This Diet Could Help Turn Back the Clock on Your Body's Biological Age

Key Takeaways

• A study comparing adult twins found that following a vegan diet for eight weeks reduced biomarkers of biological aging.
• Researchers used a method called DNA methylation to measure aging biomarkers in systems including the heart and metabolism.
• It's unclear whether these benefits came from eating a vegan diet, or related effects like eating fewer calories or losing weight.

Switching to a vegan diet may be one way to turn back time - at least when it comes to your biological age, a new study suggests.

Biological age focuses on how well your body functions instead of how old you are chronologically, and healthy lifestyle choices have long been seen as one way to potentially help people function like someone who has celebrated fewer birthdays. Slowing down our biological age can help us live longer, and also give us more years of life without chronic disease or disability, says co-lead study author Lucia Aronica, PhD , of Stanford University in California.

"While medical advances over the past century have significantly prolonged life expectancy, a substantial portion of the population still spends about one-third of their lives dealing with at least one age-related condition like heart disease or diabetes ," Dr. Aronica says. "Essentially, if we can slow our biological aging, we might reduce the risk of developing age-related diseases and live healthier longer, not merely extend the quantity of years we live."

One way to assess biological age is by focusing on a biological process known as DNA methylation, which involves molecular changes over time that turn different genes on and off. Some changes that happen with DNA methylation may age the body faster, while others may slow aging down.

For the new study, researchers looked for shifts in DNA methylation in 21 pairs of adult biological twins. Scientists asked one twin to switch to a vegan diet for eight weeks, while the other twin followed an healthy omnivorous diet.

A vegan diet is a stricter form of vegetarianism that excludes meat and all types of animal by-products. Going vegan means forgoing foods like milk, eggs, cheese, and yogurt that many vegetarians consume.

Vegan Diet Reduces Biological Age Markers

Overall, the twins who went vegan saw a significant reduction in markers of biological age based on changes in DNA methylation. These markers remained unchanged for the corresponding twins eating meat and other animal products, according to findings published in BMC Medicine .

Scientists also found going vegan was linked to decreases in the biological ages of the heart, hormone, liver, inflammatory and metabolic systems of twins who went vegan - but not in their siblings on the omnivorous diet.

It's hard to say exactly how much the changes observed in the study might have been directly caused by the vegan diet, as opposed to consuming fewer calories or losing weight while eating this way, the researchers note in the study.

The study is also too small, and too brief, to draw broad conclusions about whether everyone should go vegan to help reduce their biological age, says co-lead study author Varun Dwaraka, who completed the research while at Stanford University.

"We cannot predict the long-term effects of a vegan diet," Dwaraka says. "Our study observed changes linked to the diet, but could not pinpoint which specific aspects - such as eating more vegetables, eating less meat, or naturally consuming fewer calories - were driving these changes. Although we cannot provide specific guidelines based on this brief study, generally incorporating one or more of these aspects into your diet is likely to be beneficial."

How a Vegan Diet May Improve Biological Age

Experts consider diet one of the main modifiable factors that can impact our biological age, says Douglas Vaughan, MD , a professor emeritus and director of the Potocsnak Longevity Institute at the Northwestern University Feinberg School of Medicine in Chicago.

" Plant-rich diets are high in anti-inflammatory compounds, which may help slow the pace of biological aging," says Dr. Vaughan, who wasn't involved in the new study. "Vegan diets are generally high in nutrients that support healthy DNA methylation, including antioxidants."

Even though the exact impact of a vegan diet on biological age isn't yet clear, there are several possible ways that it may help, says Kayli Anderson, RDN , a founder of the company Plant-Based Mavens who serves on the faculty of the American College of Lifestyle Medicine in St. Louis.

"For example, a plant-based diet may slow biological aging because of high intake of fiber and fruits and vegetables, or its ability to reduce inflammation," says Anderson, who wasn't involved in the new study. "Or the aging benefits may be due to the absence of things like animal fats or red meat."

Anyone looking to add more plants to their diet should focus on what's sustainable over the long term, even if it's not a strict vegan diet, Anderson advises.

"It's our eating habits over time that help shape our health," Anderson says. "Simply increasing the amount of plant-based foods you eat is good for your health, whether you're vegan or not."

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Sources

1. Dwaraka VB et al. Unveiling the epigenetic impact of vegan vs. omnivorous diets on aging: insights from the Twins Nutrition Study (TwiNS). BMC Medicine . July 29, 2024.

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Lisa Rapaport

Author

Lisa Rapaport is a journalist with more than 20 years of experience on the health beat as a writer and editor. She holds a master's degree from the UC Berkeley Graduate School of Journalism and spent a year as a Knight-Wallace journalism fellow at the University of Michigan. Her work has appeared in dozens of local and national media outlets, including Reuters, Bloomberg, WNYC, The Washington Post, Los Angeles Times , Scientific American , San Jose Mercury News , Oakland Tribune , Huffington Post, Yahoo! News, The Sacramento Bee , and The Buffalo News . See full bio See Our Editorial Policy Meet Our Health Expert Network