TOPLINE:
METHODOLOGY:
- In two clinical trials, monthly 5-day cycles of an FMD (a proprietary line of plant-based, low-calorie, and low-protein food products) showed lower body weight, body fat, and blood pressure at 3 months.
- Researchers assessed secondary outcomes for the impact of the diet on risk factors for metabolic syndrome and biomarkers associated with aging and age-related diseases.
- This study looked at data from nearly half of the original 184 participants (aged 18-70 years) from the two clinical trials who went through three to four monthly cycles, adhering to 5 days of an FMD in either a crossover design compared with a normal diet or an intervention group compared with people following a Mediterranean diet.
- Abdominal fat and hepatic fat were measured using an MRI in a subset of representative participants. The study also assessed metabolic blood markers and lipids and lymphoid-to-myeloid ratios (for immune aging).
- Biological age estimation was calculated from seven clinical chemistry measures, and life expectancy and mortality risk estimates and a simulation of continued FMD cycles were based on the National Health and Nutrition Examination Survey.
TAKEAWAY:
- In 15 volunteers measured by MRI, the body mass index (P = .0002), total body fat (P = .002), subcutaneous adipose tissue (P = .008), visceral adipose tissue (P = .002), and hepatic fat fraction (P = .049) reduced after the third FMD cycle, with a 50% reduction in liver fat for the five people with hepatic steatosis.
- In 11 participants with prediabetes, insulin resistance (measured by homeostatic model assessment) reduced from 1.473 to 1.209 (P = .046), while A1c levels dropped from 5.8 to 5.43 (P = .032) after the third FMD cycle.
- The lymphoid-to-myeloid ratio improved (P = .005) in all study participants receiving three FMD cycles, indicating an immune aging reversal.
- The estimated median biological age of the 86 participants who completed three FMD cycles in both trials decreased by nearly 2.5 years, independent of weight loss.
IN PRACTICE:
“Together our findings indicate that the FMD is a feasible periodic dietary intervention that reduces disease risk factors and biological age,” the authors wrote.
SOURCE:
The study, led by Sebastian Brandhorst, PhD, Leonard Davis School of Gerontology, University of Southern California (USC), Los Angeles, and Morgan E. Levine, PhD, Department of Pathology, Yale School of Medicine, New Haven, Connecticut, was published in Nature Communications.
LIMITATIONS:
The study estimated the effects of monthly FMD cycles based on results from two clinical trials and included a small subset of trial volunteers. By study measures, the cohort was healthier and biologically younger than average people of similar chronological age. Of the 86 participants, 24 who underwent FMD cycles exhibited increased biological age. The simulation did not consider compliance, dropout, mortality, or the bias that may arise owing to enthusiastic volunteers. Estimated risk reductions assume an effect of change in biological age, which hasn’t been proven. Projections from extending the effects of FMD to a lifelong intervention may require cautious interpretation.
DISCLOSURES:
The study was supported by the USC Edna Jones chair fund and funds from NIH/NIA and the Yale PEPPER Center. The experimental diet was provided by L-Nutra Inc. Some authors declared an equity interest in L-Nutra, with one author’s equity to be assigned to the nonprofit foundation Create Cures. Others disclosed no conflicts of interest.
A version of this article appeared on Medscape.com.