Previous to the diet, on the recommendation of our pediatrician we tried fish oil capsules for 4 weeks with good results for concentration. We stopped using the fish oil supplement when we started the diet as we wanted a clear reading of what it would do. (We were very much non believers at this stage). The difference on the diet was amazing and we did the diet very successfully for over three months. We were into our second challenge when I reintroduced the fish oil thinking nothing of it as it was recommended along with diet by the pediatrician. We never got back to where we started even after four weeks of strict diet. We came off it thinking it was possibly a one off and his body had adjusted to the diet. We have paid heavily for it, forgetting what life was like before the diet. My son is unhappy and we even began Ritalin trials feeling that we had exhausted all avenues. Then a friend who is also a failsafer was told by a doctor at the RPA Allergy Clinic that there is a problem with fish oil and I just wanted to warn others who may fall into the same trap. We have begun the diet again today and my son is happy to go back on it even though he knows it means no McDonald parties and fruit and pizza which are his favourites. Thank you for giving us another option, and this fabulous website which makes the daunting task much easier.