Open any health or women’s magazine, and you’ll eventually come across a recommendation to “eat more fish.” Fish perplexingly continues to be touted as a “health food,” despite the fact that many of the species that people commonly consume-most notably tuna-are contaminated with mercury and other toxins. So why is it considered “healthy”? Because-compared to other meats, which are loaded with saturated fat and cholesterol and are often contaminated with hormones, antibiotic residues, and/or dangerous bacteria-fish is considered by some to be the lesser of meaty evils. But when you compare fish to truly healthy vegetarian sources of protein, it isn’t a health food at all.

When The New York Times bought and tested tuna sushi from 20 Manhattan stores and restaurants, several of the samples were so tainted with mercury that federal regulators could confiscate them for violating food safety rules. Experts believe that similar results would likely be found in other parts of the country as well.

As the Times study suggests, tuna-and other fish-are often contaminated with mercury, which can lead to an increased risk of neurological symptoms such as memory loss, tremors, joint pain, and gastrointestinal disturbances, and have recently been linked to cardiovascular disease.

San Francisco physician Jane Hightower, author of the book Diagnosis: Mercury, found that dozens of her patients had high levels of mercury in their bodies, and many showed symptoms of mercury poisoning, including hair loss, fatigue, depression, difficulty concentrating, and headaches. When her patients stopped eating fish, their symptoms disappeared.

The Wall Street Journal reported on one of Dr. Hightower’s patients, 10-year-old Matthew Davis. Matthew had always excelled in school, but suddenly, he was missing assignments and struggling with basic math. His teachers said that Matthew could barely write a simple sentence. What’s more, Matthew’s fingers had started to curl, and this formerly excellent athlete could no longer catch a football. One specialist told Matthew’s parents that their son had a learning disability.

The real culprit was the canned tuna that Matthew had been eating for lunch and snacks. Tests revealed that Matthew’s blood-mercury level was nearly twice what the Environmental Protection Agency says is safe. After Matthew quit eating tuna, his blood-mercury level returned to zero, and his condition dramatically improved.

This is far from an isolated case. Secretary of State John Kerry reportedly stopped eating most fish after tests revealed that his mercury level was “sky-high.” A 2006 study found that one in every five women of childbearing age has mercury levels that exceed the government’s acceptable limit. Women who eat fish at least twice a week have the highest levels.

Mercury is just one of several toxins found in fish, including DDT, PCBs, and dioxin, which have been linked to cancer and nervous system disorders. The good news is that you don’t have to risk poisoning yourself in order to obtain the heart-healthy omega-3 fatty acids that are found in fish. Walnuts, flaxseeds and flaxseed oil, pecans, broccoli, spinach, and soybeans all contain omega-3 fatty acids. Vegetarian supplements made from microalgae contain DHA, one of the omega-3 fatty acids found in fish.

So instead of tuna salad for lunch, why not try a Tasty “Toona” Salad and spare yourself the health risks.