Could it be that parkinson's starts off with there not being enough stomach acid
( Hydrochloric acid ) that the stomach ( digestive system ) is unable to break down your food into amino acids, fatty acids and so forth which is the reason that the gut is unable to feed the brain what it needs to function correctly?
john Gray puts his case'
And i went looking for that study and i think this is it..
dovepress.com/amino-acid-ma...
I Believe that Digestive Enzymes, Coconut oil would be of great benefit to the above protocol.
Digestive Enzymes to help with the breakdown of food and coconut oil which converts into ketones
which is another energy source for the brain to help it function better.
Also here is his blog