"A Medical Mystery of the Best Kind: Major Diseases Are in Decline"

"it looks as if people in the United States and some other wealthy countries are, unexpectedly, starting to beat back the diseases of aging. The leading killers are still the leading killers — cancer, heart disease, stroke — but they are occurring later in life, and people in general are living longer in good health... 

Dementia rates, too, have been plunging. It took a few reports and more than a decade before many people believed it, but data from the United States and Europe are becoming hard to wave off. The latest report finds a 20 percent decline in dementia incidence per decade, starting in 1977."

http://mobile.nytimes.com/2016/07/10/upshot/a-medical-mystery-of-the-best-kind-major-diseases-are-in-decline.html?rref=collection/sectioncollection/health&action=click&contentCollection=health&region=rank&module=package&version=highlights&contentPlacement=1&pgtype=sectionfront&utm_source=Sailthru&utm_medium=email&utm_campaign=Vox%20Sentences%207/8/16&utm_term=Vox%20Newsletter%20All&referer=

I think it's something about slower aging. Aging research has been a big deal for a while now and it turns out to be a super flexible phenomenon. 

I suspect that the past 100 Years if environmental, food, and workplace reforms have had a positive impact.