Plant-based diet lowers type 2 diabetes risk, but there's a big catch

Eating a plant-based diet may significantly lower type 2 diabetes risk, according to a newly published Harvard study. The research builds upon a growing base of studies highlighting the potential benefits of following a mostly meat-free diet, including a lowered risk of developing cardiovascular disease. There's a big catch, however, with only certain plant-based diets offering the greatest benefits.

Plant-based diets and diabetes

According to a meta-analysis out of Harvard's T.H. Chan School of Public Health, people who primarily eat plant-based foods have a lowered risk of developing type 2 diabetes, a growing health issue impacting millions of people around the world.

Plant-based foods are meals that emphasize plant ingredients rather than animal-sourced ingredients, including grains, leafy greens, nuts, fruits and vegetables, and similar food items. A total of nine studies were analyzed as part of this research, which found that people who had high adherence levels to plant-based diets had lowered diabetes risk compared to people who had low dietary adherence.

The researchers looked at more than 307,000 participants with more than 23,000 cases of type 2 diabetes, as well as diets that were predominately plant-based and plant-based diets that emphasized healthy foods with low levels of unhealthy foods.

There's a catch

Though an overall predominately plant-based diet lowered one's risk of developing type 2 diabetes by 23-percent, the greatest benefit was seen in individuals who consumed healthy foods. Switching to a plant-based diet may not be adequate enough to lower one's risk if the diet is primarily composed of unhealthy foods, such as vegan snacks and other highly processed foods, however.

The researchers point toward multiple potential benefits resulting from predominately plant-based diets that could lower type 2 diabetes risk, including lowered blood pressure, increased insulin sensitivity, reduced body weight, and reduced systemic inflammation. These positive effects were observed in cases where the diets were predominately composed of healthy foods, however.

What you can do

Qi Sun, Department of Nutrition associate professor and the study's senior author, explained:

Overall, these data highlighted the importance of adhering to plant-based diets to achieve or maintain good health, and people should choose fresh fruits and vegetables, whole grains, tofu, and other healthy plant foods as the cornerstone of such diets.

Based on the studies the researchers analyzed, a predominately healthy plant-based diet is one that focuses on fruit, vegetables, whole grains, legumes, and nuts, but that may also contain low or modest amounts of animal products, white flour, sugar, and potatoes.