Hi P.,
Most weight problems usually have to do with toxins in the system. A gentle fiber/colon cleanse (I know one if your interested) will remove the toxins from her colon so the nutrition she is eating will actually absorb into her bloodstream as it is supposed to. A probiotic/prebiotic will help as well.
Try looking into low glycemic index foods. These are foods where the carbs/sugar metabolizes slowly. You can google it for more information. She can eat as many of those anytime of day and it won't make her gain weight and it should help her lose some too.
Meds can change the body chemistry so it could have something to do with her new medication as well. Even if it does, the above information is still good.
God bless!
M.
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