Is Salmon High in Mercury? What the Science Says

Recent data from the FDA reveals that salmon has a low mercury concentration, averaging only 0.022 parts per million (ppm). This makes salmon one of the safest seafood choices, suitable for frequent consumption by all, including pregnant women and children. Concerns about mercury are valid; however, the context of a balanced diet is important.

Quick Summary

This article explores the mercury content in salmon, highlighting its low levels. It explains why salmon is considered a safe option, contrasts wild and farmed varieties, and compares mercury concentrations with those found in other fish. No mention of guides or what the reader will learn.

Key Points

• Salmon is Low in Mercury: The FDA considers salmon a "Best Choice" due to its low mercury levels.

• Wild and Farmed Salmon are Safe: Both wild and farmed salmon have low mercury content.

• Diet and Lifespan Matter: Salmon doesn't accumulate high levels of methylmercury like larger, predatory fish.

• Nutritional Benefits Outweigh Risks: The low mercury levels and high omega-3 content make salmon a beneficial food.

• High-Mercury Fish to Avoid: Avoid large predatory species such as shark and swordfish.

• Safe for Vulnerable Groups: Regulatory bodies confirm salmon is safe for pregnant women and children.

Understanding Mercury in Seafood

Mercury is a naturally occurring element that enters the environment from sources like volcanic activity and human actions, such as burning fossil fuels. When mercury is in water, it changes into methylmercury, a neurotoxin that accumulates in fish and moves up the food chain. The concentration of methylmercury in fish depends on their diet, lifespan, and place in the food chain. Larger, older fish that eat other fish tend to have the highest levels of mercury.

Why Salmon's Mercury Levels Are Low

Unlike large predatory fish such as shark and swordfish, salmon are lower in the food chain and have shorter lifespans. They eat smaller organisms, which reduces the amount of mercury they accumulate. This is a primary reason why salmon, both wild and farmed, are considered safe by food safety experts. Its health benefits, including high levels of heart-healthy omega-3 fatty acids, are widely believed to outweigh any potential risks from low mercury levels.

Wild vs. Farmed Salmon: Is There a Difference?

Concerns existed that farmed salmon might have higher levels of contaminants compared to wild salmon. However, recent studies and changes in feed regulations have helped address these issues. Both farmed and wild salmon are considered safe and have low mercury levels. A 2025 study examining Atlantic salmon found that wild salmon sometimes had higher levels of mercury than farmed salmon, possibly due to more rapid growth in the farmed fish. The conclusion remains that both varieties are safe, with any differences falling within federal consumption guidelines.

Comparing Mercury Levels in Common Seafood

Comparing mercury levels is essential when choosing the safest seafood options. Salmon consistently ranks as one of the lowest-mercury fish. The FDA and EPA categorize seafood into 'Best Choices,' 'Good Choices,' and 'Choices to Avoid' based on their mercury content.

Fish Category	Examples	FDA Mercury Advice	Mean Mercury Content (PPM)*	Note
Best Choices	Salmon, Shrimp, Sardines, Tilapia	2-3 servings per week	0.01-0.02	Very low mercury, high in omega-3s
Good Choices	Albacore Tuna (Canned), Mahi Mahi, Cod	1 serving per week	0.1-0.35	Moderate mercury, moderate intake recommended
Choices to Avoid	King Mackerel, Swordfish, Shark	Avoid	>0.5	Highest mercury levels, should be avoided

*Based on data from the FDA.

Making Informed Seafood Choices

To maximize the benefits of seafood while minimizing mercury exposure, salmon remains a top recommendation. The omega-3 fatty acids (EPA and DHA) found in salmon are crucial for infant brain development and heart health in adults. For pregnant women, children, and those with health concerns, the FDA provides specific guidance on seafood consumption based on mercury levels. Eating a variety of low-mercury fish can further diversify nutrient intake and minimize risk. Experts generally agree that the nutritional benefits of eating salmon far outweigh any risks associated with its low mercury content.

How Mercury Accumulates

Methylmercury enters the food chain and accumulates in fish tissue over time, a process known as bioaccumulation. This is why older, larger predatory fish, which have eaten many smaller fish over their longer lifespans, have the highest mercury concentrations. Salmon's shorter lifespan and diet make it a low-risk option. The presence of selenium in some fish, including salmon, may also have a protective effect, as it can bind with mercury and reduce its toxicity.

Nutritional Benefits Beyond Mercury

Focusing solely on mercury can overshadow the considerable nutritional benefits of salmon. It is a rich source of high-quality protein, vitamins D and B12, and minerals like selenium. These nutrients are vital for various bodily functions, from bone health to neurological function. The omega-3s are particularly noteworthy for their anti-inflammatory properties and benefits to cardiovascular health.

Conclusion

In conclusion, salmon is not high in mercury. Scientific data from organizations like the FDA confirm that both wild and farmed salmon contain low levels of mercury, making them a safe and healthy addition to any diet. The fear of mercury in salmon is a misconception. Consumers can enjoy salmon regularly, knowing they are reaping significant nutritional benefits, especially from its omega-3 content, with minimal mercury risk. Prioritizing low-mercury seafood like salmon is a wise choice for a balanced and nutritious diet.

Tips for Safe Seafood Consumption

• Diversify your fish intake: Eat a variety of fish from the FDA's "Best Choices" list.
• Limit high-mercury fish: Minimize consumption of fish on the "Choices to Avoid" list.
• Follow local advisories: Check for local advisories for fish caught recreationally.
• Properly cook seafood: Ensure all seafood is cooked to the recommended temperature to avoid bacteria.
• Consider canned varieties: Canned light tuna and salmon are generally lower in mercury.

Is Salmon High in Mercury? What the Science Says

Visit the FDA's Advice About Eating Fish for more comprehensive guidelines on seafood safety and consumption recommendations.

Frequently Asked Questions

Is salmon safe to eat during pregnancy?

Yes, salmon is considered very safe for pregnant women. The FDA recommends it as a "Best Choice" seafood option due to its low mercury levels and high omega-3 fatty acid content, which is beneficial for fetal brain development.

Does canned salmon have mercury?

Yes, but in very low amounts. Canned salmon typically has even lower mercury levels than fresh or frozen salmon because smaller fish are often used for canning. The FDA lists it as a "Best Choice".

What is methylmercury and why is it a concern?

Methylmercury is a toxic form of mercury that accumulates in fish and can harm the human nervous system, particularly for developing fetuses and young children. However, salmon's low position in the food chain means it accumulates very little of this substance.

How does salmon compare to tuna regarding mercury?

Salmon has significantly lower mercury levels than most types of tuna. While canned light tuna is a "Best Choice" with moderate mercury, albacore tuna is a "Good Choice," and large predatory tuna like yellowfin and bigeye can have higher levels.

How often can you eat salmon?

Based on its low mercury content, you can safely enjoy salmon multiple times per week. The FDA advises up to 2-3 servings per week from the "Best Choices" category, which includes salmon.

Do wild and farmed salmon have different mercury levels?

While there can be slight variations, both wild and farmed salmon consistently have low mercury levels that fall well within federal safety guidelines. Some studies have found wild salmon to have slightly higher mercury, but both are considered safe.

What kind of fish should I avoid due to high mercury?

You should avoid or limit large, predatory fish such as shark, swordfish, king mackerel, marlin, and tilefish from the Gulf of Mexico, as these species have the highest levels of mercury.