A recent study by van Wijngaarden et al. examined the claim that pre-natal mercury exposure, through the likes of eating oily fish in high amounts, may be associated with autism spectrum disorder (ASD). A cohort of 1784 people from the Republic of Seychelles (where fish consumption is high) were recruited, and interestingly no consistent association between prenatal methylmercury exposure and ASD screening was found.
This is interesting to the field of dietetics as we commonly advise pregnant women or women likely to become pregnant in the future to eat only up to two portions of oily fish a week due to the risk of exposure to pollutants such as mercury. However this isn’t to say that the recommendations are incorrect, as pollutants such as dioxins and dioxin-like PCBs (by-products of industrial processes which can cause reproductive and developmental problems) still exist in oily fish due to their lipophilic properties. It is however interesting that methylmercury does not seem to cause ASD; the study focused on mothers with mercury levels 6-10 times higher than that of the USA or Europe, and therefore highlights there is probably no risk to the Westernised society if there was no risk to the mothers in the study. The study adds somewhat to the growing evidence that the benefits may outweigh the risks when it comes to fish consumption during pregnancy, particularly with oily fish containing much-needed omega oils.
- Study Sees No Link Between Mercury Exposure, Autistic Behavior (webmd.com)
- No link discovered between mercury exposure and autism-like behaviors (medicalnewstoday.com)
- Mercury And Autism Not Linked, Again (forbes.com)