Pregnant women should stop eating all forms of tuna, even the canned light variety, due to risks of mercury exposure, says Consumer Reports.
The Yonkers, N.Y.-based organization's new report, "The Great Fish Debate," which appears in the October issue of the magazine — and is currently available online at www.consumerreports.org — is based on its own analysis of the FDA's data on mercury in fish, said Dr. Michael Crupain, Consumer Reports' associate director of consumer safety and sustainability.
According to the March of Dimes, babies who are exposed to mercury in the womb can have brain damage, vision and hearing problems.
Consumer Reports' recommendations go against the latest guidelines from the FDA and the EPA on how much tuna pregnant women can eat safely. In June, the government agencies issued a federal proposal encouraging women who are pregnant, breastfeeding or trying to become pregnant to eat between 8 and 12 ounces of seafood per week — and kept light canned tuna on their list of lower-mercury fish.
But light tuna is not a good choice, said Crupain, due to a strong likelihood that it may contain high levels of mercury. "We just don't think it's necessary for pregnant women to take any risks."
For some doctors, Consumer Reports' new advisory is creating a quandary: Should they stick to the federal guidelines and continue to tell their pregnant patients it's OK to eat a little light tuna each week? Or should they reinforce the importance of fish and seafood to the developing fetus — but make sure their patients know of the new warnings?
"The concern is that patients are going to see this and avoid all fish products, and then they won't have the benefit of getting the Omega-3 fatty acids, which have been proven to help with the neurologic development of the fetus,'' said Dr. Denis Sconzo of Westchester Bronx Ob/Gyn in Yonkers.
"Seafood is a great source of lean protein and essential fatty acids for pregnant women," said Dr. Patricia Pollio, director of OB/GYN at Good Samaritan Regional Medical Center in Suffern. "I have always counseled my patients to avoid tuna steaks, shark and swordfish due to high levels of mercury, and have recommended up to two three-ounce servings per week of chunk light, not solid white, tuna. I will now have to counsel my patients that eating tuna is controversial."
Consumer Reports' advisory extends to all forms of tuna, including yellowfin and big-eye tuna, also known as "ahi," often used in sushi. Tests found that many samples had as much mercury as shark and swordfish, which the FDA urges pregnant women to avoid.
Canned light tuna contains about a third the amount of mercury of albacore tuna — often labeled in cans as solid white or chunk white — said Crupain. But neither is a good choice during pregnancy.
"Our main concern with canned tuna, canned light tuna especially, is that about 20 percent of the data collected since 2005 by the FDA had levels of mercury in the tuna that were twice what the average is, so the probability of encountering some of those much higher levels of mercury is pretty high,'' he said.
Consumer Reports analyzed FDA data on mercury levels in fish released in 2011, and used EPA guidelines to calculate the safe amount for people to eat, said Crupain. "Tuna is not on the list of low-mercury fish that we created because if you do the math, it ends up being above where we set the threshold for being a really low mercury fish."
The FDA, however, however, is standing by its recommendations, citing the health benefits of fish and seafood for pregnant women, young children and those who are breastfeeding.
"The advice is based on new science indicating that eating more fish can have important growth and developmental benefits, and that these benefits can outweigh the risk of methylmercury exposure,'' said FDA spokeswoman Lauren Sucher in an email.
The FDA currently has a list online, featuring the mercury content of commercial fish and shellfish. The agency welcomes comments on the issue, said Sucher, and will review all commentary received.
"The Consumer Reports analysis is limited, in that it focuses exclusively on the mercury levels in fish without considering the known positive nutritional benefits attributed to fish,'' added Sucher, who said the way the organization did its research overestimated fish's negative effects and overlooked a "strong body" of recent scientific evidence.
But Crupain said Consumer Reports is not discounting the importance of fish in the diet.
Its report includes a list of 18 low-mercury fish that are good choices, including wild and Alaska salmon, shrimp, sardines, tilapia, scallops and oysters.
"What we're saying is we agree with the FDA that people, especially pregnant women and children, should eat fish, and we think their recommendations of how much fish to eat are good,'' he said. "We just think that when they eat fish, they should choose fish with the lowest mercury — but they don't tell them what the low-mercury fish are. They kind of leave it up to the public to figure it out themselves."
"We think they should be giving consumers better advice about what low-mercury fish are, and that's what we've done."