What Fish Is Low In Mercury? A Comprehensive Guide

December 27, 2025 •

2 min read

According to the FDA, nearly all fish contain traces of mercury, a neurotoxin that can accumulate in the body over time. Understanding what fish is low in mercury is essential for safely enjoying seafood's many nutritional benefits, including heart-healthy omega-3 fatty acids. This guide offers clarity on which fish to choose and which to limit.

Quick Summary

This article details which fish species and shellfish are lowest in mercury, providing guidance on safe consumption for all populations. It explains how mercury bioaccumulates in the food chain and contrasts low-mercury options with high-mercury species. The content also highlights the significant health benefits of incorporating seafood into your diet.

Key Points

Prioritize Low-Mercury Species: The safest fish for consumption are those lower on the food chain, such as salmon, sardines, shrimp, and tilapia.
Avoid Large Predators: High-mercury fish like shark, swordfish, king mackerel, and certain tunas should be avoided, especially by pregnant women and children.
Canned Tuna Differences: Canned light tuna is a low-mercury choice, while canned or fresh albacore and bigeye tuna contain higher levels.
Farmed vs. Wild Mercury: Farmed fish generally contain lower mercury levels than their wild counterparts, but other factors should also be considered.
Follow FDA Recommendations: For optimal health, the FDA/EPA advises adults to eat 2-3 servings of low-mercury fish per week, with specific limits for pregnant women and children.
Mercury is Not Removed by Cooking: Since mercury is bound to the fish's flesh, cooking methods do not decrease its concentration.
Local Fish Advisories: Always check with local health departments for advisories regarding fish caught in local rivers, lakes, and coastal areas.

Understanding Mercury in Seafood

Mercury is a naturally occurring element that enters the environment through natural processes and human activities. In water, it's converted to methylmercury, which accumulates in aquatic life through a process called bioaccumulation. Larger, predatory fish higher up the food chain tend to have higher mercury levels than smaller fish. Cooking does not remove mercury, so choosing low-mercury species is key to reducing exposure.

Best Low-Mercury Fish and Shellfish Choices

The FDA and EPA identify "Best Choices" for fish consumption, particularly for pregnant women, breastfeeding mothers, and young children, due to their low mercury content. These can be eaten multiple times per week. Some of the best low-mercury options include Salmon, Sardines, Shrimp, Tilapia, Catfish, Cod, Pollock, Clams, Oysters, Scallops, Freshwater Trout, and Canned Light Tuna.

Fish to Limit or Avoid

Certain large, predatory fish have high mercury levels and should be limited or avoided, especially for sensitive groups. The FDA lists some as "Choices to Avoid," such as Shark, Swordfish, King Mackerel, Bigeye Tuna, Orange Roughy, Marlin, and Tilefish from the Gulf of Mexico.

Mercury Levels in Farmed vs. Wild Fish

Generally, farmed fish tend to have lower average mercury levels than wild fish. However, choosing low-mercury species is often considered more critical for mercury avoidance than the farmed versus wild distinction.

The Health Benefits of Eating Low-Mercury Fish

Low-mercury fish provide valuable nutrients like lean protein, vitamins D and B2, minerals, and omega-3 fatty acids. Omega-3s are known to support heart health, brain function, and reduce inflammation.

Comparison Table: Low vs. High Mercury Fish


Feature	Low-Mercury Fish	High-Mercury Fish
Examples	Salmon, Sardines, Shrimp, Tilapia, Cod, Canned Light Tuna	Shark, Swordfish, King Mackerel, Bigeye Tuna, Orange Roughy, Gulf of Mexico Tilefish
Position in Food Chain	Lower; eat smaller prey like plankton and insects	Higher; large predators that eat smaller fish
Life Span	Generally shorter	Generally longer, allowing more time for mercury to accumulate
Safe Consumption (FDA/EPA)	2-3 servings (8-12 oz) per week recommended	Avoid completely, especially for pregnant women and children
Nutritional Profile	Excellent source of omega-3s, lean protein, vitamins	Also contains nutrients, but high mercury risk outweighs benefits for sensitive groups

How to Make Smart Choices

Making safe fish choices involves prioritizing low-mercury species and being aware of those to limit. Following guidelines from the FDA/EPA and checking local advisories are key steps.

Conclusion

Incorporating fish into your diet offers significant health advantages. By opting for low-mercury fish such as salmon, sardines, and tilapia, you can enjoy these benefits safely. It's crucial to avoid species known for high mercury content, like shark and swordfish, and to consider specific advice regarding tuna and local fish. Making informed decisions about seafood is vital for a healthy diet and lifestyle. More information can be found on {Link: FDA website https://www.fda.gov/food/consumers/advice-about-eating-fish}.

Frequently Asked Questions

Sardines and scallops are among the fish with the absolute lowest mercury levels, according to FDA data. Other very low-mercury options include anchovies, shrimp, and tilapia.

Yes, it is safe and encouraged for pregnant women to eat fish. The FDA and EPA recommend that pregnant women consume 8 to 12 ounces per week of a variety of fish from their 'Best Choices' list, which includes species low in mercury.

Canned light tuna, which is usually skipjack, has lower mercury levels than canned or fresh albacore ('white') tuna. The FDA recommends limiting albacore tuna intake to 6 ounces per week for sensitive populations.

Larger, older fish tend to have more mercury due to bioaccumulation. As they eat smaller fish over a longer lifespan, the mercury absorbed by their prey accumulates and becomes more concentrated in their own bodies.

You should always check for advisories from local, state, or tribal health departments before eating fish caught from local waters, as mercury levels can vary significantly. If no advisory exists, limit consumption to one serving per week.

Studies generally show that farmed fish have lower mercury concentrations than their wild counterparts, primarily because of their controlled diet and shorter lifecycles.

Low-mercury fish are an excellent source of protein, vitamins D and B2, and essential minerals. They are also packed with beneficial omega-3 fatty acids, which support heart and brain health and reduce inflammation.

No, freezing fish does not reduce its mercury content. The mercury is permanently bound to the protein in the fish's flesh.