Sometimes I can be very hungry in the middle of the night or the night before but then wake up not hungry.
I think to change your shape from an extreme apple shape will take a very very very long amount of time and be almost imperceptible as it's happening. The best thing she can do is just eat healthy, exercise, avoid too much alcohol (seems that a lot of heavy drinkers have apple-shapes, not that I'm saying your mom is because I don't know her) get enough sleep and hope for the best.
Also, any time in my life that I've ever lost weight, no matter how light I got, I was always the same shape. I can hardly tell the difference. I still have the belly rolls, the big thighs, the lack of a waist.
Female, 5'3", 48, Starting weight: 163lbs. Current weight: 135.
Starting bench press: 30lbs. Current bench press: 77.5lbs.