A pilot clinical trial led by researchers at Cedars‑Sinai Medical Center and UT Health San Antonio, in collaboration with L‑Nutra, Inc., found that a 5‑day fasting mimicking diet (FMD) was associated with enhanced autophagy‑related cellular activity and significant metabolic health improvements in healthy adults. This study is reported as the first human trial to directly measure autophagic flux during a dietary intervention, offering new insights into how nutrition‑based regimens can influence fundamental cellular repair mechanisms.
In the randomized controlled study, 30 healthy participants were assigned to one of two FMD formulations (including Prolon) or a continuing normal diet. Blood samples taken before, during and after the 5‑day period showed that individuals on the Prolon FMD had measurable increases in autophagy flux — a biomarker reflecting the rate and efficiency of the body’s cellular “clean‑up” and recycling process. Both FMD groups also demonstrated significant improvements in weight, fasting glucose, insulin sensitivity and ketone levels compared with the control group.
Autophagy, a natural process through which cells break down and recycle damaged components, plays a key role in cellular repair, energy balance and healthy aging. Its relevance to human health was recognised with the 2016 Nobel Prize in Physiology or Medicine, but direct evidence of dietary modulation in humans has been limited until now. The FMD is designed to deliver essential nutrients while triggering many physiological effects of fasting without complete food abstinence.
Researchers behind the study said the findings suggest that controlled, periodic fasting‑mimicking nutrition could offer a safe, non‑pharmaceutical way to activate beneficial autophagic pathways and support metabolic health—potentially opening new avenues for interventions targeting aging, cardiometabolic risk and disease prevention.
