What is it called when you only eat fish and vegetables? A Guide to Pescetarianism

December 10, 2025 •

3 min read

Coined in the early 1990s, the term for when you only eat fish and vegetables is 'pescetarianism,' a dietary pattern that combines the Italian word for fish ('pesce') with 'vegetarian'.

Quick Summary

Pescetarianism is a dietary choice centered on plant-based foods, supplemented with fish and other seafood. It involves abstaining from meat from land animals like beef, pork, and poultry.

Key Points

Name of the diet: Eating only fish and vegetables is known as pescetarianism, or pesco-vegetarianism.
Core components: The diet is primarily plant-based, with the inclusion of fish and other seafood, while excluding all other types of meat.
Health benefits: Pescetarianism offers significant health advantages, including improved heart health due to omega-3s, and a reduced risk of certain chronic diseases.
Nutritional advantage: The inclusion of fish provides high-quality protein, vitamin B12, and other key nutrients that can be more challenging to obtain on a strict vegetarian diet.
Important considerations: Potential drawbacks include mercury exposure and environmental concerns related to overfishing, both of which can be managed with careful seafood choices.
Flexibility: Pescetarianism is a flexible and varied diet, allowing for personal choice regarding eggs and dairy, and is often considered easier to follow long-term than a strict vegetarian diet.

Understanding the Pescetarian Diet

Pescetarianism, also known as pesco-vegetarianism, describes a diet primarily based on plants while including fish and other seafood. This dietary choice excludes all meat and poultry from land animals. Historically, similar dietary patterns have been followed in various cultures. It is often seen as a balanced approach, combining plant-based eating with the nutritional benefits of seafood.

What Pescetarians Eat and Avoid

A pescetarian diet emphasizes whole, unprocessed foods. While flexible, it consistently omits meat and poultry.

Foods Pescetarians Eat:

Fish and shellfish
Fruits and vegetables
Whole grains and legumes
Nuts, seeds, and healthy oils
Optional inclusion of dairy and eggs

Foods Pescetarians Do Not Eat:

Beef
Pork
Lamb
Chicken
Turkey
Other land animal meat

The Benefits of a Pescetarian Lifestyle

A pescetarian diet can offer notable health and environmental advantages.

Heart Health: Fatty fish provides omega-3 fatty acids essential for heart and brain function, potentially reducing heart disease risk, lowering blood pressure, and decreasing the chance of heart attacks and strokes.
Reduced Chronic Disease Risk: This diet is associated with lower risks of type 2 diabetes and metabolic syndrome, thanks to high plant intake and beneficial fats from fish.
Environmental Impact: Avoiding red meat and poultry can reduce one's environmental footprint, as fish and seafood generally have a lower impact on greenhouse gas emissions and land/water use.
Protein Source: Fish and shellfish offer high-quality protein, which can simplify meeting protein needs compared to strictly vegetarian or vegan diets.

Potential Drawbacks and Considerations

While beneficial, a pescetarian diet requires attention to potential issues.

Mercury Content: Certain large fish may contain higher mercury levels. Recommendations often suggest limiting or avoiding these, particularly for vulnerable groups, and choosing smaller, low-mercury options like salmon and sardines.
Sustainability: Concerns exist regarding overfishing and unsustainable practices. Choosing sustainably sourced seafood is important.
Nutrient Planning: Some pescetarians, especially those avoiding dairy and eggs, may need to ensure sufficient intake of nutrients like iron through plant sources and fortified foods.

Comparison Table: Pescetarianism vs. Vegetarianism vs. Veganism


Feature	Pescetarianism	Vegetarianism	Veganism
Excludes	Meat and poultry (land animals)	All meat, poultry, and fish	All animal products
Includes	Fish, seafood, plants, often dairy and eggs	Plants, often dairy and eggs	Only plant-based foods
Omega-3s (DHA/EPA)	Excellent source from fish	Requires supplements or specific foods	Requires supplements or specific foods
Vitamin B12	Easily obtained from fish, eggs, dairy	Careful planning, often fortified foods or supplements	Must come from fortified foods or supplements
Protein Sources	Fish, seafood, legumes, nuts, seeds, eggs, dairy	Legumes, nuts, seeds, eggs, dairy	Legumes, nuts, seeds, grains

Conclusion

Pescetarianism is a well-established and nutritious dietary approach. It provides a plant-forward diet supplemented with fish and seafood, offering health benefits and a potentially lower environmental impact than diets including red meat and poultry. By being mindful of potential issues like mercury and sustainability, a pescetarian diet can be a healthy and sustainable choice. More information can be found in the Harvard Health blog post: Thinking about becoming a pescatarian? What you should know about the pescatarian diet.

Frequently Asked Questions

A pescetarian eats a plant-based diet plus fish and seafood, whereas a vegetarian excludes all meat, fish, and poultry.

Some studies suggest a pescetarian diet offers additional benefits, particularly in providing essential nutrients like omega-3 fatty acids and vitamin B12 that may be lacking in some vegetarian diets.

Many pescetarians include eggs and dairy in their diet, but this is optional and depends on individual preferences. Some variants, like a strict pescetarian diet, exclude them.

Yes, many people find success with weight management on a pescetarian diet due to its focus on lean protein and fiber-rich foods, which help with satiety.

For lower mercury intake, it is best to focus on smaller fish like salmon, sardines, and canned light tuna. Larger, predatory fish such as shark and swordfish should be limited or avoided.

A pescetarian diet generally has a lower environmental impact than a meat-heavy diet, especially when focusing on sustainably sourced seafood to avoid issues like overfishing.

In addition to fish, common protein sources include legumes, nuts, seeds, tofu, eggs, and dairy, depending on individual preferences.