The federal government is urging pregnant women, those who may become pregnant, breastfeeding mothers and young children to eat more fish – but also to be careful not to take in too much mercury.

The U.S. Food and Drug Administration and the Environmental Protection Agency issued an advisory this week recommending more fish because it will help with overall growth of the fetus during pregnancy and with young children.

The American Heart Association also recommends fish as part of a healthy overall diet, and AHA volunteer Judith Wylie-Rosett, Ed.D. applauded the move.

“Because of Omega-3 fatty acids, fish is essential to the development and growth of children,” said Wylie-Rosett, a professor of epidemiology and population and division head for health promotion and nutrition research at Albert Einstein College of Medicine in New York.

Fish is generally high in Omega-3 fatty acids, which decrease the risk of heart disease, the nation’s No.1 killer. The fatty acids also decrease triglyceride levels, slow the growth of atherosclerotic plaque and slightly lower blood pressure.

The FDA, EPA, and American Heart Association recommend eating a variety of fish and to have at least 2 servings of fish per week for adults. A variety limits mercury intake and provides a good source of protein. Fish is also generally low in saturated fat.

The AHA recommends fish known as “fatty” or “oily” fish because they are high in two kinds of Omega-3 fatty acids that reduce risks for heart disease, eicosapentaenoic acid and docosahexaenoic acid. Examples of this kind of fish include salmon, tuna, mackerel, herring, lake trout, sardines and albacore tuna.

Although all fish take in mercury, eating a variety will help guarantee that most fish you eat will be lower in mercury, the government advisory issued Tuesday said. Most fish found in grocery stores are lower in mercury.

The advisory also said there four types that should be avoided due to the high levels of methylmercury, a form of mercury: Tilefish from the Gulf of Mexico, shark, swordfish and king mackerel. (These four types of fish typically are not available in most grocery stores.)

The FDA and EPA suggest that no more than 6 ounces of the 8-12 ounces per week recommendation should be from white or albacore tuna because it has more mercury than canned light tuna.

If you go fishing in a lake, stream, or river, the FDA and EPA recommend to follow the local fish advisories.  If they are not listed, then eat 6 ounces or less of the locally caught fish per week and children should have no more than 1 to 3 ounces of the locally caught fish per week, according to the advisory.