Diet / Nutrition

How Much Fish Should Children And Pregnant Women Eat?

It's been known for many years that mercury can harm the developing nervous system of the fetus and young child, so it's particularly important that this toxin is avoided by pregnant or nursing women and by children. It's also been known that mercury can be present in certain kind of fish, and a number of warnings over the years have discouraged children and pregnant women from eating too much mercury-containing fish. What's been less clear is how much mercury is harmful, how much is in different kinds of fish, and how much fish can be eaten safely.

Now, both the U.S. Food and Drug Administration and Environmental Protection Agency have issued new recommendations. Both agencies point out that pregnant women and children can safely eat up to 12 ounces of fish each week, as long as they avoid shark, swordfish, king mackerel, and tilefish, which all contain relatively high concentrations of mercury. No more than 6 ounces should come from canned albacore ("white") tuna (canned light tuna has less mercury than albacore). Alternative choices would include shrimp, salmon, Pollock, or catfish. Fresh tuna steaks fall into the same category as albacore tuna, and also should be limited to 6 ounces. Fish sticks and most fast-food fish sandwiches are low in mercury.

The recommendation for tuna was the most controversial, with some critics arguing that amounts should be reduced further. FDA acknowledged that following the new tuna recommendation would push the level in a pregnant or nursing woman's blood above the level that been identified by EPA as posing "no risk", but Dr. David Acheson of the FDA noted that "If you're a little above the reference zone, you're not in a zone of harm." He argued that "Fish is good to eat. It's high in protein, low in saturated fat, and it's a very important part of a balanced diet. We have to balance the good side of fish with any risks from mercury." (Dembner A: Boston Globe, March 8, 2004)

COMMENT: For years, the FDA and EPA have each issued different recommendations about how much fish is safe to eat, so the fact that both agencies are in agreement should end some of the confusion. On the other hand, this is a very complicated area, and parents and others should recognize that there are few absolute guidelines to follow. First, the problem with any of these recommendations is that it's very difficult to really know how much they actually affect a child's development-for example, it's not entirely clear just how much mercury is required to harm a child's brain development. Also, fish get their mercury from their immediate environment, and levels of contamination can vary in different locations, so it's hard to know just how much mercury will be in different species caught in different regions.