Eating a vegan diet increases consumption of plant-based foods-including those defined as “unhealthy” by the plant-based diet index-leading to greater weight loss than the Mediterranean diet, finds a new analysis by the Physicians Committee for Responsible Medicine\u00a0published in\u00a0Frontiers in Nutrition.\u00a0<\/p>\n
Avoiding animal products; eating foods like potatoes and refined grains, which are defined as “unhealthy” by the plant-based diet index; and avoiding added oils and nuts, which are defined as “healthy” by the plant-based diet index, all contributed to weight loss.<\/p>\n
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Our research shows that even when a low-fat vegan diet includes so-called unhealthy plant-based foods-as defined by the plant-based diet index-like refined grains and potatoes, it’s better than the Mediterranean diet for weight loss, because it avoids animal products and added oils.”<\/p>\n
\n <\/p>\nHana Kahleova, MD, PhD, director of clinical research\u00a0at the Physicians Committee for Responsible Medicine and lead author of the study<\/p>\n
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The new research is a secondary analysis of\u00a0a previous Physicians Committee study comparing a low-fat vegan diet to a Mediterranean diet. The study randomly assigned 62 overweight adults to either a low-fat vegan diet, which consisted of fruits, vegetables, grains, and beans, or a Mediterranean diet, which focused on fruits, vegetables, legumes, fish, low-fat dairy, and extra-virgin olive oil<\/a>, for 16 weeks. Neither group had a calorie limit. Participants then went back to their baseline diets for a four-week washout period before switching to the opposite group for an additional 16 weeks. The study found that a vegan diet is more effective for weight loss than a Mediterranean diet, and has better outcomes for weight, body composition, insulin sensitivity, and cholesterol levels.<\/p>\n
In\u00a0this secondary analysis, the participants’ dietary records were used to assess the relationship of a plant-based diet index (PDI), healthful PDI (hPDI), and unhealthful PDI (uPDI) with weight loss on both the vegan diet and Mediterranean diet. “Healthful” plant-based foods, as defined by the PDI system, include fruits, vegetables, whole grains, nuts, legumes, oils, coffee, and tea. “Unhealthful” plant-based foods include fruit juice, sugar-sweetened beverages, refined grains, potatoes, and sweets. The PDI system assigns scores as follows:<\/p>\n
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- PDI: Score increases with more plant-based foods overall.<\/li>\n
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- hPDI: Score increases with more “healthful” plant-based foods and fewer “unhealthful” plant-based foods.<\/li>\n
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- uPDI: Score increases with more “unhealthful” plant-based foods and fewer “healthful” plant-based foods.<\/li>\n
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In the analysis, the PDI score increased significantly on the vegan diet and did not change on the Mediterranean diet; the hPDI score increased on both diets; and uPDI increased on the vegan diet and decreased on the Mediterranean diet.<\/p>\n
The increases in the PDI and uPDI scores, which were seen only the low-fat vegan diet, were associated with weight loss. The changes in hPDI, which were seen on both diets, were not associated with changes in body weight.<\/p>\n
The majority of the increases in the PDI, hPDI, and uPDI scores came from avoiding animal foods on a vegan diet. Reducing the consumption of oils and nuts further increased the uPDI score by points on a vegan diet. These findings suggest that replacing animal products with plant-based foods, and reducing the consumption of oil and nuts, may be successful strategies for weight loss.<\/p>\n
Source:<\/p>\n
Physicians Committee for Responsible Medicine<\/a><\/p>\n
Journal reference:<\/p>\n