In his masterful book “Lifespan: Why We Age- And Why We Don’t Have To” David Sinclair asks, “What if, in our 60’s, we weren’t fretting about leaving a legacy but beginning one? What if we didn’t have to worry that the clock was ticking? In fact, he makes the case that we are closer than you think to changing what “old age” looks like, feels like, performs like. David Sinclair is an optimist of course, but he’s also a Harvard professor and one of the most prolific researchers in the area of aging, or senescence. His lab has turned out paper after paper, building and transforming our understanding of the aging processes. Some of the things he has uncovered have rapidly entered the mainstream, at least the mainstream consciousness of groups willing to act on early information, before it is proven and tested in prospective trials. We have learned that a little bit of stress is good for the body, for example, periods of cold, periods of fasting, eating less volumes of food (even 12% less) than most, exercising daily. He does not preach extremes- a brisk cold walk after dinner will do.