The agencies recommended that pregnant and breast-feeding women continue to limit their consumption of canned white tuna (usually referred to as albacore) to six ounces per week. Other cuts of tuna, including those most commonly found in canned form, need not be restricted.
The two agencies' joint announcement Tuesday marked the first time that federal officials have offered a recommendation setting a minimum level of fish consumption for better health. It was prompted by concerns that pregnant women and nursing mothers have been avoiding fish out of concern that it might prove harmful to their developing babies.
An FDA analysis of U.S. seafood consumption revealed that more than one fifth of pregnant women have consumed no fish in the past month, and that even those who do eat fish are consuming far less than would be beneficial to them and the babies they carry.
"For years, many women have limited or avoided eating fish during pregnancy or feeding fish to their young children," said Dr. Stephen Ostroff, the FDA's acting chief scientist. "But emerging science now tells us that limiting or avoiding fish during pregnancy and early childhood can mean missing out on important nutrients that can have a positive impact on growth and development as well as on general health."
The FDA recommended that pregnant women eat at least eight ounces and as many as 12 ounces of fish weekly (the equivalent of two to three servings). When consuming fish caught in local rivers, lakes or streams, the agencies urged women to follow fish advisories issued by local authorities. Where none are available, they recommended that pregnant women limit their weekly consumption of such fish to six ounces, and limit children's consumption to one to three ounces.
The new guidelines come against the backdrop of growing evidence for the health benefits of omega-3 fatty acids on developing brains and bodies. Epidemiological studies as well as clinical trials have demonstrated the value of the eicosapentaenoic acid (EPA), a polyunsaturated fatty acid that is plentiful in fish, for preserving cardiovascular health, and of docosahexaenoic acid (DHA) for fostering healthy brain development and preserving cognitive health.
Research evidence on these fatty acids' benefits has, however, been inconsistent. Still, positive studies have touched off aggressive efforts to market infant formulas and baby food supplemented with the omega-3 fatty acid known by its chemical name, docosahexaenoic acid (DHA).
The FDA's recommendations, however, are notable for their silence on the value of supplementation, and their endorsement of women and children's consumption of fish as a means of supplying omega-3 fatty acids.
"Fish as a whole food still seems better than supplementation," said Dr. Laura Jana, an Omaha, Neb., pediatrician and author of two books on nutrition published by the
Jana, who has worked with the National Fisheries Institute, said "something went terribly wrong" when the message of mercury in fish began to drive down fish consumption in pregnant women.