Mercury in Fish: High-Mercury Fish to Limit & Low-Mercury Alternatives

Fish is a healthy and delicious food packed with essential nutrients, but some types contain high levels of mercury, a heavy metal that can pose health risks. This article will guide you through the basics of mercury in fish, providing information on high-mercury fish to limit and low-mercury alternatives to enjoy.

What is Mercury?

Mercury is a naturally occurring heavy metal found in the environment. Methylmercury, a type of mercury found in fish, is the primary concern for human health. It is absorbed by aquatic plants and then accumulates in fish, especially larger, predatory species.

Why Do Fish Contain Mercury?

Mercury enters the ocean through natural processes and human activities. Once in the water, bacteria convert it into methylmercury, a more toxic form. This methylmercury is absorbed by algae and other aquatic plants. Fish consume these plants, absorbing and retaining the mercury. Larger fish that eat smaller fish accumulate even higher levels of mercury through a process called biomagnification.

Health Risks of Mercury

Exposure to mercury, even at low levels, can pose health risks, especially for developing fetuses, young children, and pregnant women. High levels of mercury can damage the brain and nervous system.

Potential Health Effects of Mercury:

• Brain problems: Impaired fine motor skills, coordination, memory, and attention.
• Neurological conditions: Increased risk of conditions like Alzheimer's disease, Parkinson's disease, autism, anxiety, and depression.
• Cardiovascular issues: High blood pressure, increased risk of heart attacks, and high levels of 'bad' cholesterol.

High-Mercury Fish to Limit

The amount of mercury in fish is measured in parts per million (ppm). The following fish species are known to have higher mercury levels:

High-Mercury Fish:

1. Swordfish: 0.995 ppm
2. Shark: 0.979 ppm
3. King Mackerel: 0.730 ppm
4. Big Eye Tuna: 0.689 ppm
5. Marlin: 0.485 ppm

Choosing Low-Mercury Fish:

While limiting high-mercury fish is essential, you can still enjoy the benefits of fish as part of a healthy diet. Opt for these low-mercury alternatives:

Low-Mercury Fish:

1. Tuna (canned): 0.128 ppm
2. Cod: 0.111 ppm
3. Whitefish: 0.089 ppm
4. Herring: 0.084 ppm
5. Hake: 0.079 ppm
6. Trout: 0.071 ppm
7. Haddock: 0.055 ppm
8. Whiting: 0.051 ppm
9. Atlantic Mackerel: 0.050 ppm
10. Pollock: 0.031 ppm

Tips for Reducing Mercury Exposure

In addition to choosing low-mercury fish, follow these tips to further minimize your exposure to mercury:

• Limit your intake of high-mercury fish: Pregnant women, nursing mothers, and young children should consume high-mercury fish no more than once per week.
• Eat a variety of fish: Rotate your fish choices to avoid consuming high-mercury fish too frequently.
• Check seafood advisories: Your local government may issue advisories about mercury levels in specific fish species in your area.

Conclusion

By making informed choices about the types of fish you consume, you can enjoy the health benefits of this nutrient-rich food while minimizing the risks of mercury exposure. Be mindful of mercury levels in fish, especially if you are pregnant, nursing, or have young children.