Hi friend. My heart goes out to your mother. Illness comes from toxins that are building up in the body. That's why older people are more prone to chronic ailments. Physicians call it "old age", or "genetic" because they don't have an answer. Toxins cause genetic changes, too.
Make sure the she is free of infections, including candida, which can be a great toxifier, and make sure that she her intestinal flora is well established. This not an easy task. If antibiotics have ever been administered, out beneficial bacteria may be too low to protect and cleanse. No one stays healthy when their intestinal flora is compromised. It leads to unhealthy build-up in the GI tract, creating more toxins in the blood. The colon will ultimately back-up into the liver, causing dybiosis/dysfunction. Toxic build-up will lead to glandular irregularities and disruption of bodily systems...ie, chronic disease.
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Home-made kefir, allowed to culture for 24 hrs. has many beneficial bacterium and yeasts. It leaves yogurt in it's dust. Using non-pasteurized milk to culture it, is a real plus. Home-made Kombucha tea ferment is a raw sulfury cleanser for liver and kidney. Some have cleared cancers with it. People have also been healed dramatically using Himalayan Goji Juice (www.gojihealthstories.com). Taking a drop or two of 35% hydrogen peroxide in a glass of water 45 minutes before breakfast is cleansing. Raw food is very good...organic raw is one step better. Make sure she is not living with cigarette smoke, also household chemicals can be very toxifying. Is she sensitive to anything...perfumes...cleaners...chlorine...fabric softener...petro distillates? If she is, they may weaken her adrenals/stress related. Cleanse...cleanse...cleanse!
God bless you...