Oh my veggies! Can a vegetarian diet help you lose weight?

The Bottom Line

  • The number of overweight or obese adults is on the rise globally. 
  • Research shows that lacto-ovo vegetarian and vegan diets can help you lose weight in the short-term. Vegan diets, and vegetarian diets paired with lower caloric intake produce the greatest weight loss. 
  • More research is needed on the long-term weight loss benefits of vegetarian diets.

Losing weight and keeping it off is no easy task. Should you go low-carb, gluten-free, Mediterranean, raw, paleo? What about trying a good old vegetarian diet? Or would it be better to go vegan? When you want to shed pounds, it’s hard to know which direction to go.

Globally, almost 37% of adults were considered overweight or obese in 2013; a number which has been increasing for at least four decades (1).

There’s no question that maintaining a healthy weight is good for you. Being overweight or obese increases your risk of numerous health conditions, including high blood pressure, diabetes, heart disease, stroke, sleep apnea, mental illness, and cancer (2).

Vegetarianism is also on the rise. In 2015, about 3 million Canadians – or 8% of the population – were eating a vegetarian or a mostly vegetarian diet, according to a poll conducted by the Vancouver Humane Society (3). Vegetarians can be divided into two main types. Lacto-ovo vegetarians avoid meat but allow milk and eggs, while vegans eat a plant-based diet with no animal products at all (4). Research has linked vegetarian diets to a decreased risk of chronic diseases such as diabetes and heart disease (5).

Vegetarian diets can promote weight loss because they focus on nutrient-dense, low-calorie foods like fruits, vegetables, whole grains, nuts, seeds and soy. Vegan diets go even further and cut out calorie-rich foods like cheese. But being vegetarian doesn’t automatically mean consuming fewer calories. After all, many vegetarian and vegan foods pack a high-calorie punch – think soy cheese, fried foods, snack bars, and even cookies and pie (6).

So, can a vegetarian diet help with weight loss? 

What the research tells us

People who follow a vegetarian diet are more likely to lose weight compared to people who follow non-vegetarian nutritional plans, and vegans tend to lose more weight than lacto-ovo vegetarians. Additionally, people who follow either a lacto-ovo vegetarian diet or vegan diet and purposefully eat fewer calories experience more weight loss than individuals on these diets who do not eat less calories. The weight loss benefit of vegetarian diets has been shown to last for at least 12 months, and possibly longer, but more research is needed to determine whether these diets control weight in the long term (5).

Eliminating animal-based products from your diet doesn’t guarantee that the pounds will shed themselves. But if you feel motivated and make good food choices, a lacto-ovo vegetarian or vegan diet can help you lose weight.

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Author Details


  1. Ng M, Fleming T, Robinson M, et al. Global, regional, and national prevalence of overweight and obesity in children and adults during 1980-2013: A systematic analysis for the Global Burden of Disease Study 2013. Lancet. 2014; 384(9945):766-781.  
  2. Centers for Disease Control and Prevention. Adult obesity causes & consequences. [Internet] 2017. [cited November 2017]. Available from https://www.cdc.gov/obesity/adult/causes.html 
  3. Pippus A. Almost 12 million Canadians now vegetarian or trying to eat less meat! [Internet] 2015. [cited November 2017]. Available from http://www.vancouverhumanesociety.bc.ca/almost-12-million-canadians-now-vegetarian-or-trying-to-eat-less-meat  
  4. Huang R, Huang C, Hu F, et al. Vegetarian diets and weight reduction: A meta-analysis of randomized controlled trials. J Gen Intern Med. 2016; 31(1):109-116. doi: 10.1007/s11606-015-3390-7.
  5. Fraser GE. Vegetarian diets: What do we know of their effects on common chronic diseases? Am J Clin Nutr. 2009; 89(5):1607S-1612S. doi: 10.3945/ajcn.2009.26736K. 
  6. Zeratsky K. If I switch to a vegetarian diet, will I lose weight? [Internet] 2015. [cited November 2017].

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