly and build it up. All the best.

  • Karen Watanabe says:

    Feeling blessed to have listened to this interview. Thank you both.

  • Brian Booth says:

    I have done my own version of the fast mimicking diet about 16 times over three or 4 years and I have found exactly what Professor Longo cites. The most noticeable effect because I have never suffered from any kind of illness(have been living healthy for 40years) is that my lung function increases. I go running, cycling or resistance training and I perform as I did 10 or more years ago.

    • Fajar Hamzah Azhari says:

      Yes same as me. I felt that my body energy increased significantly since i started dry fasting. Now i can go swimming for long time without getting fatigue. And can sleep easily than before the diet.

    • Scottlp2 says:

      FajarID Fasting I get, but Dry? What convinced you to do dry ie fasting without drinking water (if I understand the term). Thanks.

    • Ritalie says:

      @Scottlp2 Dry fasting forces the fat to be converted into water. The fat in our body can actually be dissolved and turned into water, and this means, all the stored toxins in the fat, including pesticides, heavy metals, halides like bromine, drugs, are released from the body. Sweating, and dry fasting, both force toxins out of the fat cells. When you sweat a lot without drinking water, the body will begin releasing stored liquid reserves, along with all the toxins. Not drinking water is very important for short term detoxing. For long term fasting, it’s obviously not practical. Sauna use, sweating, and dry fasting, can be combined for rapid detoxing. This is covered in a book called “Clear Body Clear Mind.” Niacin (not fake niacin) dramatically accelerates the release of the toxins in the fat cells, which is why it causes flushing. The flushing goes away over time.

    • Michelle Hashish says:

      @Ritalie how long is a healthy dry fast?
      You advise a dry fast is healthy if it’s short term – is that one day only?

    • Rui Barreiras says:

      Does anyone know the link between a 16:8 fast and gallstones formation?

  • Seabound says:

    I admire Hymans openess and willingness to adopt to new information. Not many can do that. It definately increases my willingness to listen to his advise. Its not about politics and ego, its a search for truth.

  • brian warner says:

    I have followed Longo since his work on mice with E.A.E in 2016 amazed me. At first, I had many credibility concerns about his FMD. I have spent countless hours studying his work on fasting, as well as Keto strategies and can now state I believe he is an extraordinary genius and long term (5-7 days) fasting(either Prolon FMD or a variation) is an extremely powerful healing modality, particularly for all things immune system related. In addition, it is wonderful for reducing risks of most common diseases. I have done five FMD’s including a few small adjustments (somewhat less calories and less carbs as a % of calories, with terrific results! Thanks for the interview.

    • Richard Haliburton says:

      Could you enlighten me on choice of diet during your FMD I’m new to this thanks

    • brian warner says:

      @Richard Haliburton I allow myself 600 calories daily. Most importantly, only 10% or so can be protein in order to maximize “autophagy”. Otherwise, minimal sugar and roughly 45% carbs and 45% healthy fats.
      Lower carb fruits(berries), simple soups (vegetable) and avocado is what I usually eat. Hope this helps.

  • Nathan Ichor says:

    What an awesome presentation by Dr Valter Longo. Some of his ideas look more natural to me than all the ketos/paleo/ high fats/low carbs.

  • Isabel Beagle says:

    I have recently started fasting. I did a 3 day fast and now I’ve moved to fasting 3 days a week: Monday, Wednesday & Friday. I’ve been doing this poor to cop for less than a month & have noticed a massive difference. I sleep better, look better, feel better sugar cravings gone. Not hungry ever. I have lost weight & fat. Looking at 1/2 lbs of fat per 24 hour cycle. And when I do eat, I don’t limit my carbs. I think I will be doing this for life. highly recommend fasting, include electrolytes if you’re going to do water fast only.

  • Liz and Skatz says:

    ↖️ Thank you! This is great content and has reaffirmed our journey of keto and IF and how it’s helped us to lose 100lbs and cure my husbands type 2 diabetes 💕

  • CHANNEL AA says:

    This is by far the best Prof. Longo interview I watched on YouTube. Thanks Dr. Hyman.

  • Nicolas Padron says:

    As a medical student, I got essentially no nutritional training. Now I have learned how important nutrition is.

  • Naomi Njeri says:

    I’m so impressed with Dr. Hyman! I hardly see such humble, down-to-earth and open minded people. You are so intelligent and brilliant. Best of luck and live long ❤

  • John C. says:

    Dr. Longo, whether you realize it or not you have dedicated your life to serving humankind. Thank you, from the bottom of my heart for what you are doing. Sincerely, John

  • Lisa Riachi says:

    This was the best interview! Thank you both for the information. It’s unacceptable the lack of funding to encourage proper nutrition. So true that dietary habits influence disease which keeps people on their meds!

    • Omad Outlaw says:

      🤠We are living in the wild west of nutrional science. Nutrion has been more or less just a tool for government and the now the food industries just to sell s**t they call food! Almost everything we eat causes some kind of stress on our bodies and fasting is the best way to balance out the stress and help us live longer! Fasting mimicking is the next best thing and there are a lot of different ways to do a fasting mimicking diet. Do your own research and pick what fits you go for it!🤠

  • Linzy NHS says:

    Am a NHS nurse and have worked with cancer patients and can say, without a doubt, that no doctor or otherwise talks about the importance of healing foods, what to eat or fasting. You see the medics are in kahoots with the drug companies. Am hoping in my lifetime I will see the importance of what Valter longo is talking about will come true in the cancer centre where I’ve worked.

    • motomyrtle says:

      I hope you do. My brother has throat cancer and I told him to cut out sugar and fast before and after radiation. His oncologist told him they had free Boost drinks at the treatment center and he should take one with him wherever he goes and drink whenever he could get anything down. 😢 🤯 and if he can’t get enough food and liquids down, they’re going to put in a feeding tube. 🤬

    • Anne McCarron says:

      People who want to be healthy have got to do their own research and be discerning about what’s correct & what is not.

    • Ana Thompson says:

      @motormirtle You should send him this podcast so he can learn the truth.

  • Ben Cattabriga says:

    Mark is so a down to earth, he has a great sense of humor and he’s brilliant!!! He should have MILLIONS of subscribers!!!

  • Coco says:

    I’m into my 36 hours fasting and 12 more hours to go! I’m feeling awesome, happy, and energetic 🎉🎉🎉

  • Katarina Hinsey says:

    This will be my new protocol and may well save my life as i am in the trenches with cancer. Thank you Dr. Hyman and thank you Dr. Longo.

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