Acid yielding high protein foods leech calcium and magnesium from the bones to maintain the body pH. These get deposited in the kidneys in the form of stones.

Also, bacteria that cause urinary tract infection, multiply freely in an acid medium. Consuming alkaline foods, like fruit, help make the urine alkaline. This prevents bacterial growth. Urinary tract infections can usually be controlled by consuming a largely fresh fruit and juice-based diet for a few days, as this will serve to make the urine more alkaline.