A lacto vegetarian is a person who eats vegetable products, grain, and dairy products, but who avoids any type of consumption of animal flesh, including fish. What sets this form of vegetarian apart is that he usually doesn’t eat eggs, unless he is describing himself incorrectly. Those vegetarians who add eggs to their diet are more accurately described as lacto-ovo or lacto-ova vegetarians, and the strict lacto vegetarian is very different because of egg consumption avoidance.
Culturally, there are groups who have practiced longstanding lacto vegetarianism. This form of dietary practice is particularly common in certain parts of India. Some of the ancient Greeks who followed the teachings of Pythagoras were also said to have adopted a lacto vegetarian lifestyle. Their beliefs additionally include avoidance of any types of beans, and having dairy products in the diet would have been greatly useful because these provide good protein.
Today there are still parts of India where a lacto vegetarian diet is common, and the diet has influenced some vegetarians around the globe. Some people argue that eating eggs supports farming practices that are cruel, but this isn’t always the case. Given a little land and permission from town or city officials, people can raise their own poultry in a manner that seems perfectly kind and simply collect eggs as they’re laid, since they are almost waste products of the hens.
The lacto vegetarian may not avoid eggs because they are a comment on cruelty of chicken rearing. Some people with this diet don’t eat eggs because they have allergies, don’t care for eggs or because they’re trying to avoid high cholesterol foods in their diets. It should be noted that some dairy products can be high in cholesterol too, and the person looking to keep cholesterol low may need to avoid butter or high fat cheeses.
Label reading is another important part of remaining a lacto vegetarian. There are a number of commercially produced dairy products that contain animal byproducts. Many cheeses have rennet, which is removed from cows’ or sheep's stomachs, and is technically meat. Gelatin is another animal product, which shows up in many dairy offerings, especially things like puddings and yogurts.
Eggs, of course, are hidden ingredients in a variety of baked goods. There are substitutes for things like gelatin and rennet, but these may be a little hard to find. People should look for vegetarian rennet or gelatin but the meat byproduct use can limit selection of foods, particularly of cheese.
Lacto-ovo and lacto vegetarian diets are contrasted to the vegan diet where virtually all meats and animal byproducts are avoided. Each diet has benefits and challenges. The vegan diet is lacking in vitamin B12 and some attention needs to be paid to supplementation with this vitamin. Lacto-ovo and lacto vegetarians get some vitamin B12 though milk and eggs or just milk, but they may need to consider taking a supplement or eating cereals that are supplemented with the vitamin in order to get enough.