Klerman and Weissman (1) considered increased rates in Western societies and concluded that such changes could not be explained by changing diagnostic criteria, changing attitudes of health professionals and societies, reporting biases, differential mortality rates, or other obvious artifactual influences. In the last 150 years, rapid expansion in Western populations has been associated with a change in diet, witli omega-3 polyunsaturated fatty acids from fish, wild Same, and plants being replaced by saturated fats from domestic animals and omega-6 polyunsaturated fatty acids from common vegetable oils (corn, safflower, and soybean) and other sources. For example, epidemiological evidence from the U.S. Multiple Risk Factor Intervention Trial for 12,866 middle-aged men identified significant inverse relations between omega-3 levels and cardiovascular disease (7). In relation to depression, both Smith (8) and Hibbeln and Salem (9) suggested that the sharp rises in rates of depression and other neurological disorders in the 20th century are being fueled by increased consumption of vegetable oils rich in omega-6 tatty acids.