My mother is hiding and hoarding food (the "forbidden" kind loaded with salt, sugar and fat and starches) in her room. She lies that she is doing this but there are moths in her room and one time I found her night table drawer full of them.
She knows that being diabetic she is not allowed to eat these cookies, candies and chocolate and whatever else she can hoard. She has even tried to coerce outside carepersons who come in once a week to buy and bring her things!!
The only way I can see around this is to search her room while she is out but she is so clever, she keeps things in her purse and coat pockets, she will eat these things when she goes for "her walk".....
Her dr. has repeatedly told her what kind of diet to maintain but she lies to him about what she eats, lies when hospitalized that she does NOT have diabetes and tells everyone "I am borderline but I maintain it with food" yeah, RIGHT!! the kind you're not supposed to have!
She even reported me once for elder abuse because I tried to make sure she was eating properly! If she goes out she makes sure it's somewhere where she can gorge on all the wrong things.
It's out of control!!
I'm not sure there's a way you can prevent this but you can make it a habit to go through her room and clear away any food items you find. You said she keeps food in her coat pockets? Check her coat pockets. As you know, food laying around will attract all kinds of critters not to mention the fact that your mom shouldn't be eating that kind of food with her diabetes. But if she's intent on getting her hands on that food cut her off at the source. Tell people they are not to bring her any treats, that you are having a difficult time controlling her diabetes and she can't eat foods like that.
Other than going through her room (and coats) and cutting off the sources I don't know what else you can do.
She is so very stubborn and determined to get what she wants.
On top of that, I have to field the comments from friends and family who are part of two different camps: one says "she's old, she's sick, let her eat what she wants, she's nearly 90" and the other says "you're going to have to be more strict with her". Oh yeah?
I have already told my children and her carepeople who come in once a week to bath her NOT to bring in anything - but she still tries. On top of this we (our family) follows religious food commandments which she has no respect for and when she goes out she makes sure she gets to eat those foods which we do not.
She is very, very clever at lying and hiding these things and even takes the wrappings off them out to the garbage outside our building so I won't see them!!