PCRM's Weight Loss Study
Overweight is an important risk factor for cancer, especially breast cancer. But what is the best way to lose excess weight? Many research studies, including those at PCRM, suggest that a low-fat, vegan diet is the most effective.
Research assistant Matthew Fritts and
PCRM president Neal D. Barnard, M.D., examine study results.
In February, PCRM embarked on a weight-loss study that put vegan foods to the test. Twenty-six post-menopausal women participated in the 14-week study. Half followed a low-fat diet modeled after the National Cholesterol Education Program Step II diet, promoted by government health initiatives and the American Heart Association. The other half consumed only low-fat, vegan foods—containing no animal products, including meat, dairy, or eggs—with no restriction on quantity.
Participants met every Tuesday night at the PCRM office for cooking instructions from Judy Harris and health and nutrition lectures by lead researcher Neal Barnard, M.D., on topics including cholesterol, stress eating, how genes affect weight, and cancer risk factors.
Without counting calories or limiting the quantity of food they ate, the women in the vegan group lost an average of 15 pounds compared to 10 pounds for the Step II group. They were enthusiastic about the freedom to eat without the feelings of deprivation or hunger that previous diets had caused. Many report that they plan to stick with vegan foods and are delighted that their weight continues to drop. Some women on the Step II diet found it complicated and difficult to continue on a long-term basis, and weight gain often resulted. PCRM researchers will follow the participants for two years, monitoring weight changes, blood pressure, and satisfaction with results.
Going Vegan and Loving It!
For many research volunteers, adopting a vegan diet was filled with surprises. One participant said she had been dieting since age 14, and although several diets allowed her to lose weight, she always felt deprived and often ended up gaining back more weight eventually. In taking part in the vegan weight-loss study, the 51-year-old lost 22 pounds in 14 weeks and reports she never feels hungry. "I like rice, potatoes, bread, legumes, vegetables, and fruit, and since I'm not limited to certain amounts any more, I always feel satisfied," she says. She plans to continue following a vegan diet and says, "It seems like the logical solution to remaining healthy."
As a breast cancer survivor at age 60, another participant was interested in losing weight as a measure of protection from recurrence of the disease and as a means of lowering her risk for other types of cancer. Although she expected the vegan diet to be difficult to follow, she began to experiment with new foods and even found healthful replacements for her "comfort foods." After learning about the nutritional and antioxidant value of various foods, her perceptions changed. She has lost 32 pounds—and counting—and plans to continue a vegetarian diet until she reaches her goal weight. "I feel that I have started a new life," she comments. She has also incorporated exercise into her routine and says, "I am healthier now than I have been in my entire life." Her advice to others thinking about a vegan diet? Try it for two weeks, experiment with new foods, and embrace it as part of a lifestyle change.