The problem with seafood is that although it is “good for you”, it just might, on occasions and in some places, be “bad for you”. The goodness derives from its content of essential, long-chain omega-3 fatty acids, such as docosahexanoic and eicosapentanoic acids, which are essential for brain development. The badness would derive from toxins in fish, such as methylmercury and polychlorinated biphenyls. All fish contain methylmercury, but the only known cases of fetal …