ReviewLinoleic acid and the pathogenesis of obesity

•Worldwide linoleic acid (LA) intakes have increased due to nutrition transitions.•LA intake exceeds what is required and may have detrimental health effects.•Excessive LA intake has been implicated in the development of obesity.•Excessive LA may contribute to the chronic inflammatory state found in obesity.•Genetics and maternal diet influence the effect of LA on obesity and inflammation.

The modern Western diet has been consumed in developed English speaking countries for the last 50 years, and is now gradually being adopted in Eastern and developing countries. These nutrition transitions are typified by an increased intake of high linoleic acid (LA) plant oils, due to their abundance and low price, resulting in an increase in the PUFA n-6:n-3 ratio. This increase in LA above what is estimated to be required is hypothesised to be implicated in the increased rates of obesity and other associated non-communicable diseases which occur following a transition to a modern Westernised diet. LA can be converted to the metabolically active arachidonic acid, which has roles in inducing inflammation and adipogenesis, and endocannabinoid system regulation. This review aims to address the possible implications of excessive LA and its metabolites in the pathogenesis of obesity.