Skip to content

This Diet Is the Key to Burning Fat, New Study Says

You could burn nearly 19% more calories following this eating plan.

Your metabolism controls how fast your body burns the calories you consume. If you've been trying to lose weight but haven't had much luck, it's natural to wonder if the root of the problem is attributable a slow metabolism. In fact, you may be onto something (here are 15 warning signs your metabolism is set to "sluggish"). But, don't worry because new research suggests there's an easy way to rev up your metabolism.

You could reverse this issue right now, says a new study published in the Journal of the American Medical Association, which found that a low-fat, vegan diet enabled overweight adults to increase their calorie burn by nearly 19% in just 16 weeks. (Related: 15 Underrated Weight Loss Tips That Actually Work.)

A team of scientists led by Hana Kahleova, MD, Ph.D., director of clinical research at the Physicians Committee for Responsible Medicine, already knew that plant-based diets can help people lose weight, so they took it a step further and explored why that's the case. Together, they recruited over 3,000 adults who wanted to lose weight and selected 244 (211 of which were females with the averaxge age of 54) who were overweight but otherwise healthy and didn't have a history of diabetes. For the next 16 weeks, half followed a low-fat, vegan diet with no calorie limit that consisted of 75% carbohydrates, 15% protein, and 10% fat. The other half made no dietary changes.

At the start of the study, Dr. Kahleova's team measured and recorded everyone's weight, body composition, and cholesterol levels, as well as a number of indicators of metabolic function, including "afterburn" i.e., how many calories were burned after eating a standardized meal. After 16 weeks, when measurements were taken again, those on the plant-based diet had, on average, lost 14 pounds and increased their afterburn by nearly 19%. 

"It was exciting to see such profound health improvements in such a short period of time," Dr. Khaleova told Eat This, Not That! In addition to weight loss and increased afterburn, the plant-based group saw:

  • significant fat loss, including dangerous belly fat
  • a significant decrease in insulin resistance, which is associated with diabetes and prediabetes
  • dramatically lower levels of LDL cholesterol, or the type that's harmful to heart health

The control group saw no such changes, despite the fact that both groups (on average) self-reported eating fewer calories and exercising slightly less than usual during the study period. Dr. Kahleova's team concluded that a low-fat, vegan diet leads to weight loss by both reducing overall caloric intake and speeding up metabolism.

"A plant-based diet is an affordable and accessible option for anyone who is looking to improve their health," Dr. Kahleova says. At the same time, she anticipates that future studies will address to what extent this diet strategy can help people with diabetes.

If you plan to adopt a low-fat, vegan diet, it may be worth noting that the people on the vegan diet in Dr. Kahleova's study were given extra vitamin B12, which can be lacking in strictly plant-based diets. Before you begin adding supplements, here are the 6 things to keep in mind.

To stay on top of all the latest weight loss news, sign up for our newsletter, and you'll have it delivered straight to your inbox daily. 

Lauren Cahn
Lauren Cahn is a food, health, and culture writer whose work has appeared online and in print for Reader's Digest as well as Health Digest, Huffington Post, Taste of Home, and others. Read more about Lauren