Glycolic acid also known as a-hydroxy acid is a naturally occurring alpha hyroxy acid,AHA, which is colorless, odorless and is commonly from plants mostly sugar cane crops, sugar beets and pineapple. It also has the property of being highly soluble in water.  It is one of a whole group of acids known as alpha hydroxyl acids or AHA's. The family of acids are citric acid from citrus fruits, tartaric acid from grapes,  malic acid from apples and lactic acid from milk.  Each are similar in molecular structure but each get progressively bigger with the smallest molecular structure starting at glycolic acid, next largest lactic acid, malic, tartaric and finally the largest being citric acid.. Glycolic acid is easily used in compounds such as lotions, gels, creams, serums and peels with its chemical characteristics unlike its earlier used substances and its small molecular structure allow it to produce impressive skin changes

Since the early 70's  the use of AHA's has started to hit the clinical setting skin care arena for the initial primarily use in psoriasis to break down the heavy white plaques of dead cells. It was found to improve the condition, soften plaques and enhance other treatments penetration. This then sparked the interest for further use in areas where exfoliation was needed.  The AHA's have been increasing used in the skin care beauty arena with the most effective being glycolic acid due to its smallest molecular size.  It has been used in various lotions , gels cleansers and serums and peels to exfoliate the skin and with it s small size was found to be effective in going into the deeper layers of the skin down into the dermis as well as the epidermis and cause actions production of collagen as well as work on the lower epidermis to calm down pigment cell production and lighten skin from conditions such as melasma.

It has been used over the last twenty years in clinical settings in strengths from 3 to 70%(full strength) and tested and found go be "generally regarded as safe" by the FDA, after years and years of use with little reported side effects outside of the irritation it can produce to skin in higher concentrations or use on skin which has some change in the integrity.  The U.S. Food and Drug Administration(FDA) has regarded the use of products for consumer  as safe and OTC in solutions up to 10 to 20 percent. Higher percentages are used in clinical settings with strengths from 20 to 70 percent in chemical peels which are used in treatment of wrinkles, fine lines, acne scarring, pigmentation and destruction of precancerous lesions of the skin, actinic keratosis as well.  Chemical peels of higher strengths are recommended to be performed by licensed professionals and medical professionals.  Lighter lower concentration peels can be safe to be used for home peels.

Glycolic home peel programs have proven to be very successful as well due to the regular stimulation of cells from the top layer of the epidermis, known as the stratum corium to the deeper layers of the dermis where collagen and moisture molecules are housed. 

Previously chemical peels were predominantly used with solutions of TCA (trychlorcetic acid) which produces a complete destruction of tissue or a frosting.  The skin then has to heal from the scabbing and abrasions to produce the smoother skin. Repeated use of glycolic at different percentages showed the skin did not have to be injured in order to produce results of true skin restoration or rejuvenation. Enhanced collagen production occurs, increased moisture, less clumping of pigment cells clear clean pores reveals glowing supple elastic plump radiant skin.Lower percentage deeper treatments of twenty to thirty percent peels were showing the same results or better than the strong peels without the adverse side effects of potential hyperpigmentation and long term healing down time.  It should be noted that higher percentages and misuse can still cause injury to skin . Health care professionals and medical esthetician  should be performing the higher percentages.

As noted lower percentages of 10-15% can be used for mini home glycolic peels to give the skin the boost it needs regularly as well as a daily regime of glycolic cleansers , lotions and creams or gels. 

Other properties of glycolic acid outside of its highly effective ability to exfoliate dead cells ranging from the top dulling layer to knees, elbows, psoriasis, seborrhea dermatitis , dandruff, and seborrhic keratosis.  Glycolic acid has been known to have properties of hygroscopic meaning the ability to extract moisture from the environment meaning the skin will have more inherent internal moisture and look and feel more plump and supple.  Skin biopsies after regular use and glycolic peels have shown to increase molecules known as glycosaminoglycans or GAGS, in the lower layer of the skin the dermis.

Glycolic acid has been known for its great bio-availability with its small molecular structure and its ability to act on layers from the top dead layer to the lower dermal layer. It is known to be the "wonder substance for anti aging and acne" and more.  

Studies have also remarkable to show the increase of collagen production , again due to its small molecular size, in the dermis  Collagen is a protein housed in the dermis of the skin which helps give the skin plump supple structure and support thus improving wrinkles and sagging skin. It should be always recommended that one stay out of the sun after treatments for the reason the skin is sensitive but also knowledge of the heavy sun exposure will rapidly accelerate and enhance aging wrinkles , pigment  and sagging skin as well as the use of tanning beds..  Cellular changes occur and thus can set the stage for skin cancers ranging from pre cancers to more serious life threatening cancers known as Melanoma. Dermatologist recommend sun blocks used with regular exposure to the sun, especially those containing titanium dioxide and zinc oxide( now available in clear) for beauty and sport purposes.

