Reaching for that can of tuna at the grocery store may not be the best idea, especially if you're pregnant.
A new study from Consumer Reports suggests that pregnant women should avoid all tuna, which is contrary to the FDA's determination that light canned tuna is "lower in mercury."
"Tuna happens to be one of the fish that can be very high in mercury, and some types of tuna have higher levels than others," said Jean Halloran, director of Food Policy Initiative. "The type that tends to get used in sushi is often very high, but even canned light tuna, which tends to average pretty low levels and is generally one of the safer fish to eat, occasionally has these spikes of high levels of mercury."
Since it is unsure what cans of tuna are safe to eat and what probably isn't, Consumer Reports suggests that pregnant women avoid them all together.
Tuna is one of the most commonly consumed seafood items in the country. The organization recommends limiting light tuna consumption to just under three cans of tuna a week.
"We're particularly concerned about canned tuna, which is second only to shrimp as the most commonly eaten seafood in the US," the report said. "Given its popularity and its mercury content, canned tuna accounts for 28 percent of Americans' exposure to mercury, according to an analysis by an EPA researcher published in 2007."
The FDA is poised to release some new guidelines about seafood consumption, but the new recommendations still list light canned tuna as low-mercury fish.
Seafood contains many proteins such as iron and omega-3 fatty acids. These nutrients are important for growth and brain development. However, seafood also has the potential to contain a neurotoxin called methylmercury that can cause severe birth defects.
Although pregnant women are especially at risk, eating too much seafood with high mercury levels is dangerous for everyone.
Consumer Reports also examined the other types of seafood found on the FDA's list of safer seafood.
The updated guidelines say that pregnant women and young children should avoid swordfish, shark, king mackerel and tilefish from the Gulf of Mexico to avoid high mercury levels. Marlin and orange roughy may also be added to that list.
