Why I care about pregnancy and fish

I took particular interest in the recent U.S. scandal involving a seafood industry front group recommending that pregnant women eat more fish, despite existing concerns about high mercury levels in some species. Why? First, because I’ve been writing about seafood for Worldwatch for many years. Second, because my wife is just a few short weeks from giving birth to our first child.

The row began when the National Healthy Mothers, Healthy Babies Coalition departed from conventional wisdom that pregnant women eat no more than 12 ounces of fish a week, recommending instead that they eat at least 12 ounces a week. Subsequent reporting revealed that the National Fisheries Institute, a seafood trade association, had paid the group several tens of thousands of dollars to publicize these findings. Adding to the uproar is the fact that prominent members of the coalition, including the American Academy of Pediatrics, the March of Dimes, and the U.S. Centers for Disease Control and Prevention, don’t agree with the revised recommendation—and didn’t even know it was being announced. (The New York Times' Marion Burros added some more details.)

It's true that some studies have found that children whose mothers regularly ate fish during pregnancy and who themselves ate fish regularly after being born scored higher on early development exams, presumably because the omega-3 fatty acids and other essential nutrients in the fish encouraged neurological function. But as Gerald Leape, vice president of marine conservation for the National Environmental Trust, noted in a response to these findings, "It's misleading to urge pregnant women to eat more fish without mentioning the documented public health risks associated with fish or how consuming more seafood is diminishing the world's fisheries stocks.” In addition to the heavy metals and contaminants often found in larger wild fish, and which can damage developing brains, Leape noted that farmed fish often contain antibiotics, colorants, and pesticides, several of which are known carcinogens.

The good news is that there are plenty of other sources of omega-3 fatty acids, including eggs, flax, nuts, and kiwi fruits. And there are plenty of types of seafood that yield the same brain-nurturing boost without the mercury risk. I checked out the nifty mercury calculator provided by the Turtle Island Restoration Network and found out that my wife could eat 2 pounds of flounder, nearly 3 pounds of anchovies, or 7 pounds of oysters before reaching her safe mercury level. In contrast, just 2 ounces of bigeye tuna would land her in the red zone. Eating 7 pounds of oysters (about 280 oysters) is a contest-winning proposition, and my wife would be able to get her weekly quota of omega-3s from a just a few dozen. And she’d only have to eat 11 ounces of pickled herring compared with twice as much canned tuna.

So, during my wife’s pregnancy, we’ve been steering clear of big fish, like tuna or swordfish, which happen to be the highest in mercury and also the most overfished. We’ve been favoring low-on-the-food-chain—and abundant—species like clams, anchovies, sardines, porgies, and flounder. We live near the coast of Long Island, New York, where I can regularly go clamming and oystering, and where friends and family are constantly offering us fresh fish. My father, a lifelong fisherman who recently found that his blood mercury concentrations were six times the recommended levels, has been eating less of the big fish himself, and he’s been giving us fillets of snappers—one-year-old bluefish that haven’t had a chance to accumulate the mercury that their older brethren carry.

Still, I’ve learned over the last nine months that pregnancies are anything but predictable. Eating habits, in particular, become quirky. My wife, a long-time vegetarian, has developed a reputation as a formidable pork eater. Eggs—from a farm stand around the corner—have also become a new fixture in her diet. And even though we have access to incredibly fresh seafood that is low in mercury and high in omega-3s, and we know how healthy fish can be, when we’re planning dinner, she admits she just doesn’t have a flavor for fish. And that’s the main reason she doesn’t eat more fish during her pregnancy.