In the current issue of the Journal of Toxicological Sciences, researchers calculated the half-life of mercury inside the body. They had volunteers eat the equivalent of one or two cans of tuna a week for a few months to build up their levels, and then during the subsequent washout period measured how quickly mercury levels in their blood and hair dropped.
They calculated the biological half-life of mercury to be on the order of two months. So it takes only about a year after stopping fish consumption for the body to eliminate 99% of the ingested mercury. Of course that’s assuming one isn’t continually exposed to mercury from other sources, such as amalgam fillings.
How does the mercury intake attributable to those silvery dental fillings compare with the mercury intake due to fish consumption? In my NutritionFacts.org video pick today, I calculate how many mercury-containing amalgam tooth fillings are equivalent to eating a can of tuna once a week (see above).
What about fish consumption compared to the levels of mercury in thimerosal-containing vaccines? See my video Mercury in Vaccinations vs. Tuna.
What’s so bad about eating mercury? In my video Fish Fog I describe the neurobehavioral abnormalities in adults linked to mercury intake, though fetal exposure may be most damaging. The resulting loss of child intelligence linked to maternal fish consumption is estimated to cost billions in lost productivity. See my videos Maternal Mercury Levels and The Effect of Canned Tuna on Future Wages. Dolphin safe does not necessarily mean children safe.
Michael Greger, M.D.
Image credit: TheGiantVermin / Flickr