You have probably heard that good cleansers won't alter the skin's natural alkaline balance, or pH. The pH of a substance is a measure of its acid or alkaline content. We rank pH on a scale of 0-14, with pH 7, the natural acidity of water, being neutral. Further below 7 a pH value is, the more acidic the substance; the higher above 7, the more alkaline. Read more of this post