In a new study, vegans and vegetarians lost more weight than omnivores, and kept it off for more than six months.

Counting calories may soon be a thing of the past.

A new study sheds light on a weight loss model that involves maintaining a specific diet, rather than tracking calories. Brie Turner-McGrievy, an assistant professor at the University of South Carolina, studied 63 individuals who were placed into five diet groups—vegan, vegetarian, pesco-vegetarian, semi-vegetarian, and omnivorous—for an eight-week span.

The vegans and vegetarians lost 8.2 to 9.9 pounds on average, while omnivores lost 5.1 pounds. The omnivores still lost weight, she notes, but the vegans and vegetarians lost more.

Instead of monitoring their caloric intake, study respondents simply ate within their diet group, focusing on foods that were low in fat and low on the glycemic index.

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Turner-McGrievy followed up on the study participants two months after the study ended. At that time, the vegans, vegetarians, and pesco-vegetarians had all lost more weight than the omnivores.

Six months after the study, the vegans had lost more than any of the other groups, even though they only adhered to the diet about 30 to 40 percent of the time. The vegans had dropped about 7.5 percent of their body weight, while vegetarians were down about 5.8 percent.

The study not only shows that a plant-based diet may help you lose weight; it also demonstrates the benefits of a weight loss model that has nothing to do with counting calories and subtracting how many you burn after a good sweat session.

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Keeping meat off your plate is not a surefire way to drop pounds. You have to be selective about what you eat and drink regardless of your diet, says Christopher Gardner, an associate professor at the Stanford University School of Medicine.

Gardner explains that it makes sense that the vegans and vegetarians lost more weight because most of the foods they ate are low in saturated fat. A vegetarian himself, Gardner said that shifting to a plant-based diet for ethical reasons—like not harming animals—might help you stick with the commitment instead of doing so only to lose weight.

While Turner-McGrievy says eating only from items in a particular food group can be liberating for people who are frustrated by counting calories, it doesn’t appeal to everyone.

Sharon Palmer, a registered dietitian and author of The Plant-Powered Diet, says to be careful which foods you eat if you take the vegan or vegetarian route.

“A lot of things in the junk food category can be considered vegan,” Palmer said. “You can load up on a high-calorie, empty nutrient foods and have just as many problems with weight as an omnivore.”

Not ready to cut ties with meat? Try swapping out a few meals for plant-focused ones.

Palmer suggests picking a vegetable or legume instead of a meat and planning the meal around that. Not only might it help you lose weight, it will also likely bring more nutrients into your diet.

“Once you get it, it’s easy,” she said.