A Stanford University study indicates that an eight-week vegan diet may reduce biological age, evidenced by decreased DNA methylation levels, which are markers of aging. The study involved 21 pairs of identical twins, with one twin adopting a plant-based diet while the other maintained an omnivorous diet. Vegans experienced lower biological ages in various body systems and lost more weight, potentially due to consuming fewer calories. However, experts caution that the study's short duration and potential for nutritional deficiencies, such as vitamin B12 and calcium, in long-term vegan diets could pose health risks. The study's findings were published in BMC Medicine, but further research is needed to confirm long-term impacts. Critics also note that the observed benefits might be primarily due to weight loss rather than the vegan diet itself.