The protagonist in One Second After has a daughter with stage 1 diabetes.
The story details the importance of having the appropriate supply of medications (and methods of keeping those medications at the right temperature, without electricity) to address any pre-existing medical conditions, like diabetes, asthma, cancer, high blood pressure, etc.
Sometimes you just gotta eat what you gotta eat.
Today my wife was asking for spam.
I said we have treet and western luncheon meat. (x date was near)
I want spam, not treet, I told you not to buy treet.
My reply, well in shtf, if there is no steaks, you ain't eating, cause there won't be any steaks then.
In shtf you can't control your diet, especially if your not a millionaire.
You won't even be able to control your meds. You will be lucky to have a functioning health facility.
The current problem is that they don't and won't let you accumulate meds. Sometimes only a months worth is allocated.
Back to food, stock up on whatever you can afford even if it is $1.00 can of refried beans or .50 pork and beans.
You can also think of these foods as currency. Cheap food now, but a can of value to trade or barter.
Dumpster Diving ain't fun and in shtf, it will be outright dangerous, competitors will be all around, and zombie looking.