Licorice
Licorice is a popular botanical ingredient
with a long and rich history. A candy-store
favorite, the flavor associated with licorice
actually is anise, which confectioners traditionally
combine with licorice. The genus Glycyrrhiza contains about 20 species, covering the
Americas, Australia, Asia and Europe. Today, there is
controversy surrounding the consumption of licorice in
large amounts as a medicinal herb, but since licorice candies
contain little if any of the actual licorice essence,
candy lovers are probably in no danger. Recent studies have shown that licorice
extract, rich in antioxidant glabradine
fractions, inhibits melanin biosynthesis as
well as scavenges free radicals when used
as a topical ingredient.
Licorice root has been chewed, stewed and brewed by
humans both as medicine or simply for its earthy,
extremely sweet flavor for at least a thousand years, possibly
more. King Edward I of England placed a tax on the
import of the popular root in 1305 to finance the repair of
London Bridge; Napoleon’s licorice-chewing habit supposedly
is what turned his teeth black. Extremely popular
in centuries of Chinese herbal formulations, licorice is
used there today as an antacid, as well as in many other
applications. Some licorice aficionados even make the
claim that licorice stimulates adrenal activity and is helpful
in restoring and maintaining mental acuity. Licorice
salve is also marketed as treatment for herpes lesions and
is an ingredient in many hair-loss products.
Licorice and its chemical components have been investigated
for many uses as a topical skin care ingredient.
Some of the earlier work has demonstrated that glycyrrhetinic
acid and glycyrrhizin (primary components in
licorice) are even more effective than topical cortisone in
treating eczema in children. These compounds were
shown to inhibit the anti-inflammatory response of skin
reddening and itching triggered by the arachidonic acid
cascade. Glycyrrhizinic acid has been shown to reduce
edema or swelling of tissues and have anti-viral activity.
Clinical studies have shown that topical application of
licorice components, including the acids, can help reduce
the healing time and pain of both oral and genital herpes
lesions. More recent studies have shown that licorice
extract, rich in antioxidant glabradine fractions, inhibits
melanin biosynthesis as well as scavenges free radicals
when used as a topical ingredient. For this reason, glycyrrhiza
glabra and glycyrrhetinic acid are sought out as
ingredients in skin care products, especially those dealing
with hyperpigmentation issues.
Licorice, when combined with Szechwan pepper,
lavender and cucumber, has been shown to ease the solar
sting and inhibit the formation of sun damage-triggered
dark spots. Likewise, the new breed of hydroquinone-
free skin brighteners, intended to reduce hyperpigmentation
without irritation, employ licorice along with other botanical brightening agents such as bearberry, rice, kiwi
and mulberry (this is a particularly effective combination
when left on the skin overnight). For environmentally
sensitized skin, licorice is effective when suspended in
liquid form, ideally in combination with Canadian willow
herb, raspberry and cucumber, and misted lightly
over the face to reduce irritation and stress, and to protect
skin from further environmental assault. When combined
with other classic calming agents such as allantoin
and oatmeal, licorice becomes a soothing component in
non-soap (syn-det) cleansing bars (vs. traditional bar
soaps, which are highly alkaline and often perfumed with
irritating synthetics). When teamed with concentrated
vitamins, comfrey and burdock, licorice helps desensitize
irritation and reduces redness in the form of a “recovery”
mask for stressed-out skin. The applications for licorice
as a topical anti-inflammatory are nearly as numerous as
the skin conditions that are treated with it, supporting at
least the external portion of centuries of folkways and
naturopathic uses.
The future of herbs
In terms of their use for skin therapists, do botanicals have a place among the new pentapeptides and other state-of-the-art discoveries being crafted in the lab? Absolutely. So often, people want to draw a distinction between a botanical or “natural” source and a “chemical” source. But the truth is, everything is chemical. The essence of a flower petal is chemical, and so the distinction does not serve us any longer.
Botanicals and herbs are powerful. Some are potentially
dangerous, particularly if ingested. It is naïve to think that
everything that emanates from a plant source is benevolent,
and somehow gentler than a manmade source. The
good news is that we are now uncovering the scientific
properties of petals, leaves, barks, roots, seeds, fruits and
pollens, and what they represent in terms of enhancing
human health. Without a doubt, as science replaces cherished
home remedies and recipes, a few of granny’s cures
will fall by the wayside as no more than quaint folk practice.
However, we have only begun to understand the
potential of herbs and plants to heal, giving us more reason
than ever to protect Earth’s botanical resources. Our
very survival depends on it.
Author of this article, Diana Howard, Ph.D., is the vice president
of technical development for Dermalogica
and The International Dermal
Institute and has a Ph.D. in biochemistry
from UCLA. Howard has worked
in research and development, and marketing
for Redken, Zotos and La Costa
Spa Products.
Call her at 1-(800) 611-SKIN or visit www.dermalogica.com/professional.