Types of vegetarian diets

When people think about a vegetarian diet, they typically think about a diet that doesn't include meat, poultry or fish. But vegetarian diets vary in what foods they include and exclude:

• Lacto-vegetarian diets exclude meat, fish, poultry and eggs, as well as foods that contain them. Dairy products, such as milk, cheese, yogurt and butter, are included.
• Ovo-vegetarian diets exclude meat, poultry, seafood and dairy products, but allow eggs.
• Lacto-ovo vegetarian diets exclude meat, fish and poultry, but allow dairy products and eggs.
• Pescatarian diets exclude meat and poultry, dairy, and eggs, but allow fish.
• Vegan diets exclude meat, poultry, fish, eggs and dairy products — and foods that contain these products.

Some people follow a semivegetarian diet — also called a flexitarian diet — which is primarily a plant-based diet but includes meat, dairy, eggs, poultry and fish on occasion or in small quantities.