[1] is a study of the Tsimane people by anthropologists which somewhat, to my mind, casts a shadow on the APOE4 Alz hypothesis. Doesn't rule it out, but suggests the Alz space is much larger than amyloid protein bundles, as the nymag piece suggests. [2] is the record of the Tsimane project
I suspect so. There is more and more anecdotal evidence that Alzheimer's and other similar diseases are cause by insulin resistance in the brain. However there is unfortunately no gold standard double blind research out there to confirm/deny it yet.
[1] https://www.nytimes.com/2017/07/14/opinion/sunday/alzheimers... [2] https://tsimane.anth.ucsb.edu/