What is "xenohormesis"

Xenohormesis explains how certain molecules such as plant polyphenols, which indicate stress in the plants, can have a longevity-conferring effect in consumers of plant (i.e. mammals). It was first used in the paper "Small molecules that regulate lifespan: evidence for xenohormesis." by Dr. David Sinclair and colleagues from Harvard Medical School. Further studies then picked up the term.

If the plants an animal is eating are under stress, their increased polyphenol content may signal forthcoming famine conditions. It could be advantageous for the animal to begin to react—i.e. to hunker down to prepare for the lean times to come. The effects researchers have observed from resveratrol may be just such a response.