|| Beauty Care Business and Professional Network
U. S. Food and Drug Administration
July 3, 1997
Alpha Hydroxy Acids in Cosmetics
Cosmetics that contain alpha hydroxy acids (AHAs) have become widely used in
recent years despite many unanswered questions about their safety. Recently, a
study sponsored by the cosmetics industry indicates that these products may make
users more sensitive to sunlight and especially to the ultraviolet (UV)
radiation component of sunlight. UV exposure can damage the skin and at high
doses, especially over a long period, can cause skin cancer. FDA is currently
evaluating this study and is pursuing additional studies that will make sure
these products are safe for consumers to use.
It is wise to use sun protection before going into the sun (daylight).
Adequate sun protection includes: wearing a hat with a brim of at least four
inches, wearing lightweight sun protective clothing, including long sleeves, and
applying a sunscreen with an SPF (or Sun Protection Factor) of at least 15.
Sunscreens should be reapplied after excessive sweating or swimming. It is
especially important to use effective sun protection if you are going to the
beach and will be exposed to high levels of UV radiation.
The recent study makes these sun protection precautions even more important
if you use AHA-containing products. It is important to use sun protection,
including a sun screen, if you use an AHA product, even if you
haven't used the product that day. If the AHA that you're using contains a
sunscreen, it is suggested that applying an additional sunscreen (SPF 15)
product before going into the sun will be beneficial. Even though your AHA
product may contain sunscreen, it is primarily a skin treatment product--not a
means of sun protection. If you use the AHA at bedtime, be sure to apply an
additional sunscreen product in the morning before going into the sun.
The agency has received about 100 reports of adverse effects with AHA
products, ranging from mild irritation and stinging to blistering and burns. If
you usually have sensitive skin, FDA advises you to test any product that
contains an AHA on a small area of skin before applying it a to large area. If
you use cosmetics with AHAs and experience skin irritation or prolonged
stinging, FDA advises you to stop using the product and consult your physician.
Products with AHAs are marketed for a variety of purposes: to smooth fine
lines and surface wrinkles, to improve skin texture and tone, to unblock and
cleanse pores, to improve oily skin or acne, and to improve skin condition in
general. It is important to follow the use instructions on the label. Do not
exceed the recommended applications. It is not recommended that
AHA-containing products be used on infants and children.
To find out if a cosmetic contains an AHA, look on the list of ingredients
all cosmetics must, by law, have on their outer packaging. AHA ingredients may
be listed as:
Of these, the most frequently used in cosmetics are glycolic acid and lactic
- glycolic acid
- lactic acid
- malic acid
- citric acid
- glycolic acid + ammonium glycolate
- alpha-hydroxyethanoic acid + ammonium alpha-hydroxyethanoate
- alpha-hydroxyoctanoic acid
- alpha-hydroxycaprylic acid
- hydroxycaprylic acid
- mixed fruit acid
- tri-alpha hydroxy fruit acids
- triple fruit acid
- sugar cane extract
- alpha hydroxy and botanical complex
- L-alpha hydroxy acid
- glycomer in crosslinked fatty acids alpha nutrium (three AHAs).
If you have purchased a product whose outer packaging has become separated
from the product and you are unsure whether it contains AHAs, call the
manufacturer, whose phone number may be listed on the inner packaging.
AHA products cause exfoliation, or shedding of the surface skin. The extent
of exfoliation depends on the type and concentration of the AHA, its pH
(acidity), and other ingredients in the product. Most cosmetics sold to
consumers contain AHAs at levels up to 10 percent. It is FDA's understanding
that products with AHA concentrations of 20 percent or higher are used by
trained cosmetologists for salon "mini-peels."
In studies conducted by FDA on the absorption of AHAs through the skin, the
AHAs tested were readily absorbed into the skin at varying rates. The most rapid
absorption occurred with AHAs having lower pHs (higher acidity).
FDA issued a report in February 1996. "Effects of Alpha Hydroxy Acid on
the Skin" concluded that additional scientific investigation was needed to
establish the safety of these products.
The recent report linking AHAs to increased UV sensitivity was sponsored by
the Cosmetic, Toiletry, and Fragrance Association. The results were reported at
a December 1996 meeting of the trade group's Cosmetic Ingredient Review Panel
(CIR), which began reviewing the safety of AHAs in 1994.
The panel concluded at its December meeting that AHAs are "safe for use
in cosmetic products at concentrations less than or equal to 10 percent, at
final formulation pHs greater than or equal to 3.5, when formulated to avoid
increasing the skin's sensitivity to the sun, or when directions for use include
the daily use of sun protection." For salon use products, the panel said
that the products are "safe for use at concentrations less than or equal to
30 percent, at final formulation pHs greater than or equal to 3.0, in products
designed for brief, discontinuous use followed by thorough rinsing from the
skin, when applied by trained professionals, and when application is accompanied
by directions for the daily use of sun protection."
These conclusions were made final at a June 1997 meeting of the CIR panel in
spite of serious safety questions submitted by a consumer group and a major
manufacturer. FDA is reviewing these CIR conclusions, as well as the other
available data about these products. Consumers should be aware that AHA
concentration and pH are generally not noted on all products. (FDA does not
require it.) However, the information should be available from the manufacturer.
Cosmetics manufacturers are not required to submit safety data to FDA before
marketing products, although they bear the responsibility for manufacturing safe
Consumers should report any adverse reactions, such as irritation or sun
sensitivity, associated with the use of AHAs to their local FDA office, listed
in the Blue Pages of the phone book, or to FDA's Office of Consumer Affairs at
Remember: The Best Wrinkle Preventer is Sun Protection.