Vegan vs. Vegetarian: What's the Difference?

Vegetarians avoid meat, poultry, and fish but may choose to eat animal byproducts like eggs and dairy. Most vegetarian diets focus on eating fruits, vegetables, grains, nuts, and seeds.

Some individuals choose to be vegetarians for health reasons and/or to increase awareness about animal cruelty and slaughter for food.

Types of vegetarian diets include:

• Lacto-ovo vegetarian: Lacto comes from the word lactose, a Latin term for milk, whereas ovo comes the word egg. A lacto-ovo vegetarian does not eat meat, poultry, or shellfish but will eat dairy, eggs, and honey. This is the most common and widely practiced type of vegetarianism.
• Lacto vegetarian: A lacto-vegetarian does not eat meat, poultry, shellfish, or eggs but will eat dairy products including milk, cheese, yogurt, and butter.
• Ovo vegetarian: An ovo vegetarian does not eat meat, poultry, fish, or dairy but may eat eggs.

Diets that are often mistaken for vegetarian include:

• Flexitarian: A flexitarian is someone who eats predominantly vegetarian but rarely or infrequently consumes meat and other animal products. This diet provides flexibility for people who want to eat mostly plant-based foods but are reluctant to give up meat completely.
• Pescatarian: A pescatarian diet is largely plant-based. However, it does incorporate seafood, such as fish, as a protein source. Pescatarians may or may not consume eggs and dairy products. A pescatarian diet is great for people who enjoy seafood and do not want to forego the nutritional benefits.
• Pollotarian: A pollotarian is someone who eats a plant-based diet as well as poultry such as chicken and turkey. Like pescatarians, they may or may not include dairy and eggs in their diet.
• Pesco-pollo vegetarian: A pesco-pollo vegetarian is someone who eats a plant-based diet but also eats fish and chicken, just not red meat.

Vegans follow a strict form of vegetarianism that eliminates all animal-based foods (meat, poultry, game, fish, shellfish, eggs, dairy products) and animal derivatives (gelatin, carmine, honey, pepsin, shellac, albumin, whey, casein, some forms of vitamin D). Vegans often need to take supplements to avoid nutritional deficiencies. 

Vegans often choose to avoid all animal by-products for ethical and environmental reasons in addition to health reasons. They may even avoid wearing materials and textiles such as leather, suede, wool, and silk.

According to the Journal of the American Dietetic Association, a well-planned vegan or vegetarian diet can be nutritious and may aid in the prevention and treatment of certain diseases. 

However, avoiding particular foods entirely can be nutritionally dangerous unless care is taken to satisfy nutritional requirements. Vegan and vegetarian diets often lack the following nutrients:

• Vitamin B12 (seldom found in plant-based foods but is essential for the nervous system and heart)
• Vitamin B6
• Niacin
• Zinc 
• Omega-3 fatty acids

Even though most vegetarian and vegan diets are nutrient-dense, care should also be taken to avoid highly processed, high-fat, high-sugar foods.

Vegan and vegetarian diets can both have health benefits as long as the diet is well-planned and balanced.

Vegetarians may consume slightly higher amounts of calcium, phosphorus, and vitamin D than vegans. Vegans may have lower cholesterol levels than vegetarians because they avoid dairy and eggs. In terms of weight reduction, a study reported that vegans had a lower body mass index than vegetarians. Over a 5-year span, vegans gained less weight than vegetarians. 

While there are only a few research studies that look at the distinctions between veganism and vegetarianism, data suggests that vegan diets are more protective as well as restrictive. According to a meta-analysis published in Critical Reviews in Food Science and Nutrition, vegans may have a lower risk of developing certain diseases than vegetarians, including heart disease, type II diabetes, and some types of cancer.

Whichever diet you choose, make sure you analyze your daily nutrient intake and consider supplements if necessary.