 Earlier this year, consumer reports published some new tests on tuna, confirming that just a single serving, like half a can of white tuna, would put women of child-bearing age over the EPA mercury safety limit. Light tuna tends to have less than white tuna, but they've found sometimes it can have twice as much. Bottom line, they recommend children and premenopausal women eat no more than a can of wheat, and pregnant women should avoid canned tuna entirely. Last year, scientists at the Harvard School of Public Health attempted to calculate what effect a reduction of mercury intake might have for our population, given that methylmercury is a known human developmental neurotoxicant, as well as may increase fatal heart attack risks. They calculated that if we could just drop our mercury exposure down 10%, we could save our country $860 million a year, most of which would be associated with reductions in fatal heart attacks and the rest with IQ gains. The CDC estimates that every extra IQ point we have translates into about 1% future higher earnings in life, in terms of hourly wages. So lowering our mercury intake is healthy for our brain and bank account. On a practical level, what does reducing our exposure mean? Well, we can try not to live next to a volcano or coal-fired power plant, but fish consumption is the major source of methylmercury intake.