A small study published in BMC Medicine suggests that following a vegan diet for eight weeks may reduce biological age, as measured by DNA methylation—an epigenetic marker associated with aging.
The study followed 21 pairs of identical twins, with one twin adopting a vegan diet while the other continued an omnivorous diet. After eight weeks, the vegan group showed lower biological age estimates and improvements in several age-related measures involving the heart, liver, metabolic, hormonal, and inflammatory systems. On average, biological age was reduced by approximately 0.63 years.
Researchers believe these changes may reflect slower biological aging, but they caution that participants on the vegan diet also lost more weight than those in the omnivorous group. As a result, it remains unclear whether the observed benefits were due to the diet itself, the weight loss, or a combination of both.