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✅ Introduction to episode 24 with Dr. Valter Longo. ✅ How calorie restriction shaped modern longevity science. ✅ Detailed show notes.  ✅ The origins and mechanisms of the Fasting-Mimicking Diet. ✅ The dangers of high-protein and ketogenic diets.

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Few have shaped my thinking around diet and fasting like Valter Longo

Our latest guest on the LEVITY podcast is none other than Dr. Valter Longo - one of the most influential scientists in the field of aging and nutrition.

There are two reasons why I featured Longo so prominently in my book Evigt Ung - Min och Människans Dröm om Odödligheten (2022).

First, if you had to name a single scientific thread running through the history of longevity research, calorie restriction is hard to beat. And few have done more to modernize and translate that insight into real-world practice than Longo.

Second, I hold Valter Longo in the highest regard. I've tried his Fasting-Mimicking Diet (FMD), I’ve followed his work on The Longevity Diet, and I find his scientific contributions both rigorous and unusually translational. He doesn’t just publish papers - he builds systems, tests interventions in clinical trials, and tries to implement science into healthcare.

In this conversation, we cover the science, history, and application of fasting, nutrition, and longevity - including new work on cancer, metabolism, and organ regeneration. We also discuss the philosophical and political obstacles that stand in the way of real change.

What you'll learn in this episode:

✅ The story of Longo’s early music career - and why he left it to study aging.

✅ How calorie restriction shaped modern longevity science.

✅ Why Biosphere 2 and Roy Walford's work was both inspiring and cautionary.

✅ The origins and mechanisms of the Fasting-Mimicking Diet.

✅ What Longo learned about autophagy, stem cells, and organ regeneration.

✅ Why protein intake before and after age 65 should be treated differently.

✅ What the media and doctors get wrong about obesity, food, and metabolism.

✅ The dangers of high-protein and ketogenic diets.

✅ Why Longo is deeply skeptical of TRT, growth hormone, and biohacking shortcuts.

✅ How fasting can enhance cancer treatment - and why Longo wrote his new book Fasting Cancer.

✅ Why we need a new kind of “digital school” for lifestyle medicine.

You can watch the episode below or listen to it on Spotify, Apple Podcasts or other places, like PocketCasts. Please follow, like and subscribe! 🙏🏼 This will boost our chances of reaching a bigger audience.

A detailed overview of the episode

Welcome & personal update

• Peter introduces Dr. Valter Longo, Edna Jones Professor of Gerontology and Biological Sciences and Director of the Longevity Institute at the University of Southern California, Leonard Davis School of Gerontology, Los Angeles.

• Peter and Patrick congratulates Valter on the birth of his son, Adriano.

• Peter asks why Valter is in Italy; Valter explains the family visit and newborn.

From jazz guitarist to aging biochemist

• Valter recounts wanting to be a professional musician, studying jazz at the University of North Texas, and forming the rock band DOT (Department of Transportation) in Los Angeles.

  • Quote: “Originally I was a musician… I wanted to be a famous one.”

• Professors at UCLA advised him to choose between science and music, prompting the switch.

• Musical influences: Alice in Chains, Stone Temple Pilots, U2, Pink Floyd.

• Might upload DOT’s album during a future foundation fundraiser.

Longevity myths of Sardinia and Calabria

• Valter explains that Sardinia and Calabria are not uniformly “Blue Zones”; longevity is clustered in certain small villages with genetics plus old-style lifestyle.

  • Quote: “The story was presented in the wrong way, like, you know, ‘Sardinia and Calabria and other areas are record longevity zones’. Well, they're not, right. They're not. They just happen to have lot of small villages and they have just amazing longevity”.

• Rising childhood obesity and ultra-processed food threaten Italian life expectancy.

The childhood shock that set his research path

• Valter saw his grandfather die at 70; later learned about Salvatore Caruso who lived to 110 despite similar lifestyle, sparking questions about aging.

• Upon moving to Chicago he watched relatives develop severe diabetes, linking diet to disease.

