There seems to have been a few studies as described here: https://www.discovermagazine.com/health/the-growing-science-behind-a-fasting-treatment-for-alzheimers

There seems to have been a few studies as described here: https://www.discovermagazine.com/health/the-growing-science-behind-a-fasting-treatment-for-alzheimers https://www.discovermagazine.com/health/the-growing-science-... But, in my opinion there is more research to be done here to establish whether or not (and to what degree) there is a strong link