A recent study investigated the effects of an eight-week vegan diet compared to an omnivorous diet on biological age estimations, which reflect overall health and the risk of age-related diseases like heart disease and Alzheimer’s.
Researchers assessed biological age by measuring DNA methylation levels—epigenetic changes that influence gene expression without altering the DNA sequence.
Previous studies have linked higher DNA methylation levels to aging. The results of this study align with earlier evidence suggesting that plant-based diets may have anti-aging benefits. However, the study’s lead authors and external experts advise caution in interpreting these findings due to the small sample size and limited duration.
Published in BMC Medicine and highlighted in Netflix’s docuseries “You Are What You Eat: A Twin Experiment” (2024), the findings encourage further exploration of how diet and lifestyle choices impact health at a genetic level. Researchers at the Stanford Prevention Research Center and TruDiagnostic, a leading lab in epigenetic testing and research, aimed to determine how a vegan diet affects human biological age and health compared to an omnivorous diet.
Initially, 22 generally healthy adult identical twin pairs were recruited from the Stanford Twin Registry and other sources. One twin pair was later removed for not adhering to study conditions, resulting in 21 twin pairs (42 individuals) for the final analysis.
The participants were predominantly women (77%), with an average age of 40 and an average body mass index (BMI) of 26.
After baseline assessments, one twin from each pair was randomly assigned to follow either a healthy plant-based vegan diet or a healthy omnivorous diet for eight weeks. The study comprised two four-week phases: the first with meals provided by Trifecta Nutrition tailored to their diet, and the second with self-prepared meals guided by health educators.
The omnivorous group was given daily targets for consuming animal products, such as meat, eggs, and dairy, while the vegan group completely avoided all animal products.
Researchers monitored dietary habits through unannounced 24-hour recalls and participant food logs, ensuring data quality with interviews conducted by registered dietitians.
The study assessed how diet influences blood DNA methylation and epigenetic aging across various organ systems. Using advanced analytical methods at TruDiagnostic, the researchers identified diet-specific changes in clinical, metabolic, and protein markers.
The twin-pair study design, which accounted for genetic, age, and sex differences, underscored the substantial dietary impact on DNA methylation changes. Notably, participants who followed a vegan diet for eight weeks exhibited a reduction in the biological age of five organ systems: heart, hormonal, liver, inflammatory, and metabolic systems.
Researchers also identified positive changes in biomarkers, such as a reduction in C-reactive protein levels among the vegan group, suggesting a potential decrease in systemic inflammation.
Participants on an omnivorous diet experienced changes in key metabolic markers as well, including an increase in tryptophan levels—an amino acid prevalent in animal proteins—that can boost serotonin levels and potentially influence mood regulation.
As reported by aol.com, overall, the study demonstrated distinct DNA methylation changes linked to each diet, with the vegan diet uniquely producing beneficial methylation changes that may contribute to a decrease in biological age.