Professor Michael Crawford, director of the Institute of Brain Chemistry and Human Nutrition, at London Metropolitan University, suggested that dependence on a meat and wheat-based diet is resulting in a significant rise in brain ill-health in the Western world.

"Currently, just over 50% of the Irish population eats fish at least once a week," said Prof Crawford, a Bord Iascaigh Mhara-sponsored keynote speaker at the Irish Nutrition and Dietetic Institute conference.

His key message to the Irish is to eat more fish and substantially lessen their risk of developing mental health problems.