We both LOVE canned tuna. It hits the trifecta for taste, convenience, and a quick source of protein. It also boasts a modest to high amount of omega-3s.
To clarify, there are two main kinds of canned tuna: chunk light and solid or chunk white (albacore). Though most canned white tuna is albacore, it’s mercury levels are almost three times higher than the smaller skipjack tuna, used in most canned light varieties. Most are aware that pregnant and nursing moms are told to avoid or strictly limit certain fish (including tuna) for this reason. But should it be a concern for the average consumer?
Excess mercury can damage nerves, leading to memory loss, irritability and balance problems. According to the FDA, it is safe to get, on average, up to 7 micrograms (mcg) of mercury a week for every 22 pounds you weigh. That averages out to about 50 mcg for a 150 pound person (our preference would be lower than that if possible). Four ounces of canned albacore (white) tuna has an average of 40 mcg of mercury. For comparison, an equivalent amount of canned light tuna has only 13 mcg.
To avoid any risk of toxicity, women who are pregnant, nursing, or could become pregnant, as well as children under 55 pounds, are advised not to eat albacore tuna at all. Those women should limit their intake to light tuna, and only about 2 ounces per week (1 oz. for children). Most other adults can safely eat up to 3 oz. of albacore tuna or 12 oz. of light tuna a week. However, we don’t believe in pushing the limits on this. That being said, if you have any concerns, talk to your doctor about what serving size might be right for you. It can depend on many factors including weight, age, and health condition.
Because we are also concerned about the environment and waste, we always choose brands that catch their tuna by trolls, polls, or FAD-free purse seines (FAD stands for fish aggregating devices, which attract, catch and waste a lot of other fish unnecessarily). Unfortunately, many popular brands do use these fishing methods, including Chicken of the Sea, Starkist, and Bumblebee.
In addition, the troll/poll catching tends to catch younger tuna which have lower mercury accumulation – so it is a win-win in buying from these sources.
Here’s the good news: most local supermarkets are now carrying sustainable brands. Look for the words poll or troll caught on the label. Here is a list of some of our favorites.
- Wild Planet
- Natural Sea
- Safe Catch* – (they actually test every fish for mercury content and from our research their skipjack is the lowest mercury tuna available)
- American Tuna* This brand was formed by 6 local fishing families in San Diego. Their albacore is tested annually and has been found to be on average .236 ppm (parts per million) – way less than the FDA safety level of 1 ppm (parts per million) or even the lower European standard of .5 ppm.
What about sushi?
Sushi fans, listen up. A survey by Rutgers University found that people who eat sushi weekly—particularly types that are higher in mercury like tuna—are at risk for excessive mercury poisoning. To boot, a report by the University of Michigan reveals that the mercury concentrations in Hawaiian yellowfin tuna (also known as ahi tuna, a popular fish for rolls and sashimi) are increasing by 3.8 percent or more per year. For this reason, we suggest sushi-lovers opt for lower-mercury rolls like eel, crab, salmon, or kelp.
Let’s wrap up by saying that mercury in tuna is a real concern. For health and environmental reasons, keep your intake limited to suggested portions above, choose wisely at sushi restaurants, and shop for sustainable low mercury brands.