Is eating fish healthy or unhealthy?: Balancing the Benefits and Risks

October 22, 2025 •

4 min read

According to the American Heart Association, consuming fish at least twice a week is part of a healthy diet. But with concerns about contaminants and farming practices, many people still wonder, is eating fish healthy or unhealthy? The answer is complex, balancing powerful nutritional benefits against potential environmental risks.

Quick Summary

Eating fish is beneficial due to its high-quality protein, vitamins, and omega-3 fatty acids, which support heart and brain health. However, potential risks from contaminants like mercury and PCBs, particularly in certain species, must be considered. Making informed choices about fish type, source, and preparation can maximize health advantages while minimizing hazards.

Key Points

Rich in Omega-3s: Oily fish like salmon and mackerel are packed with omega-3 fatty acids (EPA and DHA), essential for heart and brain health.
Source of Key Nutrients: Fish provides high-quality protein, vitamins (D, B12), and minerals (iodine, selenium) that support overall health.
Mercury is a Risk: Larger, predatory fish (shark, swordfish) contain higher mercury levels and should be limited, especially by vulnerable groups like pregnant women and young children.
Consider PCBs and Toxins: Environmental pollutants like PCBs can accumulate in fish fat; minimizing fat consumption and choosing lower-risk species helps reduce exposure.
Wild vs. Farmed Depends: Both can be healthy, but differ in nutrient profile, contaminant levels, and environmental impact; research sourcing practices for responsible choices.
Cook Fish Thoroughly: Properly cooking seafood to 145°F kills harmful bacteria and parasites, mitigating the risk of foodborne illness.
Choose Variety and Sourcing: Diversifying the types of fish you eat and choosing sustainably sourced options are key for a healthy and safe diet.

The Case for Healthy Fish Consumption

Fish and shellfish are a cornerstone of many healthy diets, celebrated for their unique nutritional profile. Health organizations worldwide recommend regular consumption to reap the numerous benefits, which far outweigh the risks for most people.

Heart and Brain Health

The primary appeal of fish lies in its rich content of omega-3 fatty acids, specifically eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These essential fatty acids are crucial for human health, as the body cannot produce them in sufficient quantities. Fatty fish like salmon, mackerel, and sardines are particularly abundant sources.

Omega-3s are linked to a host of cardiovascular benefits, including:

Lowering triglyceride levels in the blood.
Reducing the risk of sudden cardiac death, heart attack, and stroke.
Slowing the buildup of plaque in arteries.
Slightly lowering blood pressure.

Beyond heart health, these fatty acids are vital for brain function and development, with evidence suggesting a potential role in reducing the risk of cognitive decline, Alzheimer's disease, and depression. Adequate DHA intake during pregnancy is especially important for a baby's brain and nervous system development.

Rich Source of Essential Nutrients

Fish is also a superb source of high-quality, easily digestible protein, containing all the essential amino acids needed for muscle and organ health. It provides a wealth of other vital nutrients, including:

Vitamin D: Crucial for bone health and immune function.
Vitamin B12: Supports nerve function and red blood cell formation.
Iodine: Essential for proper thyroid function.
Selenium: A powerful antioxidant that protects cells from damage.
Iron: Supports blood health and oxygen transport throughout the body.

Potential Risks and How to Mitigate Them

Despite the significant benefits, concerns about contaminants are valid and require attention. Harmful chemicals can accumulate in fish from the water they live and feed in.

Mercury Contamination

One of the most publicized risks is mercury, which is found naturally in the environment and accumulates in fish over time. Larger, longer-lived predatory fish tend to have the highest levels of mercury.

High levels of mercury can be harmful to the nervous system, especially for developing fetuses, infants, and young children. To minimize exposure, health authorities advise at-risk groups to limit or avoid certain high-mercury species. For the general population, eating a variety of fish with low mercury levels is recommended.

PCBs and Other Environmental Toxins

Polychlorinated biphenyls (PCBs) and dioxins are persistent organic pollutants that can accumulate in fish fat. Exposure to high levels of these chemicals has been linked to health issues, though the risks from the much lower levels found in most fish today are generally considered low. PCBs bind to fat, so discarding skin and fat and using cooking methods like broiling or grilling that allow fat to drain can help reduce exposure.

Raw Fish and Foodborne Illness

Eating raw or undercooked fish, as in sushi or ceviche, carries a risk of bacteria (e.g., Vibrio) or parasites. The risk is low with proper handling, but freezing the fish first can kill most parasites. High-risk individuals, including pregnant women, young children, and those with compromised immune systems, should avoid raw seafood. Always source raw seafood from trusted suppliers known for high food safety standards.

Wild-Caught vs. Farmed Fish

The choice between wild-caught and farmed fish introduces additional considerations regarding nutritional value, contaminants, and environmental impact.


Feature	Wild-Caught Fish	Farmed Fish
Diet	Natural diet of other marine life, varying with season and location.	Controlled diet, often including grain, soy, and fishmeal.
Omega-3s	Often have a more balanced omega-3 to omega-6 ratio.	May contain higher total omega-3s, but also more overall fat and omega-6s, depending on feed.
Contaminants	Levels can vary widely by species and location, but generally lower in PCBs.	Confined conditions can sometimes lead to higher levels of contaminants like PCBs due to feed or water conditions.
Antibiotics	Do not receive antibiotics.	Can be treated with antibiotics and pesticides to combat disease in crowded conditions.
Sustainability	Risk of overfishing; look for certifications like MSC.	Practices vary widely; look for certifications like ASC or recommendations from groups like Seafood Watch.

Making Healthy and Safe Choices

Here are some practical tips to maximize the benefits and minimize the risks of eating fish:

Choose a variety of fish: This helps balance your nutrient intake and minimize exposure to any single type of contaminant.
Prioritize low-mercury options: Excellent choices include salmon, sardines, trout, shrimp, and canned light tuna.
Cook it safely: Thoroughly cook seafood to an internal temperature of 145°F (63°C) to kill harmful bacteria and parasites.
Use healthy cooking methods: Grilling, baking, or broiling are preferable to deep-frying, which can increase overall fat content.
Consider sourcing: Look for sustainably sourced seafood certified by organizations like the Marine Stewardship Council (MSC) or Aquaculture Stewardship Council (ASC), or use resources like Seafood Watch.

Conclusion: A Balanced Perspective

Ultimately, for the vast majority of people, the answer to is eating fish healthy or unhealthy? is overwhelmingly positive. The robust evidence supporting fish's benefits for heart, brain, and overall nutritional health is compelling. By following guidelines on safe consumption, choosing low-mercury and sustainably sourced options, and preparing fish properly, you can enjoy this versatile and nutritious food with confidence. Fish is not a foe to be avoided but a friend to be understood and consumed wisely as part of a balanced diet.

For more detailed information and specific recommendations, consult the U.S. Food and Drug Administration's (FDA) Advice about Eating Fish.

Frequently Asked Questions

For most adults, health organizations like the American Heart Association recommend eating at least two servings of fish per week, with one being an oily variety.

Fatty, cold-water fish are the best sources of omega-3s. Excellent options include salmon, mackerel, tuna (especially albacore), trout, herring, and sardines.

Canned tuna and salmon are convenient and affordable sources of high-quality protein, vitamins, and minerals. However, canned fish, particularly canned tuna, may have different mercury and omega-3 levels than fresh, depending on the species.

Yes, it is safe and encouraged for pregnant women to eat fish, but they should choose low-mercury options and limit total intake to 8-12 ounces per week. Recommended choices include salmon, shrimp, and canned light tuna, while high-mercury fish like shark and swordfish should be avoided.

Farmed fish can sometimes have higher levels of PCBs compared to wild-caught fish, though this depends heavily on farming practices. However, both types can contain environmental contaminants like mercury, making informed choices and diverse intake important.

The safest option is to cook fish thoroughly. If you choose to eat raw fish, select sushi-grade fish that has been commercially frozen to kill parasites and bacteria. Pregnant women, young children, and immunocompromised individuals should avoid all raw seafood.

While both are nutritious, wild fish may have a better omega-3 to omega-6 balance and contain less overall fat. Farmed fish can have higher total fat and omega-3 content, but this is influenced by their controlled diet.

Opt for healthier cooking methods like baking, grilling, broiling, or steaming, as these do not add extra fat. Frying can increase fat content and potentially introduce other contaminants.