I have often read quite alarming things about the amount of mercury in your average can of tuna. Does anyone else avoid tuna for their kids? [[http://www.amazon.co.uk/gp/product/1582437025/ref=s9_simh_gw_p14_d0_i1?pf_rd_m=A3P5ROKL5A1OLE&pf_rd_s=center-1&pf_rd_r=1S76JJ0B3YVVT0BPGC6N&pf_rd_t=101&pf_rd_p=219600407&pf_rd_i=468294 this book, among others]]