I guess the most important thing to remember is the different terms being used now which basically mean the same thing. But you probably already know them.
Low Carb
Keto
Paleo
These are loosely very similar.
What seems to be coming together is that Ketogenesis itself depresses the symptoms of many diseases/disorders by reducing inflammation.

Dr. Terry Wahls gave herself the ability to walk again even though she suffers from MS. Dr. Dale Bredesen has a protocol which is helping people with Alzheimer's Disease reclaim their lives. Dr. Permutter is do much the same for Parkinson's Disease. All the neurological disorders which attack the elderly can be mitigated by ketogenesis.

Specific to RA:
https://bengreenfieldfitness.com/po...-seamus-mullen/

AD:https://www.apoe4.info/wiki/Bredesen_Protocol

I hope this points you toward some information you can use.