Aged 97

It is a truth little understood that a mind riddled with dementia so bad that it cannot remember ten seconds ago, has the determination to hold on to a single particular thought through days of increasing physical pain. 

The thought is this; "If I refuse water and food,  I will be released from this intolerable existence; I will die, and that is now my greatest wish."

It can take a week. The strength of mind is astonishing.