Food hysterics seem to enjoy pulling their hair out over the supposed effects of mercury in fish. What they'll never mention is a little element called selenium. Selenium is a nutrient essential in small amounts for the human body. Fish is a good source of selenium, although, as dietitian Mary A. Keith explains, you aren't likely to hear seafood scaremongers mention it any time soon:

Even children may have up to 12 ounces of light tuna per week; adults can have 12 ounces for each 100 pounds of body weight, and still be within safe limits. Plus, tuna and other seafood have plenty of selenium to protect us from the mercury. So we're better off eating it than not.

How does selenium protect us from mercury? Last year, scientists at the University of North Dakota did some research on mercury levels in fish. They found that the concerns over mercury levels were exaggerated, thanks in part to selenium:

"Selenium is an essential nutrient in healthy brain development and protects the brain from oxidative damage," said Dr. Nick Ralston, an EERC Research Scientist involved with the studies. "More importantly, selenium protects the body from mercury's negative effects. The more selenium in the tissue, the less mercury toxicity occurs. Since fish in some areas have much higher levels of selenium than mercury, the consumer receives the healthy benefits of selenium and a natural defense against mercury," he said.

The Center for Consumer Freedom published a study of 142 fish samples collected in Madison, WI, and found selenium levels as high as 3.215 parts per million (in cooked walleye). Our report, titled "The Flip Side of Mercury," showed that the highest concentration of mercury in any of the fish was less than 35 percent of what the FDA classifies as remotely harmful. And the selenium helped offset the mercury concentrations.

Fish has more goodness than just selenium, of course. An eight-ounce can of light tuna contains 123 percent of your recommended omega-3s for the day, 116 percent of your protein needs, and 113 percent of the Vitamin B12 you need. It also contains 331 percent of your selenium for the day, judging from the USDA 's Reference Daily Intake numbers. For more information about the health benefits of eating seafood, point your internet browser to HowMuchFish.com and try the Internet’s only balanced seafood calculator.

And the next time smug seafood scolds corner you about your tuna sandwich, ask them if they've ever heard of selenium. Because if there's one thing the health-food police hates more than mercury, it's learning that they’re not so smart. A little more seafood in their diets might help. It’s brain food, in case you hadn’t heard.