The TRUTH About Mercury Poisoning: A Survivor's Girlfriend Reveals All

An article was published earlier this week in Environmental Health Perspectives (EHP) (a peer-reviewed journal sponsored by the National Institutes of Health & various other government agencies) stating “that limiting seafood intake during pregnancy may have a limited impact on prenatal blood mercury levels”. Several media outlets took this information and ran with it, publishing articles titled, “Concerns over mercury levels in fish maybe unfounded” and “Consumption of fish may have little effect on mercury levels in pregnant women”.

These news groups are missing a crucial detail in their reports citing EHP's research: the data referenced in the study was collected twenty years. EHP analyzed data gathered by the Avon Longitudinal Study of Parents and Children (ALSPAC), a study that evaluated blood samples and diets of pregnant women in the United Kingdom between 1991-1992, to see how certain lifestyle factors affected offspring. Twenty years ago, mercury levels found in fish, were far lower than what is found in our environment today. Present day, agricultural run-off and other pollutants have tainted our waterways and affected our food chain. There is much evidence to suggest that mercury levels are high in fish and even non-pregnant people should avoid eating too much fish. Though eating fish does provide nutrients that other types of food don’t provide, eating too much of the wrong type of fish could also turn you into a zombie (or make you act like one).

Fig.1 Sushi-a dinner delight or a secret killer?

I make these statements refuting the claim that concerns over mercury levels in fish are “unfounded” because I have personal experience with this topic. Earlier this year, my boyfriend, someone I eat with frequently, got mercury poisoning. He stopped eating meat, to be “healthier”, and supplemented his diet with fish (purchased at places like Whole Foods or the local fish market). All of a sudden he started feeling unwell, with symptoms like massive headaches, tinnitus (ringing in the ears), and (zombie-like) mood swings. After several rounds of doctor visits and every sort of test possible, a simple blood test revealed high levels of mercury. A "normal" mercury level is less than 10 and his were in the mid-20s. If mercury poisoning had such a major affect on the health of a hyper-fit yoga instructor, I can’t imagine how it could affect pregnant women.

So the burning questions... How much fish can I eat before I start acting like a zombie? And do certain fish have higher levels of mercury than others? The quantity and frequency of fish that is safe to consume depends upon species, location, and fish size. Ahi tuna, one of the main species of fish found on restaurant menus and grocer’s ice beds, has one of the highest levels of mercury. (http://www.nrdc.org/health/effects/mercury/sources.asp)

Fig.2 List of fish with high levels of mercury from the Monterey Bay Aquarium

A number of seafood watch agencies, aquariums, and natural resource agencies measure mercury levels in fish and publish reports detailing which fish are ok to eat and in what quantities. Two good resources are:

1. Monterey Bay Aquarium’s website—you can even print out pocket guides or get an app for your phone. (http://www.montereybayaquarium.org/cr/cr_seafoodwatch/sfw_recommendations.aspx)
2. Office of environmental health hazard assessment—you can search levels of mercury in fish by location, so if you fish or like to buy locally-sourced fish, this is a great resource. (http://www.oehha.ca.gov/fish.html)

Mercury poisoning is a very real health threat. Be diligent when choosing fish to cook or eat. And if you tend to eat a lot of sushi or if fish is your main source of protein, get your mercury levels tested.