One of the most frequent questions women have when advised to use fish oil is whether or not they should be concerned about the mercury content. I routinely hear from clients I've worked with that they feel comfortable taking fish oil to conceive, but then once they're pregnant they become concerned about mercury and stop the supplements.
The FDA has done such a great job of warning us about the potential problems with just four kinds of fish--shark, swordfish, king mackerel, and tilefish--that Americans in general have decreased consumption of ALL fish.
With regard to fish oil supplements, the truth is, most brands of fish oil are molecularly distilled, meaning they go through a very strict purification process to remove mercury. Random tests from bottles pulled off of regular drugstore shelves have consistently shown that for the most part…fish oil supplements are safe.
Yet people continue to question the safety of fish and fish oil because they fear the mercury.
Here's an interesting twist in that logic.
Earlier this year, two studies looked at the mercury content of high-fructose corn syrup (HFCS), a ubiquitous and controversial sweetening agent. One study discovered that nine of twenty samples of HFCS contained measurable amounts of mercury. These researchers concluded, "With respect to total mercury exposure, it may be necessary to account for this source of mercury in the diet of children and sensitive populations." I would consider women of childbearing age, including those reading this blog, to be an especially sensitive population.
A second study conducted by the Institute for Agricultural and Trade Policy found in foods they analyzed in the fall of 2008, nearly 1 of 3 of the 55 foods they sampled contained measurable amounts of mercury. The finding was most common in foods containing HFCS.
So if you're using mercury concerns as an excuse to avoid eating fish…and you're looking for ways to justify keeping sweet stuff in your diet…you may want to consider your perspective. It's the fish that's likely clean and the sweets that may be dirty.
Dufault R, LeBlanc B, Schnoll R, Cornett C, Schweitzer L, Wallinga D, Hightower J, Patrick L, Lukiw WJ. Mercury from chlor-alkali plants: measured concentrations in food product sugar. Environ Health. 2009 Jan 26;8:2.
http://www.iatp.org/iatp/press.cfm?refID=105025