Vegan diet associated with more weight loss, better cholesterol control than Mediterranean diet

A low-fat vegan diet is associated with more consistent weight loss and better cholesterol control than the Mediterranean diet, according to new findings published in the Journal of the American College of Nutrition. The Mediterranean diet, meanwhile, led to a more significant drop in both systolic and diastolic blood pressure.  

A low-fat vegan diet and the Mediterranean diet are often viewed as two of the world’s premiere options for individuals who want to focus on the health of their heart and avoid cardiovascular complications. As the study’s authors wrote, they are “variations on a theme: one favors plant-based foods; the other consists of plant products exclusively.”

For this analysis, 30 study participants followed a low-fat vegan diet for 16 weeks and 32 participants followed a Mediterranean diet for 16 weeks.

The vegan diet included vegetables, grains, legumes and fruits. No specific meals were prepared or recommended. Vitamin B12 supplements were provided. The Mediterranean diet, meanwhile, included white meat, vegetables, fruits, legumes, nuts and seeds. Extra virgin olive oil was recommended instead of other fats or oils used during food preparation.

Alcoholic beverages were limited to all participants; women were allowed one per day, men were allowed two per day. Participants were also asked to continue taking any needed medications and not to specifically alter their exercise habits.

Overall, the vegan diet group lost an average of approximately 13 pounds. The Mediterranean diet group, meanwhile, saw no mean change in weight. Participants on the vegan diet also lost approximately 7.5 pounds more fat mass than those on the Mediterranean diet.

The vegan diet was also associated with drops in total cholesterol and LDL cholesterol, but the Mediterranean diet was tied to “no significant cholesterol changes.”

Systolic and diastolic blood pressure, the team noted, decreased for both groups—but that drop was more significant for the Mediterranean diet group.

“Previous studies have suggested that both Mediterranean and vegan diets improve body weight and cardiometabolic risk factors, but until now, their relative efficacy had not been compared in a randomized trial,” corresponding author Hana Kahleova, MD, PhD, director of clinical research for the Physicians Committee for Responsible Medicine, said in a statement. “We decided to test the diets head to head and found that a vegan diet is more effective for both improving health markers and boosting weight loss.”

The authors wrote that “the inclusion of fatty fish, dairy products and oils” is likely what limits weight loss for individuals who follow the Mediterranean diet.

The full study can be read here. Most of the authors represent the Physicians Committee For Responsible Medicine, a nonprofit organization dedicated to informing the general public about medical research and nutrition.

It's worth noting that the American Heart Association (AHA) has shown strong support for both diets. The group recommends the Mediterranean diet on its website, for example, and notes that vegetarian and vegan diets are beneficial and “easier than ever” to follow. Vegan diets still need to be healthy, the AHA emphasized—replacing meat with nothing but junk food, for example, could lead to significant health problems. More information from the AHA is available here.