TL;DR
Some dogs stay bright-eyed and quick on their feet deep into old age, and others slow down early. Nobody can yet say why. The U.S. National Institutes of Health is putting $29 million into finding out, according to one trade report: five more years of the Dog Aging Project, which already follows nearly 55,000 pet dogs living ordinary lives in ordinary homes. The new phase moves from describing how dogs age to explaining it, by testing the water they drink, tracking the pollution around them and reading the genes of the ones who live longest. Because pet dogs share our houses, our air and often our habits, and age several times faster than we do, what helps them age well could point to what helps people age well, years before a human study could answer. The same project is running a trial of rapamycin, one of the most-watched drugs aimed at slowing aging itself, with results still to come. For the odds that dog research leads to aging treatments for people, and a timeline of the steps along the way, subscribe.
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