The Impact of a Vegan Diet on Aging A recent study investigated the effects of switching to a vegan diet in twins, finding that even short-term dietary changes appeared to alter biological markers of aging. This observational study raises intriguing questions about how diet influences biological age, including the short-term and long-term effects of adopting a vegan diet, and whether the exclusion of meat or calorie reduction plays a more significant role. The study, which was relatively small, involved 21 pairs of twins. One twin from each pair followed a vegan diet while the other continued with an omnivorous diet that included meat for two months. The researchers focused on changes in DNA methylation levels, which is a process that epigenetically alters gene expression. Generally, increased DNA methylation is seen as a marker of aging. Blood samples were collected from the participants at the beginning and end of the eight-week period to analyze DNA methylation changes. The results showed that twins on the vegan diet experienced a reduction in biological age and aging markers related to heart, hormone, liver, and inflammatory and metabolic systems. These changes were not observed in the twins who followed an omnivorous diet. Since this was an observational study, the researchers cannot definitively conclude that the vegan diet caused the changes in biological age. Another potential factor could be weight loss, as those on the vegan diet lost an average of two kilograms during the study. While it is notable that a reduction in biological age was observed over a short period, the study's duration did not allow for the assessment of long-term dietary effects. Tom Sanders, Professor Emeritus of Nutrition and Dietetics at King's College London, pointed out potential risks of a long-term vegan diet without vitamin B12 supplementation, which can lead to nervous system damage. He also noted that long-term studies on vegans indicate adverse effects on bone density due to low calcium and marginal protein intake. Sanders mentioned that while vegan diets might have positive health effects in middle age, such as lower risks of cardiovascular disease and type 2 diabetes, older vegans might face issues like muscle loss, low bone density, and neurological disorders that impact their quality of life. He also stated that life expectancy does not differ between vegans and those who follow mixed diets. Moreover, altering DNA methylation does not necessarily guarantee a longer life. For insights into longevity, one might consider the lifestyles of people in the Blue Zones. The study was published in BMC Medicine.
