Tuesday, September 24, 2013

Alpha Hydroxy Acids & You

I’ve been on a serious project lately to improve my skin. For the past few years I've been content to wash my face when I felt like it. I bought moisturizers for my face because they were inexpensive and not because they benefited my skin beyond hydration (and even that was questionable). I was happy to do nothing about the onset of early wrinkles. I was lax at best when it came to SPF. I did nothing to treat the rosacea that has appeared on my cheeks after my babies were born. Basically, for the past few years, my philosophy was that less was more when it came to messing with my skin. And I was wrong. As a result of my inactivity I was left with large pores, slack skin, blackheads on my nose and chin, wrinkles beyond my years, uneven skin tone and dry and dehydrated skin.
I've woken up from the miasma of the past few years of neglect and have for months now been on a solid healthy skin routine. I'm using products designed for my skin type, in the way they're intended. I wash my face twice daily. I exfoliate gently every day. I'm using face masks, serums and quality moisturizers. My skin has come a long way. But there's still further to go. In the course of my research I have come up with recommendations for AHAs again and again, with the promise to improve my skin in ways no other products can. Alpha Hydroxy Acids are touted as the number one ingredient in beauty products to help skin rejuvenate itself.  
But chemicals are a scary thing, I'm sure anyone would agree. So I've put together some of the things I've found about AHAs that I think everyone should know. I hope this helps you on your own journey, and making the decision on when and which AHA you want to put on your own face. Disclaimer, I am not a medical professional or your doctor. The information I'm providing was gleaned from sources online (listed at the end). Use the information only in the way it's intended, as a brief overview of a complicated subject.
Let's Start With An Overview of Your Skin's Structure, Chemistry and How It Ages.

On top of our epidermis (the outermost layer of our skin) is a layer called our ACID MANTLE. This mantle is an imperceptibly thin viscous fluid. Its job is to maintain and protect the overall health of skin and hair. So what is the acid mantle made of? Secretions formed by sebaceous and eccrine sweat glands. Sebum (the oily substance produced by the sebaceous glands) and sweat, (the salty, watery mix produced by the eccrine glands) blend and are further acidified by secretions from normal flora of the skin (bacteria known as Staphylococcus epidermis). The normal acid mantle for both skin and hair ranges between 4.5 and 5.5.

Sunlight, diet, excessive sweating and the application of skin or hair products can all lead to disruptions in the acid mantle. Disruptions in the acid mantle are bad.

Underneath the acid mantle, the epidermis is protected by an external layer of tightly knit cells arranged like shingles on a roof. Any disruption to the acid mantle, meaning an elevated overall skin pH, interferes with this protective barrier, wrenching cells away from each other. This can result in dehydration, roughness, irritation and noticeable flaking. Skin is left defenseless and susceptible to further environmental damage.

As cells pull apart, any breaks become exposed, leaving skin more vulnerable to bacterial invasion. Under normal circumstances, bacteria not only have a difficult time penetrating through the shield-like structure of the skin but the acid mantle also creates a hostile environment for bacteria, which prefer an alkaline environment to flourish. A rise in pH plays mayhem with our natural infection prevention, further increasing the risk of infection. Once the pH exceeds 6.5, bacterial invasion increases dramatically, a loss of normal skin integrity results and a variety of skin disorders such as eczema, psoriasis and irritant contact dermatitis flare.

So why mention the acid mantle and skin's PH in a discussion about AHAs?

Because we have to consider the entire design of our skin and it's innate protective barriers when deciding what products to apply, how to treat conditions that already exist and how to treat our skin best for long-term health and beauty benefits. For example…

The use of a cleansing agent that contains a buffered glycolic acid or other alpha hydroxy acid (AHA) is a great way to keep epidermal cells lying tightly upon each other and skin glowing.

HOWEVER, as for hydration, if you already have parched, irritated skin, applying an acidic AHA product is not an option until you have soothed and settled with a "bland" moisturizing cream. After you've dealt with the healing phase, go into preventative mode and apply an "active" moisturizer, one chockfull of AHAs to help prevent dehydration, remove scale and maintain the acid mantle.

So what are AHAs?

AHAs are a group of organic carboxylic compounds. AHAs most commonly used in cosmetic applications are typically derived from food products including glycolic acid (from sugar cane), lactic acid (from sour milk), malic acid (from apples), citric acid (from citrus fruits) and tartaric acid (from grape wine).
For any AHA product you put on your skin to be effective, it has to penetrate into the skin where it can act on living cells. Bioavailability (the acid's ability to penetrate deeply into the skin's layers, influenced primarily by small molecular size) is an important factor in a compound's ability to penetrate the top layer of the skin. Glycolic acid, having the smallest molecular size, is the AHA with greatest bioavailability and penetrates the skin most easily; this largely accounts for the popularity of this product in cosmetic applications.

Once they're on our skin, what do AHAs do?

