Valter Longo
Biogerontologist at USC, inventor of the fasting-mimicking diet
Valter Longo is a professor of gerontology and biological sciences at the University of Southern California, where he directs the Longevity Institute. He studies how fasting and nutrition affect aging and disease, developed the fasting-mimicking diet, and founded L-Nutra, which sells it as ProLon. He wrote The Longevity Diet and donates his book proceeds to research foundations.
Updated November 1, 2026 · 1 experiment · cited in 5 guides
What Valter Longo has tried
1 experiment we can source: 1 kept. Trying something is not recommending it; each entry says which.
Kept
Fasting-mimicking dietDiets and fasting
Dates not stated · Recommends it to others
Follows the fasting-mimicking diet he developed, along with a 12-hour daily eating window, and recommends both to his patients; he founded L-Nutra, which sells it as ProLon.
“I do everything that I preach.”
CNBC Make It, Italian longevity expert's 4 daily habits for a long, healthy life (July 2025) · Status checked July 23, 2025 · Suggest a correction
Where our guides cite Valter Longo
Their public positions, summarized in our words. Follow each link for the full context.
Calorie restrictionOppose or doubt it
Argues that chronic severe restriction is too hard to sustain, described Roy Walford's regimen as brutal, and promotes periodic fasting-mimicking cycles instead, which his company sells.
Fasting-mimicking dietSupport it
Developed the FMD from his fasting research and founded L-Nutra in 2009 to sell it as ProLon; argues periodic cycles lower disease risk markers and biological age, and says he donates his L-Nutra consulting fees and book royalties to charity.
High-protein dietOppose or doubt it
Senior author of a cohort study linking high protein at ages 50 to 65 to higher IGF-1, cancer and overall mortality; suggests low protein in midlife and moderate to high protein after 65.
Low protein intake, IGF-1, cancer and mortality (Cell Metabolism, 2014)
Intermittent fastingMixed or cautious
Favors keeping daily eating within 12 hours or less and eating two meals a day for people prone to weight gain, but prefers simple, flexible rules over strict long daily fasts.
FoundMyFitness, Dr. Valter Longo's personal approach to fasting
Water fasting and extended fastingMixed or cautious
Studies the regenerative effects of prolonged fasting, but developed a fasting-mimicking diet partly because most cancer patients would not do water-only fasts; he has a commercial interest in that alternative.