My mother, from the age of 79 to 87, has not eaten anything except after adding sugar or honey or Sweet juice, it started out hidden from me, then I noticed it, and the sugar was disappearing in less than a week.
Sometimes she puts sugar in a cup of water and drink it may times during the day. 2 years ago i replaced regular sugar with healthy sugar. And she still consumes sugar horribly, and wants to eat sweets all the time.
Sometimes she doesn't notice herself that She puts a lot of sweets in her mouth.
At first, the blood sugar test was terrifying before changing the type of sugar in the kitchen , and now the blood sugar test is moderate..
I try to focus on her condition without eating sugar and with it. Without sugar, she remains sitting or sleeping a lot. With sugar, she seems more energetic.
It seems to give her energy to move.
But her desire to eat sweets scares me a lot.
If I live past 75 I'm not only going to resume my former love affair with cheeseburgers and fries, but also with bourbon whiskey and hot fudge sundaes. I also plan on taking up smoking again at that age. How I LOVED smoking!
So far I concentrate on salts and chips.
I would discuss this with her doctor. Ask for a nutrition consult.
But do understand that we all die, and sounds like she's made it to 87 this way. And is quite satisfied.
I will say, watching Naked and Afraid, it is amazing how long the human body can sustain without much food. Elders eat less and less and sleep more and more.
Good luck to you.