Short-term vegan diet may slow aging, but questions remain

Following a vegan diet for a couple months may slow aging, new research hints.

However, these findings shouldn't be overhyped, experts cautioned, in part due to limitations in how the study was conducted.

In a small clinical trial that included 21 pairs of Healthy identical twins, one twin from each pair ate a vegan diet while the other twin followed an omnivorous diet, which included plants, meat, eggs and dairy. The twins followed these diets for eight weeks. The idea behind using identical twins is that, given their shared genetics, the iNFLuence of diet can then be isolated and studied more easily.

The twins, who were around 40 years old on average and mainly women, ate meals the researchers prepared for them for the first month of the study. For the second month, the participants cooked for themselves, after receiving nutrition classes.

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The researchers analyzed the participants' blood before they started their diets, four weeks in, and then again at the end of the study. They looked for changes in the chemical tags on top of DNA within the twins' cells; specifically, they assessed molecules called methyl groups, which latch onto DNA and change the extent to which specific genes are "switched on." They do this without altering the underlying DNA code — a phenomenon known as epigenetic modification.

Changes in methylation patterns are associated with accelerated rates of aging, and scientists have previously studied these changes in order to make "epigenetic clocks" that can be linked to organisms' maximum life spans.