It has been conjectured that the diet in the Human [Environment of Evolutionary Adaptedness]? may have been rich in seafood, and that modern diets are deficient in their balance of Omega-3 to [Omega-6 fatty acids]?, perhaps leading to a number of modern illnesses.
There are preliminary reports that supplementing the diet with large doses of omega-3 oils may act as a mood stabilizer. However, care must be taken to avoid overdose, and more research is needed.
Lower doses may also have beneficial cardiovascular effects. Again, more research is needed.
References: