WASHINGTON (AP) – The heart-healthy benefits of eating fish overshadow any risk posed by mercury or other dangerous contaminants, the Institute of Medicine reported Tuesday.

Still, consumers are perplexed and need help figuring out which fish and shellfish they should eat, according to the institute, which advises the government on health policy.

“The confusion may have scared people out of eating something that is beneficial for them and maybe for their offspring,” said Jose Ordovas, a Tufts University researcher and member of the report committee.

“Our goal was to put both things in perspective and see where is the balance,” Ordovas said.

Findings from the institute are in line with widely accepted government advice that eating fish and shellfish may reduce people’s risk of developing heart disease, the leading cause of death in the United States.

Similar conclusions are being reported in Wednesday’s Journal of the American Medical Association.

That study concluded thousands more deaths from heart disease could result annually from avoiding fish because of confusion about the risks and benefits. Heart disease is the leading cause of death for adults in the United States.

Interestingly, the institute said it’s unclear how eating fish fights heart disease. It may be that beneficial omega-3 fatty acids offer some protection. Or the answer may be simpler, that people eat less saturated fat and cholesterol when they choose leaner seafood instead of fatty cuts of meat.

Americans generally eat too much saturated fat and cholesterol and too little of the good omega-3 fatty acids, the report said. And evidence shows that eating seafood rich in omega-3s can contribute to vision and cognitive development in babies and help expectant moms carry babies to term, researchers said.

The Tuna Foundation and other industry groups issued a statement saying the report tells consumers not to let fears of mercury exposure stop them from enjoying the nutritional benefits of regular fish consumption.

Critics contend the report will only worsen confusion about which people should avoid which fish.

“The study hyped up the benefits of Omega 3s, but paid mere lip service to the threat of harmful contaminants found in both wild and farmed fish,” said Gerald Leape of the National Environmental Trust.

Environmental and consumer groups say it should have listed “good fish” and “bad fish,” which the researchers said would be too difficult.

Seafood is the main source of people’s exposure to methylmercury, which is linked to learning disabilities and developmental delays in children and to heart, nervous system and kidney damage in adults.

Critics were also alarmed the report offers similar guidance for pregnant women as well as young children.

“They seem to be unaware that children are smaller than adults,” said Jean Halloran, director of food safety at Consumers Union, which publishes Consumer Reports magazine. “That advice, which they have featured prominently, could result in young children getting excessive doses of mercury.”

For pregnant women and children younger than 12, the report said:

-They may benefit from eating seafood, especially seafood with higher amounts of omega-3 fatty acids.

-They may eat six to 12 ounces of seafood a week, including up to six ounces of albacore tuna. For children, a reasonable intake is two 3-ounce servings “or age-appropriate servings,” but they can safely eat 12 ounces a week.

-They should avoid big predatory fish such as shark, swordfish, tilefish or king mackerel, which have higher mercury levels.

For healthy teenagers and adults and those at risk of heart disease, the report said eating seafood may reduce the risk of heart disease. And if people eat more than two servings of seafood a week, they should be sure to eat different kinds of seafood to reduce the risk of exposure to contaminants, the report said.

While the report does not list “good” or “bad” fish, it does describe broad categories:

-Fatty fish like salmon have the highest omega-3 levels but also have more saturated fat and cholesterol and can have higher levels of dioxin and PCBs. They tend to have less mercury.

-Shellfish and crustaceans are low in saturated fat but can have moderate amounts of cholesterol and present the greatest risk of microbial infection if eaten raw.

-In all seafood, levels of dioxin, PCBs and other contaminants do not pose health risks when eaten in government-recommended amounts.