By Joan Salge Blake , MS , RD, LDN

Nutrition professor at Boston University and a nationally known writer, lecturer and nutrition expert  

Vegetarianism

If you think that a vegetarian diet is a "one size fits all" strict eating plan, you'll be interested to learn that there are many styles of vegetarianism. In fact, it is likely that one style could satisfy the vegetarian yen in just about anyone, even if it is only at a single meal.

Vegetarian Diets

In the purest sense, a vegetarian diet is a plant-based diet that not only shuns all sources of meat, poultry and fish but also any foods derived from animals. There are, however, many varieties on this theme.

What can you eat?

As a vegetarian, fill your plate with a variety of grains, fruits and vegetables and use low fat and nonfat milk, yogurt, cheese and other dairy foods. To avoid falling short of important nutrients in your diet, include a variety of the following food options in your diet daily

Protein

Soy burgers and other "veggie" meats, soy milk, tofu, soy cheese, low fat milk, yogurt and cheese, nuts and soy nuts, peanut butter, eggs and egg whites

Iron

Enriched grains, pasta, rice and breads, iron-fortified ready-to-eat cereals and "veggie" meats, oatmeal, barley, nuts, sunflower seeds, legumes (dried peas and beans, such as black, kidney and navy beans and chick peas), whole wheat bread, blackstrap molasses, tomato juice, broccoli, and dried fruits such as apricots, currants, figs, raisins and prunes.

Zinc

Soy milk, tofu, fortified soy burgers, soybeans, cooked or dry roasted, fortified "veggie" meats, legumes, nuts and seeds, wheat germ and fortified ready-to-eat cereals

Vitamin B12

Eggs and low fat or nonfat dairy foods. Fortified foods such as ready-to-eat cereals, soy milk and soy burgers. Note: Check the Nutrition Fact Panel on the food product's label to ensure that vitamin B12 has been added. A vitamin supplement is also an option.

Calcium

Low fat or nonfat dairy foods, calcium fortified soy milk and orange juice or other calcium-fortified foods, tofu made with calcium, broccoli, bok choy, okra, kale, mustard greens, almonds and a calcium supplement

Vitamin D

Low fat or nonfat milk, fortified soy milk, soy yogurt, regular yogurt and ready-to-eat cereals. A vitamin supplement is also a reliable source.

Vitamin A

Fortified low fat or nonfat milk, deep orange and leafy green vegetables and fruits, such as pumpkin, butternut squash, carrots, apricots, cantaloupes, spinach and kale

Omega-3-Fatty Acids

Fish, especially fatty fish, such as salmon and sardines, walnuts, ground flaxseeds, tofu, soybeans, and soybean, canola, flaxseed and walnut oils

Benefits & limitations of Vegetarian Diets

The Pros

When it comes to fighting many chronic diseases, a vegetarian diet can provide potent dietary ammunition. Numerous research studies have shown that a diet rich in plant foods, specifically, whole grains, fruits, vegetables, nuts, and legumes, such as dried peas and beans — the staples of a vegetarian diet — can help lower the risk of obesity, heart disease, high blood pressure, a specific type of diabetes, and certain cancers.

For those interested in maintaining a healthy weight, vegetarian diets can be kind to your waist, as the satiety-provoking whole grains, fruits, and vegetables tend to "fill you up before they fill you out". In other words, the fiber in these plant foods, and in the case of the fruits and vegetables, their high water, yet low calorie content, enables you to feel full or satiated long before you are likely to over consume an excessive amount of calories. A dinner plate piled high with a variety of vegetables ladled on top of a bed of brown rice and black beans may leave little room in your stomach for a second helping, and more importantly, for you to overindulge on the brownie a la mode that follows the meal.

When it comes to your heart health, plant foods tend to be extremely low in artery-clogging saturated fat. Dietary saturated fat is the biggest culprit in raising your blood cholesterol level. A high blood cholesterol level is a risk factor for heart disease. Since dietary cholesterol is found ONLY in animal foods, vegans have the unique opportunity to enjoy diets that are 100 percent dietary cholesterol-free. This is a plus for your health as dietary cholesterol can also raise your blood cholesterol level. Whole grains, fruits, and vegetables are also rich in antioxidants, such as vitamins C and E, and beta-carotene, which also provide an extra heart-protective bonus.

Vegetarians, in general, tend to have a lower incidence of high blood pressure than non-vegetarians. An elevated blood pressure level can not only increase the risk for heart disease but also stroke. High fiber, plant-based diets have also been shown to reduce the risk of type 2 diabetes, the most prevalent type of diabetes mellitus in the United States . Unfortunately, diabetes is also a risk factor for heart disease.

Lastly, since plant-based diets have been shown to reduce the risk of both colon and prostate cancer, it's not surprising that the American Cancer Society has advocated a diet rich in whole grains, fruits, and vegetables. The high fiber content, rich source of phytochemicals (plant chemicals), and the abundance of antioxidants found in plant foods are all thought to play a cancer-fighting role.

The Cons

While a vegetarian diet may help prevent many chronic diseases, an unhealthy vegetarian diet can create a different set of medical problems. A daily diet of only rice and vegetables may be "vegetarian" but far from a healthy and balanced diet. When meat, fish, poultry, dairy foods, and eggs are missing in the diet, several important nutrients could also be missing in action. All vegetarians need to make sure that they are consuming adequate amounts of protein, iron, zinc, and vitamin B12, calcium, and vitamins A and D. Vegetarians who include dairy foods in their diet need to avoid loading their plates with saturated-fat laden, full-fat dairy foods such as whole milk and cheeses. Even though fatty meats may be limited on a vegetarian diet, a steady diet of fatty dairy products could cause the amount of artery-clogging saturated fat that is consumed to be off the Richter scale. Also, a vegetarian diet isn't guaranteed to keep you svelte if it is a predominately junk food vegetarian diet that is loaded with high calorie cookies, cakes, candy, and sweetened drinks.