It seems like it happens every week: one svelte celebrity or another comes out of the nutritional closet as a vegetarian. Even cheeseburger-loving former President Bill Clinton announced he was a vegan in 2011, attributing a 20-lb. weight loss to the all-plant diet. The truth is that "go veg -- lose weight" isn't quite as simple as it first appears, but a vegetarian diet can be the key to long-term weight loss if planned correctly.
Family physician and nutrition expert Dr. Joel Fuhrman says that nutrient density -- getting the most nutritional goodness per calorie -- is the key to successful weight loss. As it happens, the most nutrient-dense foods are those that come from plants. When compared calorie-to-calorie, leafy green vegetables like kale have more protein, fiber, vitamins and minerals than lean sirloin steak, without any of the cholesterol or saturated fat. In addition, you get a lot more food for 100 calories of lettuce -- 714 g by weight -- than you do of steak -- 24 g. It is this nutrient density that gives vegetarians the edge -- they get more food and nutrients for far fewer calories than their meat-eating counterparts.
Portion Control -- Or Not
Most dieters worry about portion control, and skimpy portions can make it difficult to stick to any meal plan. Vegetarians have a edge here, too. A 2005 study by the Physician's Committee for Responsible Medicine, or PCRM, showed that a low-fat vegan diet could cause a weight loss of 1 lb. per week without counting calories, measuring portion sizes or even exercising. The high amount of fiber and volume in the plant-based diet, coupled with fewer calories from fat, meant that vegetarians were naturally decreasing calorie intake while still feeling satisfied. As an added bonus, vegetarians burned more calories after meals than their meat-eating diet counterparts.
What to Eat
Successful vegetarian dieters focus on fruits and vegetables as the main portion of their diets, along with whole grains and beans. Fats are limited, and animal products including meat, chicken, fish are eliminated entirely. Both Dr. Fuhrman and the PCRM recommend elimination of full-fat milk and cheeses and restriction or elimination of low and non-fat dairy.
How to Fail
While a vegetarian diet is very healthy when planned correctly, some practices will sabotage your weight-loss efforts or even cause weight gain. Don't load up on breads, cereals and pastas, as these items are high in calories and don't offer much nutrition. Likewise, processed meat substitutes and sugary foods should be limited. Vegans -- those who omit all animal products -- should take a daily B-12 vitamin supplement. This nutrient is not easily found in plant foods and a shortage can have adverse affects on physical health.