Great Job Avoiding Mercury in Seafood, but Americans Aren't Eating Enough Fish

Fears about the toxic metal may have driven consumers away from healthy fare.
Nov 26, 2013· 2 MIN READ
Clare Leschin-Hoar's stories on seafood and food politics have appeared in Scientific American, Eating Well and elsewhere.

It’s not easy being pregnant. Moms-to-be are told fish high in omega-3 fatty acids are some of the best things they can eat for their baby’s brain development. But knowing which fish are best can be confusing. Critics say government warnings to steer clear of fish that contain higher levels of mercury have muddled the message for nearly a decade, leaving women scratching their heads over how to successfully balance the advice.

But it turns out, women are doing pretty well at avoiding the heavy metal—too well, maybe.

A study released earlier this month by the U.S. Environmental Protection Agency shows women of childbearing age are heeding warnings about mercury in seafood, and it found that blood mercury levels dropped 34 percent from 2000 to 2010.

“The news is very gratifying,” says Dr. Michael Gochfeld, professor of environmental toxicology at the Robert Wood Johnson Medical School. “It’s what we’ve been advocating—you don’t have to stop eating fish over mercury concerns.”

Gochfeld says the change could stem from the availability of more low-mercury seafood options.

“There’s more tilapia on the market than there used to be, and shrimp is the number one seafood, and it’s low in mercury,” he says.

While it’s good news that blood mercury concentrations are declining in women of childbearing age, we found another part of the report confusing. The EPA says “there was very little change in the amount of fish consumed”, but that doesn’t jive with other consumption data available.

In 2010, Dietary Guidelines Advisory Committee whose recommendations impact the USDA’s food pyramid confirmed that Americans were not eating enough seafood. Earlier that year, the Food and Agriculture Organization of the United Nations and the World Health Organization urged governments (including ours) to do a better job communicating the health benefits of eating seafood.

And the National Fisheries Institute, which tracks U.S. seafood consumption, shows numbers trending downward: In 2004, Americans ate 16.6 pounds of seafood a year. In 2012, that number dropped to 14.2 pounds a year.

“The volume of seafood [being eaten] is and has been going down for all populations,” said Gavin Gibbons, NFI spokesman. “The fact is, pregnant women still only eat 1.89 ounces of seafood, and that’s nothing to celebrate when U.S. dietary guidelines recommend they eat at least 8 ounces, more than four times what they do now."

The government message about the importance of seafood during pregnancy, mercury and all, is just not getting through to women, Gibbons added.

"The benefits outweigh the risks. That’s the message they need to be hearing because it’s accurate and promotes healthy fetal development," he said.

Some critics say the decline in seafood consumption is directly related to the 2004 joint EPA-FDA advisory on mercury consumption and seafood. Many consumers embraced the warning, not just the target audience of women of childbearing age, pregnant and nursing women, and young children. And unlike the USDA food pyramid, which is updated every five years, the seafood advisory hasn’t been revised in almost a decade.

In 2009, the FDA published a risk and benefit assessment of seafood consumption, but no action has been taken to revise the advisory.

“The assessment of net effects of fish consumption during pregnancy and the updated advice remain a priority for the administration, and we hope to issue them as soon as possible,” said FDA spokesman Sebastian Cianci.

The EPA didn’t get back to us regarding the discrepancy in consumption rates, but its report did include news of other actions. The agency says it's taking significant action toward making fish and shellfish safer to eat. In June it proposed new effluent guidelines for steam electric plants, which are a source of mercury discharges. And in April, the agency issued the new Mercury and Air Toxics rule, which sets emissions limits.

So where does that leave eaters? Gochfeld’s advice is clear: “If you eat fish once a month, you can eat anything. If you eat fish rarely, your health would benefit from eating fish once a week. If you’re eating fish three times a week or every day, then be attentive to the mercury contents.”

And if you’re pregnant, that 2004 advisory still applies: Avoid any high mercury fish, such as shark, swordfish, king mackerel, or tilefish.

Sardines, by the way, are delicious, and aren't a mercury concern.