Vegetarian eating has become increasingly popular in recent years, and people may choose to eat this way because of ethical, environmental, religious, or health reasons.

A vegetarian diet emphasizes plant foods and includes some animal foods, so you may wonder if vegetarians eat fish or seafood.

This article provides an overview of whether you can eat fish on a vegetarian diet.

Vegetarians do not eat the flesh of animals. Thus, by this definition, fish and seafood are not vegetarian (1).

Some vegetarians, known as lacto-ovo-vegetarians, eat certain animal products, such as eggs, milk, and cheese. Still, they do not eat fish.

If vegetarians include fish and seafood in their diets but still avoid the flesh of other animals, they’re considered pescatarians.

However, whether pescatarians are labeled as such may be up to interpretation. Some people may still consider those who mostly eat a fully plant-based diet — with rare consumption of fish and seafood — vegetarians.

Those who follow other forms of predominantly plant-based eating patterns, such as the flexitarian or Mediterranean diet, may also eat fish and seafood (1).

Summary

Since fish and seafood are considered animal flesh, they’re not technically vegetarian. If someone eats these foods while otherwise following a vegetarian diet, they’re typically referred to as a pescatarian.

Pescatarians who choose to add fish to their vegetarian eating pattern may do so for many reasons.

Eating fish or seafood can add more variety to a diet and allow more options for protein sources at meals.

Some people may also eat fish for its health benefits.

Fish and seafood are rich in protein and provide numerous vitamins and minerals, including zinc and vitamin B12, which are vital for your immune and nervous systems. It can be difficult to get enough of these nutrients on a strict vegetarian diet (2, 3, 4).

For example, a single oyster provides 85% of the Daily Value (DV) for zinc and 78% of the DV for vitamin B12 (5).

Fish, especially salmon, herring, and sardines, is also the best dietary source of the omega-3 fatty acids eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). On the other hand, very few plant foods contain EPA and DHA (6).

These essential nutrients are important for proper fetal development and optimal brain and heart health throughout your life (7).

Certain plant foods provide the omega-3 alpha-linolenic acid (ALA), which your body can convert into EPA and DHA, but it’s not easily converted. Thus, some vegetarian diets may lack omega-3 fatty acids (8).

The variety of vital nutrients that fish and seafood provide may be one of the main reasons that pescatarians choose to incorporate them into their otherwise plant-based eating patterns.

Summary

Pescatarians may choose to add fish to their vegetarian diets for more variety, as well as the protein, micronutrients, and omega-3 fatty acids that fish and seafood contain.

Fish and seafood are not considered vegetarian.

However, a pescatarian diet is a primarily plant-based diet that incorporates fish and seafood.

People may choose to follow a pescatarian eating pattern instead of a strictly vegetarian one for more variety, as well as the nutritional benefits of fish.