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Secret Side Effects of Eating Canned Tuna, Says Science

Here's what you need to know about mercury.
FACT CHECKED BY Olivia Tarantino

One of the most popular lunch proteins, canned tuna, has some pretty awesome benefits: it's one of the best sources of biologically active, anti-inflammatory, and heart-healthy omega-3 fatty acids; it's a great source of protein; and it's so convenient to eat— making it even easier to have healthy meals in minutes. But despite all the good of this inexpensive protein, there is a catch: One major health complication you have to be cognizant of when eating tuna is mercury poisoning.

You ingest small amounts of mercury—a toxic metal that comes in different forms within the environment—when consuming fish. While there are many types of fish with very low levels of mercury, like anchovies, salmon, and flounder, certain fish, like canned albacore tuna, have high levels of mercury, according to the National Resource Defense Council (NRDC). Generally, exposure to small traces of the chemical from seafood and even some everyday products such as light bulbs and some batteries is harmless, but too much exposure can lead to various, scary symptoms and health outcomes.

Below, we detail four secret side effects of eating canned tuna that may occur by eating excess mercury. Keep in mind, however, that if you stick with the expert-recommended 2-3 servings of fish a week, you can reduce the risk of mercury poisoning and also reap all of the health benefits that eating fish can offer. After, be sure to read One Major Side Effect of Eating Raw Fish, Say Experts.

Mercury can cause delays in children.

canned tuna salad

According to Medical News Today, ingesting too much mercury while pregnant can be dangerous for unborn babies and young children. As a child's brain develops it rapidly absorbs nutrients and mercury can affect that absorption by causing learning disabilities and developmental delays. In infants, high doses of the chemical can lead to cognitive problems such as cerebral palsy and blindness.

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It could affect fertility.

tuna fish

One 2019 study revealed that excess mercury exposure could induce impairments in reproductive function. So, if you're someone who is looking to get pregnant, consider opting for low-mercury fish like salmon or including some plant-based tuna in your diet. Good Catch makes alternatives for fish sticks, crab cakes, and yes even tuna, just to name a few. The tuna is made out of a blend of pea protein, chickpea flour, soy protein concentrate, lentil protein, and navy bean powder. The best part? It tastes just like the real thing.

It could negativey impact blood pressure levels.

can tuna

Research has shown that mercury exposure is linked to high blood pressure (hypertension), higher LDL (harmful) cholesterol levels, and increased risk of a heart attack. Be sure to go easy on the canned tuna, and make sure to vary the fish you eat.

Mercury poisoning can also cause the loss of…

canned tuna

Memory and vision in adults. In addition, tremors, numbness of the extremities could also occur. Other symptoms include trouble walking, lack of coordination, and muscle weakness.

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Cheyenne Buckingham
Cheyenne Buckingham is the former news editor of Eat This, Not That! Read more about Cheyenne
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