ATLANTA, Georgia (CNN) -- It's lunchtime at Café Sunflower in Atlanta, Georgia. The kitchen is humming as the chef prepares the most popular item on the menu: sesame chicken. That's not what you'd expect at a vegetarian restaurant. But the so-called chicken is actually a seasoned soy product made to taste like the real thing. "It's a treat for vegetarians who miss meat," says restaurant owner Edward Sun.
John Papazoglou is a lacto vegetarian, meaning he eats dairy products but no eggs.
John Papazoglou of Washington, D.C., is one of them. He made a special stop at the cafe while in town on business. A vegetarian for 15 years, he eats no meat, fish or eggs. He finds it difficult to maintain a healthy, satisfying diet while traveling. "Actually being a vegetarian doesn't guarantee good nutrition," he says. "You still have to have a balanced diet."
Papazoglou is among a growing number of people in the United States who've eliminated meat from their menus. The Vegetarian Resource Group estimates that 4.7 million adults are vegetarians.
They fall into several categories. Ovo lacto vegetarians don't eat meat, but consume eggs and dairy products. Ovo vegetarians eat eggs, but no dairy. Lacto vegetarians eat dairy, but no eggs. Vegans don't consume any animal products. Watch more on how vegetarians get a balanced diet. »
Katherine Tallmadge of the American Dietetic Association says to stay healthy, a vegetarian needs to eat a diet full of variety. Getting enough protein is one of the biggest concerns. "Protein is important for our immune system, our muscle mass and our bone mass," she says.
Ovo lacto vegetarians can get protein from eating eggs and dairy products such as cheese. Other protein-rich foods include legumes (beans, peas, lentils), nuts, seeds, whole grains and soy products.
Tallmadge also notes that a vegetarian can risk deficiencies in certain dietary minerals and vitamins, such as iron, calcium, vitamin D and vitamin B12, which is found only in animal products.
Vitamin B is found in green leafy vegetables, fortified cereals, grains and soy milk. Some experts recommend that vegetarians take a multivitamin to get enough B vitamins. Calcium can come through green leafy vegetables, including mustard and collard greens and broccoli. It's also found in soy milk and soy products. Iron-rich foods include dark green vegetables, dried fruits, nuts, seeds, whole grain and fortified breads, and cereals.
Registered dietitian Molly Paulson knows all about meeting daily nutritional requirements. Not only does she advise clients how to eat right, but her entire family is vegetarian, including a 3-year old daughter and 1-year-old twin boys. "I think it gives you a good, healthy feeling on the inside, a cleansing feeling because you're not weighed down with the saturated fats, the high-fat meals that make you feel fatigued," she says.
To satisfy a growing family, she shops for foods that are nutrient dense. "We do a lot of beans and brown rice," Paulson says. "I only give my family whole grains."
Paulson sees many new vegetarians gain weight because they make mistakes during meal planning. In an effort to feel full, she says, they "overconsume simple carbohydrates like white pasta and white bread."
She recommends that people do their homework before giving up meat. Taking a class, talking with a dietitian and collecting a few vegetarian cookbooks may be a good way to start.
She also suggests a daily vitamin supplement for those who may not be getting enough nutrients through meals. She cautions vegetarians to make sure the pills are made from non-animal sources. Gel-coated tablets, for instance, are often made from gelatin, which comes from animal products.
Reading the labels of soups and sauces is also important, according to Paulson, because the ingredients may include chicken or beef broth.
Shana Sheats, 30, another Café Sunflower customer, learned about vegetarian eating through trial and error. "You think you eat fruits and vegetables," Sheats says, "but there's more to it than that. It's nutrients, vitamins. It's a full-balanced approach."
Before she takes a bite of her stir-fried tofu with ginger, she has one more thought about vegetarian eating: "I feel great. I love it. I'd recommend it to anyone." E-mail to a friend
Judy Fortin is a correspondent with CNN Medical News.
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