There are several degrees of vegetarianism you may wish to follow. Like most things, vegetarian is a catch all phrase to describe a wide variety of people. The strictest form of vegetarian is vegan. Vegans do not eat any meat or animal byproducts. This means they do not eat dairy, eggs, or gelatin. They focus on a lot of soy-based foods, along with fruits, vegetables, nuts and seeds.
Plain vegetarians eliminate meat from their diet. They do not eat chicken, beef, pork, seafood, and most do not eat fish. They can, however, eat dairy and eggs. A red meat vegetarian does not eat beef or pork, but still enjoys chicken, turkey and fish. There are raw foods vegetarians, who do not eat any meat or food, which has been cooked. Their diet is based on raw fruits, vegetables, seeds, and nuts.
There are also people who call themselves fruititarians. They base their diet around fruits. They do not eat meat, dairy, or vegetables. This type of diet is generally not recommended by the medical community. There are also people who call themselves flexitarians. Their diet is 80% or higher vegetarian, but they do occasionally enjoy meat. Their diet allows them to follow a vegetarian diet without the strict rules or pressure of feeling they can never have meat if they are craving it. They recognize that sometimes your body craves specific things.
In general, following a vegetarian diet is very healthy. You are avoiding the animal fats present in meats. The problem comes in when vegetarians base their diet around pastas, and non-meat processed foods. Eating cheese pizza and breadsticks all the time, although vegetarian, is not very healthy. It is important o focus on the health aspects of a vegetarian lifestyle. Being vegetarian can also save money. In most cases, fresh produce is less expensive than meat at the grocery store.