Since glycolic has the ability to exfoliate by actually breaking the lipid bonds or glue of the dead skin cells it has been know to the "dis-solver of the glue that holds the cells together' thus gently lifting off this dead layer leaving a brighter, clearer, softer glowing skin.  Dead cells or stratum corneum are regularly, daily produced and increase with   age.  One notices the skin of a child is soft and glowing due to their inherent little to null  dead layer.

Glycolic acid with its property of small molecular size and exfoliation properties it also is known to go into the pore and "unroof" the pore or oil and sebum which are there and ready to create the perfect environment for bacteria and future acne lesions ranging from blackheads, papules , pustules and cysts. Regular use of glycolic reduces the number of lesions and rate of healing and resolving much quicker. As mentioned the use of glycolic acid products also treats pigmentation which can occur after the injury to skin of an acne lesion leaving dark spots or what is know as post inflammatory hyper-pigmentation or PIH. The pores have the opportunity to become refined or smaller since the dead layer is not regularly clogging them.  The skin will feel a sensation of breathing.  Dermatologist and skin care professionals have also noted the increase in penetration of other substances placed on the skin in the treatment of acne such as topical antibiotics which work much more effectively with the barrier eliminated. Also topical vitamin therapy such as Vitamin A used for treatment of acne and increasing elasticity, as well as psoriasis , rosacea and stretch marks can absorb with ease.  Other important vitamins used in the treatment of aging, acne and pigmentation is the use of Vitamin C, especially in the form of Mag C, Magnesium ascorbyl phosphate, since it  does not oxidize and has great potential for making the precursors of collagen, known as proline, thus assisting in treatment of wrinkles.  Other topical vitamins of importance are Vitamin E and Niacin amide or B3 which can enhance collagen production , help skin immunity, diminish darkened areas as well as antibacterial effects.

Acne clients are recommended to have regular treatments of higher percentages of glycolic acid with the guidance of professionals if advanced stages.  Many safe over the counter options are available for regular home use such a s home peels, glycolic cleansers, glycolic gels and toners all assisting in the reduction of acne lesions, and enhance of healing and less chance of scarring. If scarring is present regular treatments should be scheduled to give the skin bolus of the glycolic to enhance the skins own ability to produce the collagen cells to smooth out the acne scars.

The skin likes to be at a normal pH of (4.5-5.5) thus glycolic acid helps to normalize the level of pH which can be disturbed by sun, diet, hormones and detergents. Regular use of glycolics assists in pH balance and overall health of the skin

The whole movement and use of glycolic acid in products for treatment of aging and acne have started a whole new industry named advanced skin care or Cosmeceuticals. These products truly have the ability to change skin structure thus seeing dramatic results.  The key is to seek products with the active ingredient in sufficient quantity  and quality to actually work. Some products , since costs of active ingredients are high, use insufficient amounts, or diluted with too many other ingredients to denature or interfere with the action of glycolic.  It has been know for many manufacturers to give a percent of the glycolic and then will use a buffering agent, hydroxide thus making the real active percentage unknown and possible less effective.

Overall the ability to slow down aging and restore and repair damage is possible with the regular use of glycolic acid products, treatments

/peels.  Emphasis is placed on quality and integrity of product ingredients.

Risks and side effects

If skin integrity is changed such as by active eczema or skin rashes glycolic acid product usage should take a break.  Skin integrity can also be changed by active scratching an area from common allergic conditions or dry skin.  Also if one picks their skin or acne lesions it can sometimes cause the products or treatments to go to deeper layers which may cause irritation.

It is known when used in high concentrations 35%-70 to "frost" the skin which a professional should be advising the treatment program.  Frosting can cause hyper-pigmentation on some skin types . Skin treatments in general should be avoided with active infections such as impetigo or herpes simplex(cold sores) until completely resolved.

Overall the use of glycolic acid products and treatments have changed the way skin aging and acne treatment options available compared to the past decades. Greater understanding and education to the consumer  continue to improve and proliferate to the consumer and increase availability for the future hanged the options available to slow down aging and truly rejuvenate(change structure) when used regularly and with guidance.  The results  are on all skin types ranging from fair  freckled blue eyed to dark pigmented skin are proven safe and effective. Starting with puberty  glycolic acid products and treatments can  be used for those early signs of acne.  Early pregnancy when the skin is going through its sensitive hormonal changes is recommended to not start a treatment program for melasma or pregnancy mask until childbirth since the hormones continue to increase until then thus making it difficult to treat.

Written by Marcia Fosnaugh Avis. All rights reserved