Although vegetarian diets aren't for everybody and take careful planning to ensure your daily nutrient needs are met, those who follow a vegetarian meal plan can expect several health benefits. For example, a 2010 review in "Nutrition in Clinical Practice" reports that vegetarians generally have lower body mass indexes than nonvegetarians. Several different types of vegetarian diets are available to choose from, but avoiding meat is the one thing they all have in common.
People following pescatarian diets avoid red meat and poultry but do consume fish and other seafood. In contrast, nonvegetarians generally eat all types of animal-based food products, including red meat, poultry and seafood. Both nonvegetarian and pescatarian dieters include eggs, dairy products and plant-based foods in their meal plans. A 2009 study published in "Diabetes Care" reports that pescatarian dieters have lower body mass indexes and lower risks of developing type-2 diabetes than meat eaters.
Lacto- and Ovo-Vegetarians
Many vegetarian dieters add eggs, dairy foods or both to their diet in addition to eating a variety of plant-based foods. Lacto-ovo vegetarians avoid meat, poultry and seafood, but eat both eggs and dairy products -- such as milk, yogurt and cheese. Lacto-vegetarians consume dairy foods but avoid meat, poultry, seafood and eggs. Ovo-vegetarians eat eggs but avoid all dairy foods, meat, poultry and seafood.
Vegan dieters avoid all foods derived from animals. Vegans do not eat meat, poultry, seafood, eggs or dairy foods. They also avoid food products containing gelatin -- an ingredient derived from animal collagen -- found in many gummy candies, marshmallows and gelatin desserts. Because vegan diets are the most restricted type of vegetarian diet, careful planning is necessary to ensure vegans meet their daily nutritional needs. Important nutrients for vegan dieters include vitamin D, vitamin B-12, calcium, iron, zinc and omega-3 fatty acids, according to the 2010 review in "Nutrition in Clinical Practice." Supplementation may be necessary in some cases to prevent deficiencies of these nutrients.
Disease Risk Considerations
In general, the fewer foods derived from animal-based products you eat, the lower your body mass index and chronic disease risks will be. The 2010 review in "Nutrition in Clinical Care" reports that vegetarians have lower rates of high blood cholesterol, high blood pressure, death from heart disease, stroke, type-2 diabetes and certain cancers than nonvegetarians. The 2009 study in "Diabetes Care" reports that body mass index is lowest in vegans, followed by lacto-ovo vegetarian and pescatarian dieters. Meat eaters had the highest BMI.