A human study for evaluating aging interventions could compare intensive lifestyle intervention in high-risk individuals to a control group.

“you find someone who is overweight diabetic and smokes and has hypertension you get hundreds of these folks you put half of them on a sort of to be ethical a plan where you try to get them to stop and presumably many don't right but on the in the other group you pull out all the stops and you don't care because you're interested not in testing the hypothesis does this thing help you you're interested in getting them to lose weight not have diabetes stop smoking exercise like crazy”