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STANFORD, Calif. — A vegan diet can improve heart health in as little as eight weeks, a new study explains. This research, focusing on identical twins, compared the effects of vegan and omnivore diets, discovering notable enhancements in cardiovascular health with a vegan diet. The most significant changes appeared within the first four weeks after adopting a vegan diet.

Those on the vegan diet experienced considerably lower levels of cholesterol, insulin, and body weight than their omnivorous counterparts — who ate meat, fish, and greens. Notably, vegan participants exhibited a roughly 20-percent decrease in fasting insulin, which reduces diabetes risk, and they lost an average of 4.2 pounds more than non-vegans.

For this study, researchers from Stanford University analyzed 22 pairs of identical twins over three months. The decision to use identical twins, as detailed in the study published in JAMA Network Open, was to minimize the impact of variables such as genetic differences, upbringing, and lifestyle choices.

The team carefully selected healthy individuals without cardiovascular diseases, assigning one twin from each pair to either a vegan or omnivore diet.

“Not only did this study provide a groundbreaking way to assert that a vegan diet is healthier than the conventional omnivore diet, but the twins were also a riot to work with,” says Christopher Gardner, PhD, the Rehnborg Farquhar Professor at Stanford Medicine, in a media release. “They dressed the same, they talked the same and they had a banter between them that you could have only if you spent an inordinate amount of time together.”

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Both the vegan and omnivore diets in the study were health-focused, including a variety of vegetables, legumes, fruits, and whole grains, while excluding sugars and refined starches.

Participants recorded their dietary intake and maintained food logs. Out of 44 participants, 43 successfully completed the study, which, according to the research team, suggests the practicality and achievability of these diets.

“Our study used a generalizable diet that is accessible to anyone, because 21 out of the 22 vegans followed through with the diet,” explains Gardner, who is a professor in the Stanford Prevention Research Center. “This suggests that anyone who chooses a vegan diet can improve their long-term health in two months, with the most change seen in the first month.”

“Based on these results and thinking about longevity, most of us would benefit from going to a more plant-based diet,” the study author adds.

Although Prof. Gardner, who has been mostly vegan for the last 40 years, acknowledges that most people probably won’t go fully vegan, he believes that a nudge in the right direction will still improve their health.

“A vegan diet can confer additional benefits such as increased gut bacteria and the reduction of telomere loss, which slows aging in the body,” Gardner concludes.

“What’s more important than going strictly vegan is including more plant-based foods into your diet. Luckily, having fun with vegan multicultural foods like Indian masala, Asian stir-fry and African lentil-based dishes can be a great first step.”

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South West News Service writer Isobel Williams contributed to this report.

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