AHAs weaken the bond between living healthy cells just beneath the surface and the external layer of tightly knit cells that are mostly dead. This is a good thing, so that we can then more easily exfoliate the old dead skin cells. Then a new layer of tightly knit cells is formed on top that is thicker, stronger and better able to keep out bacteria and pollutants than the layer before it.
AHAs with greater ability to reach into the deeper layers of the dermis like glycolic acid, lactic acid and citric acid, used on photo-damaged skin, have been shown to produce increased amounts of mucopolysaccharides and collagen and increased skin thickness without detectable inflammation.
Glycolic acid works as an exfoliating agent because of its high acidity but easy solubility. When placed on the skin as part of an exfoliating cream or gel, it goes under the damaged upper layers of skin and destroys the 'glue' which holds dead skin to the surface. As this dead skin is chemically burned off, the other ingredients carry the individual flakes away and a water rinse neutralizes the remaining acid. The result is a much-smoother skin surface and a more youthful appearance. A secondary benefit is the product's ability to draw moisturizers into the newly-exfoliated skin surface. This is why cosmetic counters often sell a complete system of skin care; the rest of the alpha-hydroxy line contains moisturizers and neutralizers to counteract the corrosive actions of glycolic acid.
Cosmetic exfoliants and moisturizers containing glycolic acid may leave the user's skin especially sensitive to the sun, so many skin care experts recommend using a sunscreen after exfoliating with such products.
WebMD Describes AHA's to Be Likely Effective for:
·  Treating sun damage when applied to the skin in a cream or lotion, but alpha hydroxy skin peels do not seem to work for this use.
·  Treating dry skin when applied to the skin in a cream or lotion.

WebMD Describes AHA's to Be Possibly Effective for:
·  Acne when applied to the skin in a cream or lotion.
·  Acne scars when applied to the skin in a facial peel or lotion. Applying glycolic acid, an alpha hydroxy acid, as a facial peel or lotion seems to improve the appearance of acne scars. Applying 70% glycolic acid in a series of peels seems to work better than using 15% glycolic acid lotion daily. However, 15% glycolic acid lotion seems to be moderately effective in people who cannot tolerate facial peels.
·  Reducing pain and tenderness caused by fibromyalgia when a specific alpha hydroxy acid, called malic acid, is used in combination with magnesium.
·  Reducing the pigmentation associated with a skin disorder called melasma. Applying 10% glycolic acid as a lotion for 2 weeks followed by a facial peeling program using 50% glycolic acid every month for 3 consecutive months seems to reduce unwanted skin coloration in people with two of the three types of melasma, epidermal-type and mixed-type melasma. However, glycolic acid facial peels don’t seem to work for the third type of melasma, dermal-type melasma.
WebMD Describes There to Be Insufficient Evidence for:
·  Treating an inherited skin disorder that causes dry, scaly skin (like ichthyosis).
More evidence is needed to rate alpha hydroxy acids for these uses.

Alpha Hydroxy Acids and Chemical Peels
Some customers seeking a more complete exfoliation may opt for an AHA chemical peel. In general, a chemical peel involves a careful scrubbing of the skin followed by an application of a powerful AHA such as glycolic acid. Acid concentration levels in chemical peels can be as high as 50% or more. Even industrial suppliers of glycolic acid limit their concentration to 70%, so this is indeed a very powerful chemical process.
Quite often after a chemical peel, a patient's skin will look as if it were extremely sunburned. Several days of recovery are often necessary for a complete recovery from a chemical peel. Proponents of the process say that the process may appear dangerous or unsightly, but the results are worth the temporary discomfort.
AHAs in various concentrations are used in chemical peels. The concentration of the acid determines who can use it.
Consumer Level Products - AHA products sold to consumers must have a concentration of less than 10%.
In low concentrations, 5 - 10%, as is found in many over-the-counter products, glycolic acid reduces cell adhesion in the top layer of the skin. This action promotes exfoliation of the outermost layer of the skin accounting for smoother texture following regular use of topical glycolic acid (GA). This relatively low concentration of GA lends itself to daily use as a monotherapy or a part of a broader skin care management for such conditions as acne, photo-damage, wrinkling as well as melasma. Care needs to be taken to avoid irritation as this may result in worsening of melasma or other pigmentary problems. Newer formulations combine glycolic acid with an amino acid such as arginine and form a time-release system that reduces the risk of irritation without affecting glycolic acid efficacy.  The use of an anti-irritant like allantoin is also helpful. Because of its safety, glycolic acid at the concentrations below 10% can be used daily by most people except those with very sensitive skin.
Cosmetologist Level Products - Trained cosmetologists can use alpha hydroxy acid products that have a concentration of 20% to 30%. These chemical peels give results that are similar to microdermabrasion - erasing fine lines and giving the skin a smoother appearance with 1 to 3 applications. However, these treatments must be repeated every 3 to 6 months to maintain this skin appearance.
In higher concentrations, between 10 and 50%, its benefits are more pronounced but are limited to temporary skin smoothing without much long lasting results. This is still a useful concentration to use as it can prepare the skin for stronger glycolic acid concentrations (50 - 70%) as well as prime the skin for deeper chemical peels such as TCA peel (trichloroacetic acid).
Dermatologist Level Products - Doctors can use alpha hydroxy acid products that have a concentration of 50% to 70%. These treatments also erase fine wrinkles and remove surface scars, but the effects last longer - up to 2 to 5 years. The higher the AHA concentration used in a chemical peel, the more skin irritation occurs. At the 50% to 70% concentration, a person could expect to have severe redness, flaking, and oozing skin that can last for 1 to 4 weeks.
At highest concentrations, 50-70% applied for 3 to 8 minutes under the supervision of a physician, glycolic acid promotes slitting between the cells and can be used to treat acne or photo-damage (such as mottled dyspigmentation, melasma or fine wrinkles). The benefits from such short contact application (chemical peels) depend on the pH of the solution (the more acidic the product, or the lower the pH, the more pronounced the results), the concentration of GA (higher concentrations produce more vigorous response), the length of application and prior skin conditioning such as prior use of topical vitamin A products. Although single application of 50 - 70% GA will produce beneficial results, multiple treatments every 2 to 4 weeks are required for optimal results.[8] It is important to understand that glycolic acid peels are chemical peels with similar risks and side effects as other peels. Some of the side effects of AHAs chemical peeling can include hyper-pigmentation, persistent redness, scarring, as well as flare up of facial herpes infections ("cold sores").

