Mercury is a toxic heavy metal to which we’re primarily exposed through fish. Eating tuna, for example, may cause enough brain damage to significantly lower intelligence. It is both a neurotoxin that affects brain function in adults, in teens and in infants, as well as a cardiac toxin that may contribute to atrial fibrillation and fatal heart attack risk. This may counteract the anti-inflammatory benefits of omega-3 fatty acids. Women who eat a lot of fish should consider getting tested for mercury (via hair testing) before getting pregnant. Fish oil supplements and Ayurvedic medicines may also be contaminated with mercury (see also here, here).

Other sources of mercury include factory-farmed chicken and dairy and foods containing high-fructose corn syrup (see here, here). Mercury exposure in amalgam tooth fillings and childhood vaccinations pale in comparison to the amount of mercury exposure that comes from eating fish. Eating a plant-based diet, including plant-based omega 3 supplements instead of fish, would be expected to significantly reduce exposure to toxic heavy metals.

See also the related blog post: Mercury Testing Recommended Before Pregnancy.

Topic summary contributed by Elizabeth Stolle.
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