Association between Vegetarian Diet and Obesity

Worldwide obesity has more than doubled since 1980. In 2014, more than 1.9 billion adults were overweight; of these, over 600 million were obese. Obesity is caused by an interaction between the environmental factors, genetic predisposition, and human behavior. The prevalence of obesity proves that none of the strategies on weight management were successful till now. In order to reach ideal weight, healthy weight loss and prevention of weight regain are important. The western dietary pattern characterized by eating red meat, eggs, refined grain is positively associated with obesity whereas observational studies announced that vegetarians have a lower BMI than omnivores, but its role as the best way to control and prevent obesity is still debated. At present, there are limited prospective data on association between vegetarian dietary patterns and healthy body weight change. Electronic literature search was conducted on websites such as PubMed, Science direct and Google scholar and most of searches were focused on 2011-2015. Much of the data on association between vegetarian diets and BMI are from studies whose primary outcome was not obesity although a few well-designed studies have directly examined the relation between vegetarian eating patterns and BMI. According to many scientific literatures, vegetarian diets reduce the risk factors of many chronic diseases such as obesity and having vegetarian diet is inversely related to body mass index (BMI), overweight and obesity.