Aquaculture has the potential to take the pressure off wild fish stocks whilst meeting the dietary needs of the population for omega 3 fatty acids and other key nutrients such as vitamin D. The industry is working hard to improve sustainability - between 1995 and 2006 it has been estimated that the input to output ratios for salmon improved from 7.5 to 4.9 and trout from 6.0 to 3.4- but there is a need to do more. Reductions in fish stocks and catch quotas, in addition to sustainability considerations, mean that farmed fish may have to be raised on vegetable oils for example but this may reduce the omega 3 content and may affect the content of other nutrients. Fish are an important component of the diet and there is a need to understand the effect of pressures from sustainability on methods of production and the health giving properties of fish. We have now been commissioned by the Scottish Government's Rural and Environment Science and Analytical Services Division (RESAS) to do research on the health effects of Scottish farmed fish fed different feeding regimes in the Scottish population, and assess how differential effects in measured health outcomes could be related to fish composition.