PURPOSE OF REVIEW: This review discusses recent advances in delineating basic mechanisms underlying the beneficial effects of omega-3 fatty acids on health and on disease.

RECENT FINDINGS: While a substantial number of studies have delineated many differences between the biological effects of saturated versus polyunsaturated fatty acids, less is known about the long-chain omega-3 fatty acids commonly present in certain fish oils. In this review, we focus on recent studies relating to basic mechanisms whereby omega-3 fatty acids modulate cellular pathways to exert beneficial effects on promoting health and decreasing risks of certain diseases. We will use, as examples, conditions of the cardiovascular, neurological, and immunological systems as well as diabetes and cancer, and then discuss basic regulatory pathways.

SUMMARY: Omega-3 fatty acids are major regulators of multiple molecular pathways, altering many areas of cellular and organ function, metabolism and gene expression. Generally, these regulatory events lead to "positive" endpoints relating to health and disease.