Tuna Warning

For years, government officials have warned of the harmful affects caused by eating fish containing large amounts of mercury. Now, for the first time, the FDA is including the popular tuna on that list.

The Early Show medical correspondent Dr. Emily Senay will give the facts on Friday about the new warning about tuna.

A FDA food advisory committee held meetings this week, looking into the harmful effects of mercury contained in tuna. While the government has warned the public of the danger from mercury found in other fish in the past, consumer advocates have sought for years to alert people to the possible risks from tuna. A draft advisory from the committee is now cautioning certain groups of women to limit their tuna intake, and formal guidelines are expected by early next year.

Senay says the people who should be most concerned are women of child bearing age, specifically those who are pregnant, thinking of becoming pregnant, nursing mothers, or young children.

Mercury is a neurotoxin, and exposure to high levels can lead to damage in the brain and nervous systems of both fetuses and young children. Ailments related to such damage could span from learning and attention disabilities to potentially causing something as drastic as mental retardation. Senay says it's a very serious issue that the government is addressing.

Currently, the FDA is advising those who are at risk to limit their tuna consumption, along with other kinds fish and shellfish to twelve ounces a week, or approximately three modest meals. Most tuna bought is in cans, sold in approximately 6-ounce portions. Recent FDA tests suggest that canned albacore, or white tuna contains nearly three-times as much mercury as canned "light" tuna.

Over 80 percent of all tuna sold is used in lunch meat - and is served with school lunches. Up until recently, tuna was the most widely consumed seafood in the country. Senay says if you or your children fall into this category, you really want to watch what you're putting in your mouth. The panel is also suggesting not to eat the same fish more than once in the same week.

It's not known exactly how much tuna eaten is unsafe, but, as Senay explains, the tuna industry wants a government advisory informing people of possible dangers. As the guidelines are currently written, the FDA will not be warning women of child bearing age to avoid tuna altogether, but it does warn them to be mindful of consumption.

The FDA has suggested women of child bearing age and children to avoid eating the following fish: