We all know that eating fish is good for one’s health. An association has been observed between diets rich in omega 3, a particular type of fat, and the development of intelligence. Still other studies have described an association between quality of sleep and omega 3 in the diet. A recent study has now established that there is a causality relation between all these observations. Eating fish regularly improves the quality of sleep which in turn determines better health and intelligence, which can be quantified in a gain of four IQ points on average with respect to people who never eat fish. Omega 3 supplements would reduce antisocial behavior in young people again thanks to better sleep. We knew that food and health are closely linked but we did not know that the link could be extended to behavior and intelligence passing through sleep.