According to new research led by the USC Leonard Davis School of Gerontology, diet cycles that mimic fasting can reduce the aging of the immune system as well as insulin resistance and fatty liver. As a result, biological lifespan is shortened.

The study, which appears Feb. 20 in Nature Communications, adds to the body of evidence supporting the beneficial effects of a fasting-mimicking diet (FMD).

The FMD is a five-day diet that is high in unsaturated fat and low in total calories, protein, and carbohydrates and is designed to mimic the effects of a water-only fast while still It provides essential nutrients and is very easy for people to complete. fast. The diet was developed by the laboratory of USC Leonard Davis School Professor Walter Longo, senior author of the new study.

“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, compared to aging and disease risk factors. Based on modifications and a validated method developed by Levine. Group to estimate biological age,” Longo said.

Previous research led by Longo has indicated that short, frequent FMD cycles are associated with a range of beneficial effects. They can:

  • Promote stem cell regeneration.
  • Reduce the side effects of chemotherapy.
  • Reduce dementia symptoms in mice.

In addition, FMD cycles may reduce risk factors for cancer, diabetes, heart disease and other age-related diseases in humans.

The Longo lab also previously showed that one or two cycles of FMD five days per month increased the health and lifespan of mice fed either a normal or Western diet, but the effects of FMD on lifespan and biological lifespan, Liver fat, and the aging of the immune system in humans was unknown until now.

Less risks of disease and more youthful cells

The study analyzed the effects of the dose in two clinical trial populations, each with men and women between the ages of 18 and 70. Patients who were randomized to a fasting-mimicking diet went through 3-4 monthly cycles following FMD for 5 days, then ate a normal diet for 25 days.

FMD consists of plant-based soups, energy bars, energy drinks, chip snacks, and teas distributed over 5 days, as well as a supplement that provides high levels of minerals, vitamins, and essential fatty acids. . Patients in the control groups were instructed to eat either a normal or a Mediterranean-style diet.

Analysis of blood samples from trial participants showed that patients in the FMD group had lower risk factors for diabetes, including insulin resistance and lower HbA1c results. Magnetic resonance imaging revealed a reduction in abdominal fat as well as fat within the liver, improvements associated with a lower risk of metabolic syndrome. In addition, FMD cycles appear to increase the lymphoid-to-myeloid ratio—an indication of a more youthful immune system.

Further statistical analysis of the results of both clinical studies showed that FMD participants shortened their biological lifespan — a measure of how well one’s cells and tissues are functioning. As opposed to chronological age — an average of 2.5 years.

“This study shows for the first time from two different clinical trials evidence of reduced biological aging, along with evidence of restoration of metabolic and immune function,” Longo said.

The study, conducted by first authors Sebastian Brandhorst, research associate professor at USC Leonard Davis, and Morgan E. Levine, founding principal investigator of Altos Labs and USC Leonard Davis PhD alumna, is a short Provides further support to FMD capability as the duration of the period. Achievable dietary interventions that can help people reduce their disease risk and improve their health without extensive lifestyle changes, Longo said.

“Although many physicians are already recommending FMD in the United States and Europe, these findings should encourage many health care professionals to recommend FMD cycles to patients with have higher than desirable levels of disease risk factors as well as the general population of interest. increased function and younger age,” Longo said.