So sorry to hear about your grandmother. Prayers go out to you dear.
Sometimes I feel giving advice or "remedies" in this scenario will not make it any easier, since all of us are heading towards a similar fate, but I suppose I'll do what I do best...
Three things that helped my own family member (who passed last year):
Number one, activity. The ageโold saying "use it or lose it" rings true even for our minds. Studies have shown that retiring is connected to quicker expiration due to inactivity on the physical and mental front, and I have seen firsthand what sedentary lifestyles do to people.
The second thing that's equally important is hydration and high fat/protein rich foods (if she consumes little, hydrating foods like softโcooked eggs, lamb, salmon and soups with a little butter or tallow are excellent for the brain).
Last but not least, time with loved ones and prayer (also proven to delay the effects of dementia).
Alas, there is nothing you will regret more than where you spend your time. Hold fast to that which is good. God bless youโฅ