THEY say you are only as old as the woman (or man) you feel and now we’re closer to understanding why.
For some unknown reason, humans live longer if they have more social interactions. Chun-Fang Wu and Hongyu Ruan at the University of Iowa studied fruit flies with a genetic mutation that reduces their lifespan and may be involved in Alzheimer’s and Parkinson’s disease in humans.
They found that mutant flies sharing a home with young flies lived longer, were more active and more resistant to the effects of physical exertion, heat and oxidative stress than those living with…



