Image courtesy of Women's Health

You might want to think twice about feasting on seafood. A whopping 84 percent of fish samples taken from around the world contain unsafe levels of mercury, according to a new report from the Biodiversity Research Institute and the International Persistent Organic Pollutants Elimination Network. It isn't safe to eat fish with such high levels of mercury more than once a month, according to the findings.

And that's not all. Researchers also took hair samples from 152 people from around the world. What they found: More than 82 percent contained mercury levels greater than the U.S. Environmental Protection Agency's recommended level. Translation: People are exposed to more mercury than is good for them.

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So what's the big deal? Consuming mercury can affect your nervous system and your brain, and this can be especially dangerous for children and women who are pregnant, according to Lisa Moskovitz, RD, CDN, CPT, owner of Manhattan-based practice Your New York Dietician. "Mercury acts like a neurotoxin which, even in low doses, can impair a baby's development and cognitive function. In some cases it can lead to mental retardation, cerebral palsy, and loss of sight and hearing," she says. "In non-pregnant adults, mercury affects fertility, blood pressure, memory, and eyesight."

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Pretty scary stuff, but that doesn't necessarily mean you need to cut fish out of your diet altogether. "Because fish is an important nutrient source, it's more about being smart with what you are eating versus avoiding eating fish," says David Evers, Ph.D., chief scientist of the Biodiversity Research Institute who specializes in research on ecotoxicology. He suggests consulting your doctor and checking out the EPA's recommendations to lower your risk.

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Here, excerpted from the EPA's website, three guidelines for reducing your exposure to mercury found in fish:

1. Do not eat shark, swordfish, king mackerel, or tilefish because they contain high levels of mercury.

2. Eat up to 12 ounces (2 average meals) a week of a variety of fish and shellfish that are lower in mercury.

Five of the most commonly eaten fish that are low in mercury are shrimp, canned light tuna, salmon, pollock, and catfish.Another commonly eaten fish, albacore ("white") tuna has more mercury than canned light tuna. So, when choosing your two meals of fish and shellfish, you may eat up to 6 ounces (one average meal) of albacore tuna per week.

3. Check local advisories about the safety of fish caught by family and friends in your local lakes, rivers, and coastal areas. If no advice is available, eat up to 6 ounces (one average meal) per week of fish you catch from local waters, but don't consume any other fish during that week.

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