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Of the topical preparations available for the treatment of sun-damaged
skin, other than tretonoin, only glycolic acid has been shown to
reverse the process of photoaging, David Bank, M.D., said at Academy
‘99.
Glycolic acid is in the alpha hydroxy acids (AHA’s), a group
of naturally occurring substances derived from sugar cane. In addition
to helping to remove dead surface skin cells and acting as a stimulus
for skin renewal, glycolic acid stimulates cultured fibroblasts
to produce fresh collagen, said Dr. Bank, director, The Center for
Dermatology, Cosmetic and Laser Surgery, Mt. Kisco, N.Y. “This
may be one of the mechanisms by which it has an anti-aging effect.”
Glycoloic acid is used for in-office peels and is an ingredient
in many at-home products. Two recent offshoots of glycolic acid
are the amino fruit acids and Refinity from Collagen Corp. Both
were developed in response to the skin sensitivity and irritation
experienced by some users of traditional glycolic acid, especially
with the concentrations used during in-office treatments.
Amino fruit acids are derived from naturally occurring amino carboxylic
acids found in the seeds and buds of sugar cane. They also have
anti-aging and anti-inflammatory properties, and are less irritating
because of the presence of the amino group on the molecule.
Through a proprietary action, amino fruit acids are converted
to tricarboxylic acids, which supposedly have an antioxidant effect
and increase moisture retention in the skin. “For many patients
who cannot tolerate 50 to 70 percent glycolic acid yet wnat the
benefits of these higher concentrations, we see clearly that the
amino fruit acids offer similar benefits but without the irritation,
“ said Dr. Bank.
Refinity contains the ingredient strontium nitrate at concentrations
of 20 to 30 percent, which has been shown to significantly reduce
the irritation associated with glycolic acid.
Topical Vitamins: Myths Debunked
Topically applied vitamin C has been shown to function as an antioxidant
by stabilizing free radicals generated after ultraviolet light exposure
and regenerating vitamin E from its radical form, Dr. Banks said.
Levels of vitamin C in the skin do not increase by taking large
amounts orally. Topically delivered vitamin C requires at least
a 10 percent concentration and a pH of 2 to 3 to achieve tissue
vitamin C levels 20 to 40 times greater than in normal skin.
The utility of topical vitamin C appears tp be as an enhancement
of sunblock. Topical vitamin C becomes an inherent part of the skin.
It is fully protective for as long as three days after it is applied.
As an adjunct to sunscreen, vitamin C plays a role in squelching
UV radiation that gets past your sunscreen. Most topical vitamin
C preparations are stable for 3 to 6 months and degenerate in the
presence of UV light.
Read a Guide to Care & Causes
of Sun-Damaged Skin
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