fish is a very fine diet for diabetics , and only if you eat very much fatty fish of the bigger kinds you will get a lot of toxins/pollutioning stuff into your body... because the higher the fish is in the food chain the worse it is polluted from all the other fish it eats besides the general polution in the seas...
herring is quite a small fish not so high in the food chain but still very fatty and maximum healthy if you want to eat fatty fish more than once a week..
the pollution is most dangerous in girls who haven´t gotten their children yet (as the pollution of the worst kind stays in the body and raises when eating more and more) and in childbearing women and breatsfeeding women... as the polution can damage the featus somewhat and even do some brain damage in the unborn or newborn child who´s brains and nervesystem are not finnished in Building yet..
older people don´t have to think as much of it if they don´t care much of pollution.. and living shorter or havin´t a bit lower intelligence than they´ve could possibly have had