The Fish Quandary: Getting Essential Oils without the Heavy Metals

A common dilemma for fish lovers today is finding not just tasty fish that children like, but fish that is safe for children and adults. High levels of toxins in some fish make selection tricky. What fish are OK and what varieties are off limits? And can parents and kids alike get docosahexaenoic acid (DHA), an omega-3 fatty acid that's essential to the growth and functioning of the brain, from sources other than fish?

Toxins found in fish—such as polychlorinated biphenyls (PCBs), mercury, and pesticides—affect everyone, especially children and pregnant women. "We see kids everyday with cognitive issues because of heavy-metal toxicity," says Dr. David Perlmutter, a neurologist, author of The Better Brain Book, and medical director of the Perlmutter Health Center, in Naples, Florida.

"Parents should be taking this information seriously about the toxins in fish," warns Dr. Perlmutter. He explains that children who regularly consume heavy metals from a surplus of tuna or other large fish may exhibit slowness of thought, irritability, hyperactivity, sleeplessness, or even experience seizures.

The advantages of getting the DHA and omega-3 building blocks begin in the womb. Research has shown that pregnant women who consume enough DHA are more likely to have full-term babies, says Jeff Bost, a clinical instructor at the University of Pittsburgh's Department of Neurological Surgery. Additionally, a 2005 study from Harvard University found that pregnant women can boost their babies' intelligence by eating fish a couple of times a week—but that the type of fish is important, as babies' intelligence scores drop dramatically if the fish contain high levels of mercury.

Infants who get enough DHA through their mothers' dietary intake (in the womb and through breastmilk) or through formula supplemented with DHA have better cognitive development and vision, adds Gretchen K. Vannice, a registered dietitian and research coordinator for Nordic Naturals, a California-based company that produces toxin-free fish oil supplements.