Choosing an Alpha Hydroxy Acid
Alpha hydroxy acids are found in a variety of skin care products including moisturizers, cleansers, eye cream, sunscreen, and foundations. Here are some guidelines to use when trying to decide which alpha hydroxy acid formulation to use:
·         It is best to pick one product that contains the proper formulation of alpha hydroxy acid to use as your exfoliant, and then choose other skin care products or cosmetics that don't contain alpha hydroxy acids to reduce the likelihood of skin irritation.
·         Using an alpha hydroxy acid in a moisturizer base may be the best combination of products.
·         Cleansers containing alpha hydroxy acids are least effective when hoping for anti-aging effects because the alpha hydroxy acid must be absorbed in the skin to work. Cleansers are washed off before this absorption occurs. Having said that, they do tighten the cells on the top layer of the epidermis which benefits the skin's hydration and keeps out unwanted bacteria.
·         At this time there are no effective products that combine alpha hydroxy acid and sunscreen, because sunscreen is not stable at the pH required to make the alpha hydroxy acid effective.
·         Sunscreen MUST be applied liberally when using an alpha hydroxy acid product. The sunscreen should have an SPF of at least 15 for UVB protection and contain avobenzone, titanium dioxide, or zinc oxide for UVA protection.
·         Consumer level Alpha hydroxy acids work best in a concentration of 5% to 8% and at a pH of 3 to 4.
·         Unfortunately, cosmetic manufacturers are not required to provide concentration information on the label. As a general rule of thumb, having the alpha hydroxy acid listed as the second or third ingredient on the list makes it more likely it contains the proper concentration.
·         The only way to know for sure the pH of a product is to test with a pH strip.  

AHA Side Effects & Safety
Alpha hydroxy acids at a concentration of 10% or less as a lotion or cream are LIKELY SAFE for most people when applied to the skin appropriately and as directed. In some people, alpha hydroxy acids can make the skin extra sensitive to sunlight. Be sure to use a sunscreen while using alpha hydroxy acid products.

Alpha hydroxy acids can also cause mild skin irritation, redness, swelling, itching, and skin discoloration.

Facial peels, lotions, and creams with a concentration greater than 10% should only be used under the supervision of a dermatologist. Facial peels can cause moderate to severe skin irritation, redness, and burning. Facial peels left on the skin for periods longer than recommended can cause severe burns to the skin.

According to WebMD:  Special Precautions & Warnings::
Pregnancy and breast-feeding: Alpha hydroxy creams at a concentration of 10% or less are LIKELY SAFE when applied to the skin during pregnancy and breast-feeding. But don’t take malic acid (the form of alpha hydroxy acids that is generally taken by mouth). Not enough is known about the safety of malic acid during pregnancy and breast-feeding.

Sensitive skin: Alpha hydroxy acids can worsen skin conditions by causing skin irritation and removal of the top layer of skin cells.

The Difference Between Alpha and Beta Hydroxy Acids
There is only one beta hydroxy acid - salicylic acid.
The main difference between AHA and beta hydroxy acid is their lipid (oil) solubility. Alpha hydroxy acids are water soluble only, while beta hydroxy acid is lipid (oil) soluble.
This means that beta hydroxy acid is able to penetrate into the pore which contains sebum and exfoliate the dead skin cells that are built up inside the pore. Because of this difference in properties, beta hydroxy acid is better used on oily skin with blackheads and whiteheads and is often used to fight acne.
AHAs are better used on thickened, sun-damaged skin where breakouts are not a problem.