Skin cells are continuously dying and re-generating.
Cells on the surface rub and flake off steadily, and are continuously replaced with new ones. About every 30 days your body produces a totally new epidermis. [BBC link: http://www.bbc.co.uk/science/humanbody/body/factfiles/skin/skin.shtml]
Exfoliation involves the removal of the oldest dead skin cells on the skin’s outermost surface.
This method of exfoliation is effective and intensive. It should be practiced with caution around the sensitive skin areas such as the face and neck. Physical exfoliation can be a great additive to a weekly skincare regime, but exercise caution if you have acne, dermatitis, dry skin, eczema, psoriasis, sensitive skin, or under the age of 30.
NOTE: A chemical ingredient does not equal a toxic ingredient. Remember, everything is a chemical. Water has a chemical formula, as does your tears, as does ammonia, as does anti-freeze. It is important to understand how to differentiate between toxic chemical ingredients and non-toxic chemical ingredients.
Are great for anti-aging, and exfoliating the top layers of your skin (epidermis) helping to promote growth of younger skin by way of the dermis (second layer)
Naturally occurring alpha-hydroxy acids can be found in sugarcane (glycolic acid), milk products and tomato juice (lactic acid), bananas, apples, nectarines, pears (malic acid), citrus juices and fruits (citric acid), and grapes, apples, tamarind (tartaric acid).
Do you ever come across a do-it-yourself recipe calling for bananas and yogurt? The basis of many of these DIY masks are optimizing on naturally occurring AHAs to help exfoliate the skin and promote new skin cell regeneration.
While there are several types of BHAs, there is only one commonly found in skincare products, and that is salicylic acid. It is commonly used for acne prone skin and treating black heads. Salicylic acid penetrates the skin’s natural oils (sebum), thoroughly cleaning out clogged pores that cause whiteheads and blackheads.
BHAs are found naturally in fresh fruit (berries, pineapple, papaya), yogurt, wintergreen leaves, sweet birch and some other plants. Structurally, BHAs appear similar to AHAs, and have similar activities on the skin. However, AHA’s are more commonly used for epidermal exfoliation and anti-aging ingredients, and BHA’s are more commonly used for preventing acne eruptions and smoothing the skin.
Now when you read ingredients on skincare products and you recognize citric acid, malic acid, and salicylic acid you can understand WHY those ingredients are there.