Is That Really Tuna You're Eating?

Is That Really Tuna You're Eating?

You can be seafood savvy and know to order fish that's high in healthy fats and low in mercury. But that doesn't guarantee that what you're served in the restaurant or handed at the fish counter is actually what you requested, a new study suggests.

New York City conservation group Oceana tested 150 samples of fresh seafood collected in the city this year and discovered that 39 percent were mislabeled. In most cases, cheaper types of fish were substituted for more expensive varieties.

The Best and Worst Sushi for Weight Loss

Not only is it disturbing to think that you may be eating some unknown fish when you ordered salmon, there are also many health risks with eating mislabeled fish, says Kimberly Warner, senior scientist at Oceana and leader of the study.

A whopping 94 percent of fish identified as white tuna wasn't tuna at all, but rather escolar, which is also known as snake mackerel. While not poisonous, this fish does contain a toxin that humans don't digest very well, often leading to severe diarrhea.

And at least 13 types of fish, including tilefish and tilapia, were routinely misidentified as red snapper, a concern since tilefish is very high in mercury. Although the minute traces of mercury in most fish causes no problems for most healthy adults, children and pregnant women should reduce their exposure to the chemical as much as possible, as it can cause birth defects and development problems. (Follow these guidelines from the Natural Resources Defense Council to know which types of fish are safest to eat when it comes to mercury.)

The Worst Drinks for Your Body

The results of this study also suggest that if distributors are lying about the types of fish they're selling, they could be lying about other things, such as how fresh their seafood is, Warner adds.

One reason they're getting away with it may be because we import so much—more than 90 percent of our seafood—and the U.S. Department of Agriculture (USDA) can't keep up, she says. "When it comes to seafood, there's very little in the way of oversight and traceability."

The best way to protect yourself against this type of fraud is to develop a relationship with the person or people from whom you buy your fish. By asking questions and shopping as locally as possible, you'll be able to make better, more informed purchases, Warner says. "People who sell seafood know that consumers care about safety. They know you're trying to make good choices."

7 Foods a Nutritionist Would Never Eat

She also suggests writing to your local politicians to ask them to support the Safe Seafood Act, which aims to crack down on fraud and stop seafood mislabeling.

In the meantime, you may want to avoid the white tuna when you hit the sushi bar!

11 Nutrition Myths That Cause Weight Gain

Image Credit: Getty Images