Interestingly, body acidity is implicated in many diseases and many diseases can be signs of long-term acidity. Osteoporosis, digestive problems, poor immunity, arthritis, kidney diseases and gout, and cancer can all be triggered by long-term acidity according to one website, awaytofitness.com. While no one knows what causes cancer, the macrobiotic diet that some have found helpful is based on the Acid & Alkaline theory written about by Herman Aihara. I found at chimachine4u.com that "At a pH slightly above 7.4 cancer becomes dormant and at a pH 8.5 cancer cells will die while healthy cells will live." There is a food chart at essence-of-life.com that has a list of alkaline foods. Interestingly, probiotics are alkaline!
But, my mantra has always been "Theory is one thing, reality is another." Listen to your body. I just want to give people tools so they can try to shift their health away from sickness toward health.