Short-term vegan diet associated with lower biological age estimates 

 An eight-week vegan diet  is associated with lower biological age estimates based on levels of DNA methylation, a type of chemical modification of DNA (known as an epigenetic modification) that alters gene expression but not the DNA itself. 

 Previous studies have shown that increased levels of DNA methylation  are associated with aging. The new findings were published in the journal BMC Medicine, based on a small randomized controlled trial of 21  adult identical twin pairs. 

Varun Dwaraka, Christopher Gardner and colleagues investigated the molecular effects of a short-term vegan diet by instructing  half of each  pair of twins to consume an omnivorous diet that included 170-225 grams of meat, one egg, one egg and one egg. Half consumed dairy products daily, while the other half continued the vegan diet for the same period of eight weeks. 

The sample consisted of 77% women (32 people), the average age of participants was 40 years, and the average BMI was 26 kilograms per square meter. During the first four weeks of the study, participants ate  prepared meals, and during the last four weeks, they ate self-prepared meals  after receiving nutrition lessons from a health coach. 

The authors looked at the effect of the diet on  DNA methylation levels by analyzing blood samples taken from participants at baseline and at weeks four and eight of the study. They used the DNA methylation levels to infer the biological age of participants and their organ systems. 

At the end of the study, the authors observed a decline in  biological age estimates, known as the epigenetic aging clock, in participants who consumed a vegan diet, but not in those who consumed an omnivorous diet. They also observed declines in heart age, hormone balance, liver,  inflammatory and metabolic systems in participants who followed a vegan but non-omnivorous diet for eight weeks.  The authors note that it is unclear to what extent  the differences observed between participants consuming different diets are attributable to food composition. They note that differences in the caloric content of the meals given during the first 4 weeks of the study led participants following a vegan diet to lose, on average, 2 kg more weight than those following an omnivorous diet. 

 They suggest that these differences in weight loss may contribute to the epigenetic aging differences observed  between the two groups. Further studies are needed to examine the relationships between dietary composition, weight, and aging, as well as the long-term effects of a vegan diet, they added.