Pregnant women and children should stick to smaller servings of tuna to avoid mercury. Otherwise, tuna is a healthy (though overfished) source of protein.
Chief among worries about tuna is mercury. Mercury that's attached to a circle of atoms called a methyl group becomes methylmercury. It sticks around in your body. Accumulate to much or pass it to a fetus during pregnancy and it can do damage to the nervous system.
Methylmercury accumulates in the flesh of ocean predators like tuna. Albacore tuna has quite a bit - the FDA recommends no more than a six-ounce serving a week for pregnant women or children. Canned tuna does not generally include albacore and has less. Children and pregnant women are safe to eat twice as much - 12 ounces a week.
There are health benefits to eating tuna as well. It's rich in unsaturated fatty acids, which are better for you than saturated fat. It's also got the vaunted omega-3 fatty acids. They work together with omega-6 fatty acids in somewhat mysterious ways; the right combination, or the right absolute amounts of both, seems to improve heart health and lower risk of disease. The science on the right way to consume omega-3 is still developing. Consuming moderate amounts, however, appears to be good for the heart.
Tuna also has vitamins that we need. One serving contains most of the niacin (vitamin B) that we need in a day. It's used all through the body and is regarded as an essential nutrient. Tuna is also rich in vitamin B12, which the body needs for your blood, your brain, and your DNA.
One serious problem with tuna is our hunger for it. Overfishing has wreaked havoc on tuna populations around the world. A 2013 article in the Guardian reported that the bluefin tuna population in the Pacific had dropped a terrifying 94%. One bluefin sold in Japan for well over a million dollars.
If the trend continues, bluefin will go extinct in the Pacific - the ocean that supplies two-thirds of the world's tuna. Bluefin is one species, and they make up a fraction of the overall tuna population. Eating tuna, however, contributes to pressure on that overall population and will shrink it further until further checks are introduced.
Possible long-term side effects
- methylated mercury can do damage to the nervous system
Ingredients to be aware of
- great source of protein
- great source of healthy fats
- promotes heart health
- promotes weight loss
- decreases risk of various diseases