pH friendly (pH balanced): At -417, pH friendly products means the pH level is between 4,5 and 7. The acidic layer helps your skin retain moisture and keeps germs out.
The pH scale ranges from 1 to 14, with 7 considered “neutral.” The lower numbers are acidic, while the upper levels are considered alkaline, or nonacidic. A healthy skin pH is more on the acidic side. With more acidity, the skin can combat harmful microbes that might increase the aging process.
Skin pH varies depending on the area of your body. Lesser exposed areas tend to maintain their natural acidity. This is unlike your face, chest, and hands, which tend to be more alkaline. These differences exist because the latter areas of skin are more exposed to the elements.
Other factors that can affect skin pH include:
acne
air pollution
antibacterial products
change in seasons, with different humidity levels
cosmetics
detergents
antibacterial soaps and gels
sebum/skin moisture
sweat
tap water
too much sun exposure
too frequent washing of your skin