• Switched major in year two to biochemistry “to study aging more than jazz.”

• Drove 30 miles daily to work in Robert Gracy’s lab.

Roy Walford, Biosphere 2, and the calorie-restriction wake-up call

• Valter joins Roy Walford’s lab while Walford is inside Biosphere 2.

• Peter describes the emaciated crew surviving on ~1 800 kcal/day.

• Valter concludes lifelong severe calorie restriction is impractical and risky; seeks safer molecular pathways.

• References: Walford’s book Maximum Life Span; Weindruch’s rhesus-monkey CR paper.

Cracking longevity pathways in yeast

• Back at UCLA biochemistry, Valter screens yeast mutants and discovers the RAS/PKA and Sch9/mTOR-S6 kinase pathways regulate lifespan.

• Publishes “Regulation of Longevity and Stress Resistance by Sch9 in Yeast” (Science, 2001) after years of rejections.

Birth of the Fasting-Mimicking Diet (FMD)

• Observes that starvation shields normal cells and sensitises cancer cells.

• Early water-only fasting trial with chemo had poor compliance, so NIH backs development of a five-day plant-based FMD (800–1 100 kcal/day).

• Explains the 5-day window: autophagy onset, organ “shrinking and re-expansion,” yet avoids long-term thrifty-metabolism slowdown.

Autophagy, stem cells, and organ regeneration

• Quote: “But autophagy, we think it's just a small part of this regenerative effect. The big part is stem cell and reprogramming, right? So the cell is essentially turning out all these developmental genes and say, okay, we're going to rebuild whatever is being, when it was damaged.”

• Rat study plus first 13 human kidney patients: three FMD cycles reduce proteinuria and triple circulating kidney progenitor cells.

Protein wars and the Five-Pillar test

• Rebuts Peter Attia’s 2 g/kg protein target.

  • Quote: “Protein is the worst thing - high protein, animal proteins - the worst thing you can do.”

• Five pillars he cross-checks: epidemiology, centenarians, clinical trials, basic biology, complex-systems analogy.

• Recommendation: 0.8 g/kg until 65, about 1 g/kg after 65, focus on plant sources.

• Labels red meat “enemy number one or two” and calls ketogenic diets hazardous for longevity.

Obesity, GLP-1 drugs, and the “un-conspired conspiracy”

• Argues food, pharma, hospitals, and even professors profit from obesity status quo.

  • Quote: “It’s like who’s in charge? Why don’t they get fired?”

• Warns that GLP-1 agonists without lifestyle change lead to muscle loss, depression, and other adverse signals.

• Calls for a reimbursed multidisciplinary “digital school” of lifestyle medicine.

Growth hormone, TRT, and biohacking skepticism

• Cites Ecuadorian Laron-syndrome dwarfs as proof low IGF-1 protects against cancer and diabetes.

• Testosterone or growth-hormone replacement, according to Valter, should be last-line after exhaustive lifestyle diagnostics.

Cancer + fasting and the new book Fasting Cancer

• More than 20 clinical trials of FMD with chemotherapy underway.

• Italian 100-patient study found five stage-IV exceptional responders.

• Book, Fasting Cancer, written to give oncologists and patients a vetted protocol and discourage improvisation.

• Notes mouse data where alternate-day fasting with doxorubicin increases cardiotoxicity - timing matters.

Implementation goals and healthcare reform

• Valter seeks government reimbursement schemes in the US and Italy to scale lifestyle-medicine protocols.

• USC program now trains registered dietitians in FMD and Longevity Diet counseling.

Genetics of longevity — FOXO variant

• Peter mentions carrying the FOXO3 rs2764264 C allele; Valter explains it likely boosts constitutive protection.

  • Quote: “That could be a calorie-restriction-like response that continues.”

Recommended reading from Valter

• Luigi Pirandello – One, No One and One Hundred Thousand.

• T. Colin Campbell – The China Study.

• Jon Fosse – Morning and Evening.