Deletion of Il11 extended the lives of mice by 25%
nature.com
nature.com
Actually the point of healthspan vs lifespan is made in the introduction -- it was a justification for using mice for this study, which have clear health phenotypes that are analogous to humans.
Metabolic adaptations that prolong the life of mice might be just bringing them closer to where we are as opposed to something that would work for us.
Discussion: https://news.ycombinator.com/item?id=40987224