Did you know the largest organ of your body is the skin?
The skin and the various glands, nerves, and sensors connected with it form a complex organism. Your skin is your primary defense against many on-going assaults to your body's well-being and immunity. These functions may be classified as protective, sensory, respiratory, both heat regulating, & secretory. The skin protects the body from injuries from without and also acts as a guard against a too rapid loss of the liquids and heat from within. Thus the skin protects the muscles, nerves, and blood vessels from such dangers as might be caused by blows or pressure, as well as from the injurious effects of high and low temperatures.
As the skin forms a sensory covering to the body, it conveys the sensations of pressure, temperature, and pain so that the body may adapt itself to changes in its environment. Another important function of the skin is heat-regulation. The skin is aided by the two million or more sweat-glands which are distributed over almost the entire surface of the body. The skin and the sweat-glands together serve to keep the blood at an even temperature, either by giving off heat or in preventing this process in case the outside air is too cool.
The acid mantle is the outermost layer of skin and act as a protection layer which protects the surface of the skin against bacteria, viruses and other potential contaminants. It is formed by the mixture of sweat and sebum secretion, and includes naturally occurring enzymes, probiotics, defensens, white blood cells, and anti-inflammatories. The acid mantle in normal skin is at a pH between 4 to 5.5. The skin is quite acidic. Every time you use the wrong products on the skin, it changes the pH, and it can take 6+ hours to set it back to its protective, natural state. Think about that when using bar soap (which is VERY alkaline, and has a pH of about 11 or more); or stripping toners, which are more acidic than the skin.
Most of us use soap and water to clean our faces without realizing that this may not be beneficial to us. Soapy water is highly alkaline (with a pH of 12) while our skin is naturally acidic (with a pH of approximately 5). Soapy water is commonly used to clean our faces because it removes the natural oils from the skin. While this leaves our skin with that "clean feeling," soap is actually neutralizing our skin's acid pH thereby stripping away our natural defense systems. Particularly for those of us that wash our faces 2, 3, or more times a day because of a problem condition like acne - stripping away the acid mantle can actually worsen many conditions. Similarly, it is important for us to know the pH of any cleansers, moisturizers, makeup and other products we use so that we don't alter or remove the protective oils and change the acid mantle of our skin. If you're improperly caring for your skin, and you 'wash' 2x daily, the skin barely has time to catch-up and re-set its correct pH. This sets-up a dangerous cycle of inflammation (which may or may not be visible). The pH scale is an algorithm - for every number you go up (alkaline), it increases the alkalinity 100 fold. Every number you go down (acid) one point, the acidity becomes 100 times stronger. If the acid mantle is stripped off the skin, it becomes vulnerable, and pathogens can attack and infection may occur.
The Acid Mantle has the following functions:
Prevent over-evaporation to normalize skin's moisture level and protect skin against the penetration of free radicals, and damage from extrinsic pollutants.
Maintain Skin pH Balance
Maintaining the balance of skin pH is very important in regulating the skin's protective functions: suppleness, elasticity, slow-down aging, aid smoothness via hydration and sebum (oil) production.
Resistance to Infection
The acidity of acid mantle is able to kill and prevent pathogens (germs) from growing, helping protect the skin from problems such as acne, eczema, inflammation, and other skin diseases.