A panel of scientists has asked the FDA to update its fish mercury level charts. The panel argues that current guidelines are misleading and can lead to high mercury intake from tuna.
While tuna has long been thought of as a "health food", it also contains mercury in it. Scientists estimate that a full 8% of women in childbearing years have enough mercury in their systems to put a fetus at risk.
Many women eat tuna as part of their daily diet, but albacore tuna can have three times as much mercury in it as light tuna. Women paying more for the expensive albacore, thinking it is better, are actually increasing their mercury levels. The panel recommends only eating light tuna once a week, and wants the albacore tuna put on the 'caution' list along with other high mercury fish such as swordfish, shark, tilefish and king mackerel.
Children are also cautioned not to eat high amounts of tuna, as their smaller bodies have more trouble handling mercury.
Mercury is a heavy metal found naturally in the ocean. It is very slow to leave a body once it is ingested, so fish that are large and live a long time - such as tuna - accumulate a great deal of mercury in their systems over the years. Fish with shorter lifespans do not have time to accumulate as much mercury.
The same happens with humans. A human that eats a lot of mercury over the years often continues to accumulate that mercury in their system.
Note that fish are extremely important to your diet for many reasons, including the omega oils and fatty acids they contain. Please never "swear off" of all fish because you think that is safest or you are afraid of mercury. By that logic you would swear off of ingesting water because some people drown. It is critical to eat enough fish to keep your brain and body healthy. Just make sure that you eat fish low enough in mercury that your body processes it fully.
Mercury Levels in Fish Chart
Omega 3 Fats and Fish Oil
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