With constantly changing opinions on what foods are the healthiest, and what foods we should be avoiding, there are new diets emerging on a regular basis. From fad diets, to weight-loss plans, to entire lifestyle changes, it can be hard to keep track of which is which. Even three of the longest-standing, most common, and most well-known diets are continuously confused with each other. Everyone knows at least one vegetarian (a term used for over 150 years), a vegan, or a pescatarian, but do we all know what those terms really mean?

Knowing the difference is important for two major reasons:

The first reason is that calling one diet (or lifestyle) the wrong term is just that. Wrong. 

The second reason is that confusing someone's dietary restrictions could be dangerous. If a vegetarian is fed fish because a cook/friend/chef assumes incorrectly that vegetarians eat fish, that person could become sick, especially if there is an allergy involved. 

Vegan

Vegans don't consume any animal (mammal, bird, fish, etc.) flesh or products, or any products made by animals (like eggs, dairy, and honey), or any products in general that directly lead to the exploitation, injury, or death of any creatures. Living a vegan lifestyle also includes not wearing or using animal products, like leather or fur. "Vegan" is a more recent (still over a half-century old) term for "strict vegetarian".

Vegetarian

Vegetarians don't consume any animal flesh, but may or may not consume various products made by animals (like eggs, dairy, and honey). Although many vegetarians choose not to wear or use animal products, a vegetarian lifestyle is less strict than vegan, and some vegetarians choose to use certain products like leather boots or hand-made drums made from "by-products" (e.g. skin) of the meat industry. Some vegetarians choose to categorize their diet as lacto-, ovo-, or lacto-ovo-vegetarians if they eat dairy or eggs, respectively, but the term "vegetarian" has generally come to include being open to eating both dairy and eggs, and usually doesn't need to be further categorized. 

Pescatarian

The most recently (but still a couple decades old) defined of the three, pescatarians have a diet similar to the vegetarian diet, but also include eating aquatic animals. The distinction between "vegetarian" and "pescatarian" is important to make, but being the newest, is also the most often confused (or ignored), frequently by pescatarians themselves. Pescatarians eat fish and other sea food, but do not eat any other animal (mammal. bird, etc) flesh.

Although these popular plant-based diets can appear restrictive, what they do include are fresh vegetables from leafy greens to tuberous roots, grains, nuts, seeds, fruits and berries, and beans: a food list with an infinite number of combinations and flavors.