You should start eating fish when you want more mercury. Not everybody is sensitive to mercury. Not everybody needs to have their Amalgams out. If you have symptoms of MP, depression,chronic fatigue, autistic like symptoms,brain fog or other chronic health issues than you have to consider mercury as a possible source of the problem. IT takes about ten months to get most of mercury out of your body. IF you eat fish today some of the mercury will still be in your body ten months later.