I watched my dad fall into depression after retirement. The same for a family friend who was able to retire early in their 40’s. I think a lot of people only plan for the financial side of retirement and don’t plan for post-retirement hobbies and activities. It took these 2 people’s examples to open my eyes a bit and start planning for a heavy hobbying which will also look different from light hobbying where you are still committed to other things like work and raising a family.
I do the xylitol gum! I think countries in asia regularly markets this as part of good dental hygiene for those reasons you listed. Some of the gum containers advertise, white healthy teeth. Not sure why the US doesn’t promote xylitol gum more.