[YokoZar]

While it's true that preventing cancer means you're likely to die in a few years of heart disease, and preventing heart disease means you're likely to die in a few years of cancer, solving both will add dramatically more than both effects combined to both life and healthspan.

Those really are the big two - as the graphs in the article show, the next biggest things are much smaller and much less likely to get you, which means you live a lot longer and healthier.