Ah - I see: coconut milk as a source of medium chain triglyceride. Well, MCTs help with epilepsy in some cases (established treatment since the 1920s I think) and there's anecdotal evidence that they help Alzheimer's (don't know if any peer reviewed research has been done - I'm sure it would be easy enough to find out on the interwebthingy). How much coconut milk / coconut oil would be needed, I don't know. It is a source of highly saturated fats, though, so anyone thinking of trying it might want to keep an eye on that. I suppose that if that aspect were taken into account in the diet as a whole, then it wouldn't do any harm and it might do some good. I understand that existing drug treatments for dementia are fairly unpleasant and not wildly effective.