University of Wisconsin - Extension

An emphasis on lowering dietary fat has caused increased interest in fish. However, some fish contain harmful levels of mercury that can be especially dangerous to developing fetuses and young children. Mercury can harm the developing brain and nervous system of young children.

But that doesn't mean that all pregnant and nursing mothers and young children must give up fish, says a University of Wisconsin-Extension food scientist.

"Pregnant and nursing women and young children should limit consumption of freshwater fish caught by family and friends to one meal per week," says Barbara Ingham. "For adults, one meal is six ounces of cooked fish. For a young child, one meal is two ounces of cooked fish."

In addition, she says many states collect data on mercury levels in fish from local waters. Check with your state or local health department for specific advice on lakes, streams and rivers where your family and friends fish.

The Food and Drug Administration has also issued advice on mercury in fish bought from stores and restaurants, which includes ocean and coastal fish, as well as other types of commercial fish.

FDA advises that women who are pregnant or could become pregnant, nursing mothers and young children not eat shark, swordfish, king mackerel, or tilefish. FDA also advises that women of childbearing age and pregnant women may eat an average of 12 ounces of fish from stores and restaurants per week.

"So, if you eat 12 ounces of cooked fish from a store or restaurant, then do not eat fish caught by your family or friends that week," Ingham says. "This is important to keep the total level of mercury at a low level in your body."

Ingham says other family members and older children do not need to be as concerned about the amount of freshwater fish they eat. The developing nervous system of a baby or young child is much more sensitive to the harmful effects of mercury than the more fully developed nervous system of an older child or adult. Other family members should follow the recommendations of the state or local health department on the amount of fish caught in local waters that is safe to eat.

For more information on freshwater fish advisories across the country, go to http://www.epa.gov/ost/fish/ and click on "Federal, State, and Tribal Contacts for Fish Advisories."

For more information on food safety issues, contact your local county Extension office.