Can a vegan diet boost your metabolism?
Dietary vegans follow a plant-based diet that excludes all animal products, from meat to eggs to milk to animal-derivatives.
Some researchers believe following a low-fat vegan diet may help you lose weight, in part because it helps speed up your metabolism (the rate at which calories are burned). That’s the hypothesis of a study now underway by the nonprofit Physician’s Committee for Responsible Medicine.
The committee’s president Neal Barnard found this to be true in a study he led in 2005 and reported on in the Journal of the American Medical Association. Postmenopausal women boosted their metabolism by about 16 percent on a low-fat vegan diet.
But that study had no control group — that is, one with participants following their usual diet to compare with those on the low-fat vegan one.
Nutrition classes included
Now, the Physician’s Committee is recruiting overweight participants for a new 16-week study, where half will be randomly chosen to follow a low-fat vegan diet and take nutrition and cooking classes at the group’s office in NW Washington, about seven blocks south of the Tenleytown Metro station. They will also have a one-on-one consultation with a registered dietician.
The other half of the participants will be told to just continue with their regular eating pattern for 16 weeks, but will have the opportunity to take the classes at a later time.
What might explain the boost in metabolism that was found in the earlier vegan diet study?
“By taking the animal products, oils and other fatty foods out of our diet, we enable our bodies to process energy at a faster rate and run efficiently,” said Dr. Hana Kahleova, director of clinical research at the Physicians Committee.
In addition, “This diet is not just helpful for losing weight. It’s also a healthy diet overall. It’s also good for the health of our heart, our risk of diabetes, cancer and chronic diseases,” she said.
Volunteers being sought
Participants for both arms of the study must have a body mass index (BMI) of 28 to 40, meaning they are overweight to severely obese. They cannot have diabetes.
Those in the low-fat vegan arm of the study will not be given a precise list of foods or meals to prepare, but will be given instructions on healthy fats and plant-based foods they can include.
At the beginning of the study, all participants will have a blood test that measures glucose sensitivity, another aspect of the diet that researchers will examine. Impaired glucose tolerance can lead to diabetes.
They will also have a dexa scan to measure body fat. The 10- to 15-minute test uses weak x-rays to detect body composition.
A third test is called indirect calorimetry. It measures carbon dioxide and oxygen levels to help determine one’s metabolism rate. In this test, participants lie on a table with their heads in a clear covering connected to a computer that measures the air they exhale. The test takes about 20 minutes.
These three tests will be repeated 16 weeks later, at the end of the study.
Kahleova said participants in the diet portion of the study may experience lasting
effects.“It seems that even after people discontinue a vegan diet, they have better weight management than people not on a vegan diet. That makes us think that there are some longer-term [beneficial] effects,” she said.
Those who complete the study will be paid $100 in compensation.
To learn more, call toll free (855) 788-3918 or see www.physicianscommittee.org/study.