By Lorri Holzberg

House Calls

Increasing numbers of Americans are turning to vegetarian diets - for health, humanitarian, religious and environmental reasons. When well planned, a vegetarian diet can be very healthy.

A vegetarian diet, based on whole grains, legumes, soy proteins, nuts, fruit and vegetables, is very likely to contain high levels of dietary fiber as well as adequate protein, vitamins, minerals and antioxidants - and low levels of saturated fats.

Benefits of a well-planned, low-saturated-fat vegetarian diet include a lowered risk for obesity, heart disease, hypertension, constipation, type 2 diabetes and gallstones. Not smoking, regular physical activity and adequate rest can enhance these benefits.

There’s a wide variation in food choices among vegetarians. Lacto-ovo-vegetarians eat milk products and eggs, while vegans exclude all forms of animal protein. Vegans in particular need to be careful about getting the appropriate nutrients.

Vegetarian diets can be very unhealthy if poor food choices are made - cheese, ice cream, whole milk, pastries and fast foods are rich sources of artery-clogging saturated fat. Adolescents are particularly susceptible to poor nutrition through poor food choices. Obviously, eating just salads and Oreo cookies is not a healthy diet.

Vegetarian diets take careful menu planning to be healthy. Vegan diets can offer adequate nutrition even for children, according to the American Dietetic Association, the Food and Drug Administration and the Institute of Food Technologists. A wider variety of vegan food choices provides a better chance of getting adequate nutrients. Protein, calcium, vitamin D, iron, riboflavin, zinc and vitamin B-12 are the nutrients of concern in a vegan diet.

Choosing legumes (beans and lentils), soy protein, whole grains, nuts and seeds regularly provides protein, calcium, iron and zinc. Dark green vegetables are a rich source of folic acid. Plant-based diets are rich in folic acid and vitamin B-6, which have recently been shown to be protective against heart disease.

Vitamin B-12, unfortunately, is present only in animal sources of protein. But multivitamin supplements and fortified cereals supply adequate amounts of it. Skin exposure to sunlight is a source of vitamin D.

The American Dietetic Association and other qualified health professionals make the following recommendations to ensure adequate nutrition from a vegetarian diet:

Choose a variety of foods, including whole grains, vegetables, fruit, legumes, soy proteins, nuts, seeds and, if desired, milk products and eggs.

Choose whole, unprocessed foods often and minimize intake of highly sweetened, fatty and heavily refined foods.

Choose a variety of seasonal fruit and vegetables.

Choose lower-fat versions of milk products and eggs, such as fat-free milk, lower-fat cheese and egg substitutes.

Lorri Holzberg is a registered dietitian at the El Camino Medical Group, a division of the Palo Alto Medical Foundation, in Sunnyvale. The Palo Alto Medical Foundation and column editor Arian Dasmalchi provide this monthly column.