The polyunsaturated fats found in fish oils may promote longevity by triggering autophagy, a process that helps cells to survive starvation conditions by degrading and recycling excess cell components.

A team led by Gary Ruvkun of Massachusetts General Hospital in Boston found that when they starved the nematode worm Caenorhabditis elegans, the creatures boosted their production of omega-6 polyunsaturated fatty acids — which are found in fish oils. Supplementing cells from C. elegans and humans with these fatty acids activated autophagy. Worms fed omega-6 fatty acids lived longer than those that did not receive the fats — an effect erased by disabling the worms' autophagy machinery.

This mechanism could explain the health benefits that are seen in people who eat diets rich in fish oils, the researchers say.

Genes Dev. http://dx.doi.org/10.1101/gad.205294.112 (2013)