Not too long ago, it was extremely difficult to live a vegetarian or vegan lifestyle. Much of it seemed to fly in the face of eating habits ingrained for a lifetime, along with concerns about vegetarian dining neglecting important parts of health and nutrition. But time has shown that vegetarian and vegan eating can be healthy, delicious lifestyles.

Definitions of vegetarianism tend to vary from person-to-person but it usually consists of a diet with no meat and very few animal products.

Vegetarians fall into groups defined by the types of animal-derived foods they eat:

• Vegans eat only plant-based foods.
• Lacto-vegetarians consume milk and milk products along with plant-based foods.
• Lacto-ovo vegetarians eat eggs, milk and milk products, such as cheese and yogurt, in addition to plant-based foods.
• Flexitarians (semi-vegetarians) primarily follow a plant-based diet but occasionally eat small amounts of meat, poultry or fish.

A healthy vegetarian diet consists primarily of plant-based foods, such as fruits, vegetables, whole grains, legumes, nuts and seeds. Because the emphasis is on non-animal based food sources, a vegetarian diet generally contains less fat and cholesterol, and typically includes more fiber.

Here are nutrients that may be deficient in a vegetarian diet and how you can get these nutrients from non-animal based sources:

• Protein. Your body needs protein to maintain healthy skin, bones, muscles and organs. Vegetarians who eat eggs or dairy products have convenient sources of protein. Other sources of protein include soy products, meat substitutes, legumes, lentils, nuts, seeds and whole grains.
• Calcium. This mineral helps build and maintain strong teeth and bones. Low-fat dairy foods and dark green vegetables, such as spinach, turnip and collard greens, kale, and broccoli, are good sources of calcium. Tofu enriched with calcium and fortified dairy-free milks and fruit juices are other options.
• Vitamin B-12. Your body needs vitamin B-12 to produce red blood cells and prevent anemia. This vitamin is found almost exclusively in animal products, including milk, eggs and cheese. Vegans can get vitamin B-12 from some enriched cereals, fortified soy products or by taking a supplement that contains this vitamin.
• Iron. Like vitamin B-12, iron is a crucial component of red blood cells. Dried beans and peas, lentils, enriched cereals, whole-grain products, dark leafy green vegetables, and dried fruit are good sources of iron. To help increase absorption of plant sources of iron, eat foods rich in vitamin C — such as strawberries, citrus fruits, tomatoes, cabbage and broccoli — at the same time you consume iron-containing foods.
• Zinc. This mineral is an essential component of many enzymes and plays a role in cell division and in the formation of proteins. Good sources of zinc include quinoa, beans, chickpeas and lentils, soy products, walnuts, cashews and chia, hemp and pumpkin seeds.

The key to a healthy vegetarian diet — or any diet for that matter — is to enjoy a wide variety of foods. Since no single food provides all of the nutrients that your body needs, eating a wide variety helps ensure that you get the necessary nutrients and other substances that promote good health.