Just some sharing....

Research shows that people who follow a vegetarian eating plan, on average, eat fewer calories and less fat than non-vegetarians. They also tend to have lower body weights relative to their heights than non-vegetarians. Choosing a vegetarian eating plan with a low fat content may be helpful for weight loss. But vegetarians—like non-vegetarians—can make food choices that contribute to weight gain, like eating large amounts of high-fat, high-calorie foods or foods with little or no nutritional value.

Vegetarian diets should be as carefully planned as non-vegetarian diets to make sure they are balanced. Nutrients that non-vegetarians normally get from animal products, but that are not always found in a vegetarian eating plan, are iron, calcium, vitamin D, vitamin B12, zinc, and protein.

Hope it helps.
Cheers!
Patrick