Are Vegetarian Diets Really That Effective?

This study found that vegetarian dieters not only lost weight more effectively than those on conventional low-calorie diets but also improve their metabolism by reducing muscle fat.

For many, myself included, vegan and vegetarian diets hold little allure. As a dedicated meat eater and lover of all things bacon, it’s tough to think about giving up eggs, cheese, chicken breast, whey protein, milk, steak, and all the other delicious animal-based foods that make up my regular meals.

But a recent study made a discovery that has even me seriously considering making the change to a plant-based diet. In June 2017, the Journal of the American College of Nutrition published the results of a study conducted by the Physicians Committee for Responsible Medicine (PCRM) in Washington DC.

Researchers set 74 diabetic subjects on one of two diets: an anti-diabetes diet, created by following the official recommendations of the European Association for the Study of Diabetes; or a vegetarian diet consisting of nuts, fruits, grains, veggies, legumes, and just one portion of low-fat yogurt per day. Also, the dieters consumed 500 calories fewer per day.

At zero, three, and six months of the diet, the participants weighed in, and the weight loss totaled. The dieters following the conventional anti-diabetes diet lost an average of 3.2 kg. However, the vegetarian dieters lost a whopping 6.2 kg on average.

But the study didn’t stop at just body weight. The researchers used MRIs to study the adipose tissue of both groups. Both diets led to a decrease in subcutaneous fat (fat under the skin). However, when it came to subfascial fat, only the vegetarian diet achieved visible results. Even more, the amount of intramuscular fat loss was significantly greater among the vegetarian dieters.

This is an important outcome, for various reasons. First off, it makes it clear that a vegetarian diet can lead to visible weight and fat loss results. But it’s not just the fat stored beneath your skin—it’s also the fat around your organs, the type of lipids that can impair organ function, increase insulin resistance, and slow metabolism. By decreasing subfascial and intramuscular fat, you can drastically reduce the chance of metabolic syndrome while combatting obesity.

However, like all research, we need to look at the people behind this research. Dr. Kahleová, lead author and Director of Clinical Research at the PCRM, said: “Vegetarian diets proved to be the most effective diets for weight loss. However, we also showed that a vegetarian diet is much more effective at reducing muscle fat, thus improving metabolism. This finding is important for people who are trying to lose weight, including those suffering from metabolic syndrome and/or type 2 diabetes. But it is also relevant to anyone who takes their weight management seriously and wants to stay lean and healthy.”

PCRM is considered to be an advocacy group against animal testing, among other things, and is known for promoting vegetarianism. However, it doesn’t necessarily mean the research here is wrong. For the sake of full disclosure, we say the source needs to be considered. We are also aware that there is a certain amount of anti-PCRM push back, some from industries that are impacted by the group’s stance, and some by traditional physician’s organizations. Again, this doesn’t mean PCRM is wrong or misrepresenting the facts. There’s way too much black and white outrage about what is right and wrong when it comes to what goes in your stomach.

We’ll leave it up to you to figure out how you weigh these findings and while we don’t discount them, we don’t necessarily think that they’re gospel. It’s a lot more complicated than that. It would be so much easier if everyone’s body worked in exactly the same way, but that’s not the case. There are billions of individual physiological specimens walking the planet and they all react differently to nutrition and exercise and all the good things we like to study on these pages.


1. Hana Kahleova, Marta Klementova, Vit Herynek, Antonin Skoch, Stepan Herynek, Martin Hill, Andrea Mari, Terezie Pelikanova. “The Effect of a Vegetarian vs Conventional Hypocaloric Diabetic Diet on Thigh Adipose Tissue Distribution in Subjects with Type 2 Diabetes: A Randomized Study.” Journal of the American College of Nutrition, 2017; 1.