Carolyn O'Neil, co-author of the book "The Dish on Eating Healthy and Being Fabulous!" said a well-planned vegetarian diet can be healthful and nutritious but vegetarians need to pay particular attention to protein, iron, calcium, zinc and vitamin B12 in their diets -- nutrients most get from meat.
About 5 percent of U.S. adults call themselves vegetarians, and while they don't eat meat, they need protein and milk is high-quality protein -- milk has even more protein than an egg.
As a result vegetarians drink about 30 percent more milk than non-vegetarians, and get an extra 150 milligrams calcium in their diets, on average. In addition, milk provides key nutrients such as phosphorus and B vitamins.
"There's really just no substitute for milk -- especially in a vegetarian diet," O'Neil said in a statement. "It delivers more nutrition per penny than just about any other drink."