Valter Longo presented a five-day fasting-mimicking diet as a potential intervention to extend longevity and combat age-related disease during the 21st annual Stare-Hegsted Lecture on Nov. 9.
Speaking at the Harvard T.H. Chan School of Public Health, the Edna Jones Professor in Biological Sciences and Gerontology at the USC Leonard Davis School of Gerontology detailed how the program, developed by researchers at the University of Southern California, influences nutrient-sensing pathways to trigger cellular benefits.
The fasting-mimicking diet (FMD) provides a low-calorie, plant-based regimen high in healthy fats but restricted in sugar and protein. Longo said the cycle triggers specific biological responses, including stem cell activation, cellular reprogramming, and autophagy, which acts as a cellular recycling system. By maintaining low protein and sugar levels, the program suppresses nutrient-sensing pathways the lab identified as key drivers of aging and age-related disease.
The program is currently sold in commercial kits containing pre-portioned soups, snacks, and supplements. Because the formulation is based on specialized research, the company behind the kits notes that it is difficult for individuals to safely replicate the specific nutrient ratios on their own. Longo consults for the company that produces these kits but donates his fees to charity.
Longo’s team has evaluated the effects of five-day FMD cycles across more than 40 clinical trials. Participants showed reduced body weight and abdominal fat without losing lean muscle mass. In pre-diabetic patients, the cycles appeared to restore normal glucose levels.
According to the Harvard T.H. Chan School of Public Health, other reported outcomes included a reduction in biological age by approximately 2.5 years based on specific blood markers. The study findings also highlighted beneficial effects related to Crohn’s disease markers, chronic kidney disease damage markers, and the effectiveness of chemotherapy and hormone therapy in cancer patients.
Longo emphasized that the diet is intended as a complement to existing medical treatments rather than a replacement. The research team is now investigating the diet’s potential as a preventive intervention for individuals at high genetic risk for Alzheimer’s disease.
Longo stated he hopes the program will become more integrated into clinical practice as a tool for physicians to manage age-related health risks. While the diet is designed to avoid the health risks associated with water-only fasting, it is intended to be used under clinical guidance.
Longo presents the diet as a medical tool rather than a standard lifestyle change, suggesting it should be incorporated into a doctor’s therapeutic toolkit.
This approach builds on research into nutrient-sensing pathways, which have been studied as key drivers of aging and age-related disease.