If your hair is thinning and you can't remember where you left the car keys, last night's fish fillets just might be to blame. According to a new study released by the U.S. Geological Survey (USGS), over a seven-year period, scientists found mercury in every single fish they tested from streams across the country.
This study should put to rest once and for all the old fish story that fish is a "health food."
From 1998 to 2005, USGS scientists tested more than a thousand fish collected from nearly 300 streams nationwide. All the fish were contaminated with mercury, and more than a quarter of them--27 percent--had mercury levels that exceeded the Environmental Protection Agency's safety limits for the average fish-eater. Numerous other studies have also found worrisome levels of mercury and other contaminants in farmed fish and lake and ocean fish, including tuna and swordfish.
Mercury is a documented poison that can cause learning disabilities in children and neurological problems in adults. Elevated mercury levels can lead to brain damage, memory loss, exhaustion, depression, joint pain, hair loss, gastrointestinal disturbances and numbness in the hands and feet. Some studies suggest that mercury exposure can also cause vision loss and increase the risk of a heart attack.
If you don't think Americans suffer from mercury-related health problems, think again. When college student Luke Lindley arrived at StanfordUniversity, he started eating canned tuna as an inexpensive alternative to meals in the campus dining hall. This formerly bright student suddenly found himself struggling to read and study. "I would study four times as long to retain the same information that should have taken me a very short amount of time," Luke told USA Today. "Each day was an ordeal."
Luke also began experiencing insomnia--sleeping only two or three hours at a time--and suffered agonizing gastrointestinal distress. A lab test found mercury concentrations in Luke's hair that were 44 times what the government says is safe.
When Luke stopped eating tuna, his condition improved.
How many other people who think that fish is a healthy source of protein are suffering from the "fish fog" that Luke experienced? According to Dr. Jane Hightower, a San Francisco physician and author of the book Diagnosis: Mercury, perhaps more than we realize. Dr. Hightower identified dozens of patients with high levels of mercury in their bodies, and many showed signs of mercury poisoning, including headaches, fatigue and difficulty concentrating. As in Luke's case, when Dr. Hightower's patients stopped eating fish, their conditions improved.
"Common sense says that if you are not feeling well, and are eating poison, then stop eating it and see if you feel better," says Dr. Hightower. "Most American consumers are simply unaware that the fish they eat could be making them sick."
If you eat fish to boost your heart health, there are safer sources of cardio-friendly omega-3 fatty acids, including walnuts, flaxseed oil, spinach and soybeans as well as vegetarian supplements made from microalgae (which is where fish get omega-3s in the first place). An article published earlier this year in the Canadian Medical Association Journal argues that the purported benefits of fish have been overstated. One study involving men with angina found an increased risk of cardiac death among those who consumed fish oil, and a new Harvard study found that consuming fish and fish oil raises the risk of type 2 diabetes.
None of us would dream of drinking water tainted by sewage, pesticides, heavy metals and other contaminants, yet we'll happily eat fish who are pulled from this toxic brew. Why is anyone surprised when it makes us sick?
The smartest thing we can do for our health is skip the fish sticks and tuna salad sandwiches and reach for nutritious vegetarian options instead.