In a recent study, individuals experienced a notable reversal in their biological age by approximately two and a half years on average by adhering to a diet that mimics fasting for five days each month.
The research, led by senior study author Valter Longo from the USC Leonard Davis School of Gerontology, introduced the fasting-mimicking diet (FMD), crafted to replicate the effects of water-only fasting while ensuring essential nutrient intake, according to a press release. Traditional water fasting entails consuming only water for a duration spanning from 24 to 72 hours.
Though fasting may not be suitable for everyone, scientific inquiry, primarily conducted on cellular and animal models, has suggested potential health advantages, including reduced risks of specific cancers, type 2 diabetes, and cardiovascular ailments.
The process of autophagy, wherein the body eliminates aged or damaged cells to make room for new ones, is believed to be triggered by fasting or calorie restriction. This mechanism, crucial in retarding aging, initiates when cells face stress or nutritional deprivation, gradually diminishing with age, as explained by experts at The Cleveland Clinic.
In the study, half of the 100 participants were instructed to follow the FMD for five days monthly over a span of three months, maintaining their regular dietary habits for the remainder of the month. The other half adhered solely to their usual diet. The participants, aged between 18 and 70 and comprising both genders, underwent blood tests and MRI scans.
Findings revealed that individuals in the FMD group exhibited reduced susceptibility to diabetes, along with lower levels of abdominal and liver fat—markers linked to decreased risks of metabolic syndromes like liver disease, cardiovascular conditions, and diabetes, the study disclosed. Moreover, their lymphoid-to-myeloid ratio, indicative of a rejuvenated immune system, experienced enhancement. These parameters served as metrics for assessing biological age, as delineated in the study published on January 20 in Nature Communications.
While chronological age denotes the number of years one has lived, biological age gauges cellular and tissue functionality. Nonetheless, experts remain divided on the precise interpretation of biological age, cautioning that youthful cells do not necessarily equate to superior health, and there exists no definitive standard for cellular appearance at different ages, as previously reported by Business Insider.
Participants partook in a variety of food items during the fasting period, including soups and energy bars, as part of the FMD regimen. Administered by L-Nutra, a nutritional technology company founded by Longo, the diet comprised low-calorie, high unsaturated fat content, with minimal protein and carbohydrate intake. On the initial day of fasting, participants consumed approximately 1,100 calories, followed by around 720 calories on subsequent days, with no specific time restrictions for eating.
Longo emphasized in a press statement, “This is the first study to show that a food-based intervention that does not require chronic dietary or other lifestyle changes can make people biologically younger, based on both changes in risk factors for aging and disease and on a validated method developed by the Levine group to assess biological age.”
Nevertheless, the study’s cohort, comprising mostly healthier individuals compared to the general U.S. population, underscores a limitation in generalizing the results to broader demographics, cautioned the authors.
Professor Clare Bryant, specializing in innate immunity at Cambridge University, UK, and unaffiliated with the study, remarked to Business Insider, “It would need to be rolled out to lots more people in different demographic and health groups to really understand how beneficial fasting is for everyone.”
Past research has associated the FMD with stem cell regeneration and mitigating chemotherapy side effects in rodent studies.
David Clancy, a lecturer exploring aging biology at Lancaster University, UK, who was not involved in the research, expressed optimism regarding potential benefits of the regimen, estimating a potential increase in healthy life expectancy by three to four years during ages 40 to 60, particularly for individuals with elevated BMI, blood pressure, or blood sugar levels.
However, Clancy cautioned about the stringency of the diet, suggesting adjustments to facilitate adherence, such as scheduling the latter fasting days on weekends.
He also proposed the cultivation of a consistent exercise routine as an alternative means to achieve comparable or superior results, asserting its sustainability into older adulthood.