Researchers find that a vegan diet high in legumes helps people lose weight.
According to recent research from the Physicians Committee for Responsible Medicine that was published in the Journal of the Academy of Nutrition and Dietetics, a vegan diet enhances diet quality, which results in lower weight and enhanced insulin sensitivity. Increased consumption of legumes and reduced intake of meat, fish, and poultry were the two factors most strongly related to weight loss.
“Our research shows that the best way to improve the quality of your health is to improve the quality of the foods you eat,” says Hana Kahleova, MD, Ph.D., director of clinical research at the Physicians Committee and a study co-author. “That means avoiding animal products and eating a vegan diet rich in fruits, vegetables, grains, and beans.”
244 overweight people who participated in the 16-week trial were split into two groups at random: those who made no dietary modifications and those who followed a low-fat vegan diet consisting of vegetables, grains, legumes, and fruits without calorie limitations. Weight, body fat mass, insulin sensitivity, and diet quality were all monitored by researchers. 219 people who finished the whole study and sent in their final diet records were included in the final data analysis.
Participants on the vegan diet lost an average of 13 pounds and 9.1 pounds of fat mass. Body weight and fat mass did not decrease in the group that made no diet changes. In the vegan group, increases in fruit, legume, meat alternative, and whole grain intake and decreases in animal products, added oils, and animal fats were associated with weight loss:
- Fruit: Increased intake of whole fruit was associated with a decrease in body weight.
- Legumes and Meat Alternatives: Increased legume consumption was associated with decreased weight, fat mass, and visceral adipose tissue. Consuming more meat alternatives, including tofu, tempeh, and veggie burgers, was associated with a decrease in body weight.
- Grains: Increased consumption of whole grains was associated with decreased body weight and fat mass.
- Eggs and Dairy Products: Decreased egg intake was correlated with decreased weight. Decreased high-fat dairy intake was associated with decreased weight and fat mass.
- Meat, Fish, and Poultry: Reductions in the combined intake of total meat, fish, and poultry were associated with weight loss and a decrease in fat mass.
- Added Fats: Decreases in intake of added animal fats were associated with decreases in weight and fat mass. Decreased intake of added oils also correlated with decreases in weight and fat mass.
The vegan group also experienced improvements in insulin sensitivity.
The vegan group’s diet quality, measured by the Alternative Healthy Eating Index-2010 (AHEI) score, also increased by 6 points on average in contrast to no significant change in the group that did not make a diet change. The AHEI was developed by researchers at the Harvard School of Public Health to identify dietary patterns associated with a lower risk of chronic disease. The index is comprised of foods to eat more often, such as fruits and vegetables, and those to eat less often, such as red and processed meat. The higher the AHEI score, the lower the risk for chronic disease.
Reference: “Changes in Food and Nutrient Intake and Diet Quality on a Low-Fat Vegan Diet Are Associated with Changes in Body Weight, Body Composition, and Insulin Sensitivity in Overweight Adults: A Randomized Clinical Trial” by Lelia Crosby, BA, RD, LD, Emilie Rembert, BS, Susan Levin, MS, RD, CSSD, Amber Green, BS, RD, LD, Zeeshan Ali, Ph.D., Meghan Jardine, MS, MBA, RDN, LD, CDE, Minh Nguyen, MS, RD, Patrick Elliott, BS, Daniel Goldstein, BA, Amber Freeman, Meka Bradshaw, Danielle N. Holtz, Richard Holubkov, Ph.D., Neal D. Barnard, MD and Hana Kahleova, MD, Ph.D., 19 April 2022, Journal of the Academy of Nutrition and Dietetics.