Two new reports suggest the benefits of consuming fish outweigh the risks of environmental contamination from mercury poisoning.
The reports also address the confusion over the health risks and benefits of eating fish.
Harvard cardiologist Dariush Mozaffarian reviewed all available studies documenting the risks of mercury exposure through eating fish. His team also reviewed all studies showing the health benefits of fish consumption. He says the benefits of consuming fish still outweigh the risks.
"When we put all the evidence together [from clinical trials], we found that eating fish reduces the risk of dying from a heart attack by about 35 percent which is a dramatic benefit," he says.
Mozaffarian's paper, published in the Journal of the American Medical Association on Tuesday, suggests that the average consumer has little reason to worry.
"We didn't find any definite evidence that there are health effects of low-level mercury exposure from seafood intake for the general population," he says. "For the average person, we didn't find any health effects for mercury."
Mozaffarian says several studies were conducted in Europe where scientists analyzed whether higher mercury levels in the blood stream correlate to an increased risk of heart attacks.
"In those studies, some find that mercury is related to harm [while] some show a neutral effect, and some show trends toward [a] benefit -- where people with higher mercury levels actually had trends to lower risk of a heart attack," he says.
Given the lack of consistency in the findings, Mozaffarian says there seems to be no significant effect on eating fish for adults. Children, however, should still eat limited amounts of seafood. Several studies from New Zealand and the Faroe Islands suggest that higher levels of mercury exposure can negatively affect children's brain development.
The federal government also recommends that pregnant women and women of childbearing age avoid certain types of seafood that are known to contain high amounts of mercury.
The advice has created confusion for many consumers, particularly mothers-to-be. Jonathan Scher is a Professor of Obstetrics and Gynecology at Mount Sinai School of Medicine.
"Working with pregnant women, it's an immediate concern for them when they're deciding to get pregnant," says gynecologist Jonathan Scher. "What do I do about fish?"
Scher, who teaches obstetrics and gynecology at Mount Sinai School of Medicine in New York, says that women should keep eating fish, particularly species low in mercury.
The findings corroborate a second report released today, from the Institute of Medicine. The report concludes that omega-3 fatty acids in seafood contribute to vision and brain development in infants.
Panel Chairman Malden Nesheim says pregnant women should be advised about which species to avoid and how much is safe to eat.
"A reasonable amount would be 2- 3 ounce servings per week," he says "but they can safely consume up to 12 ounces per week."
The Institute of Medicine report concludes that the best way to end seafood-lovers' confusion is to consolidation information. The group Environmental Defense has developed a list that ranks fish species by mercury pollution.
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