displayed a significant moisturizing effect, as determined via use
of a Corneometer® CM 825 (Courage + Khazaka Electronic GmbH,
Germany), which was present up to two weeks after discontinuing
treatment.20 Effective moisturizing potential is important to
the photoaged population, as many of these patients will present
with xerosis and an impaired skin barrier. A safe, tolerable,
natural moisturizing agent with low irritant potential makes for
an excellent product to rapidly improve skin appearance.
Acai Berry
Acai is a berry that grows on the acai palm tree (Euterpe oleracea).
An evidence-based systematic review of acai by the Natural Standard
Research Collaboration, which summarizes efficacy data via
a validated, reproducible grading algorithm, concluded that acai
is a potent antioxidant.21 When acai polyphenolics were applied
to HL-60 leukemia cancer cells, cell proliferation decreased.22 The
antioxidant capability of acai berry is believed to be greater than
that of other berries. However, topical use of this supplement is
challenging given the risk of skin staining at high concentrations.7
Perhaps for this reason, there is a paucity of clinical research on
the use of acai berry for the treatment and prevention of photoaging.
A clinical trial evaluating the use of a dietary supplement
containing pomegranate, apple, and acai is seeking to evaluate erythema
inhibition, antioxidant concentration, skin hydration, skin
firmness, and skin texture in study subjects as compared to placebo.
The study has closed but the results are not yet available.23
Soy
Soy extracts are found in many cosmetic products. Lipids, lecithins,
and phytosterols enhance the normal skin barrier, while
isoflavones impart an antioxidant effect. A study of hairless mice
examined the effects of a soy isoflavone extract from soybean cake
composed of daidzein, genistein, glycitein, acetyldaidzin, acetylgenistin,
and acetylglycitin. Extract-treated mice and untreated mice
were exposed to UVB radiation. Treated mice showed a decrease
in UVB-induced death of keratinocytes and reduced erythema. The
skin of extract-treated mice also displayed less transepidermal
water loss and less apparent wrinkles. Many of these results were
deemed secondary to reduced oxidative stress.24
Serine protease inhibitors such as soybean trypsin inhibitor
(STI) and Bowman-Birk protease inhibitor (BBI) play a role in
pigment development. Wallo et al tested a formulation containing
nondenatured STI and BBI (as heat can inactivate these
protease inhibitors) on 68 females with Fitzpatrick skin types I
to III. All patients had moderately rough, blotchy, dull skin, mottled
hyperpigmentation and lentigines at baseline. The women
were randomly selected to apply either the active moisturizer or
the vehicle daily for 12 weeks. Both formulations contained SPF
30. Although both groups showed improvement from baseline,
the active moisturizer group exhibited enhanced performance
(P < 0.05) in improvement of overall texture, blotchiness, dullness,
fine lines, overall tone, and overall appearance.25
The use of soy is controversial among consumers, who worry
about an increased risk of endometrial and breast cancer
development. A recent Cochrane Review of the use of oral
phytoestrogens for menopausal vasomotor symptoms found
that phytoestrogens were not associated with an increased risk
of endometrial or breast cancer when used for up two years.
Unlike hormone replacement therapy, phytoestrogens did not
have an estrogen agonistic effect on the endometrium. Longterm
safety studies have not been conducted.26
Coffee Berry
Coffee berry is the fruit of the coffee plant (Coffee Arabica). It
contains polyphenols, including chlorogenic acid, anthocyanins,
quinic acid, and ferulic acid.16 Polyphenols are believed
to impart antioxidant as well as anti-inflammatory properties.
One patented formulation of coffee berry appears to have antioxidant
capacity that rivals green tea extract. In a clinic trial of this
specific formulation, patients treated actinic damage with a 0.1%
cleanser, a 1% day cream (containing also 7.5% octinate and 4%
oxybenzone), and a 1% night cream. Two-thirds of the patients
applied the products to their entire face, showing statistically
significant improvement in fine lines, wrinkles, pigmentation,
and overall appearance compared to baseline. One-third of the
patients applied the product to only half of their face, showing
statistically significant improvement in fine lines, wrinkles,
pigmentation, and overall appearance compared to the vehicletreated
half of the face.27
CONCLUSIONS
Patients are highly motivated to treat and prevent photoaging,
and may inquire as to the availability of natural ingredients to
treat rhytides, dyschromia, and actinic damage. As dermatologists,
we can provide guidance as to which ingredients may be
of benefit based on available scientific evidence. Mushrooms,
feverfew, green tea, licorice, olive oil, soy, and coffee berry all
display antioxidant properties. They are among the most scientifically
sound natural ingredients available to consumers.
Importantly, we can also help direct patient to those proprietary
formulations that have undergone clinical testing and demonstrate
safety and efficacy. Just because a product label lists an
ingredient does not mean that ingredient is stable or active
once it reaches the skin. It is important to remind patients that
the efficacy of a product relies on the stability of the ingredients,
their ability to penetrate the skin, and their capability to
act in vivo. This is a very exciting area, and as consumer interest
in natural ingredients continues to grow, the science behind
these ingredients grows stronger each year.
ACKNOWLEGMENTS
The authors would like to acknowledge Awadh M. Alamri MD,
Jayne Bird MD, and Brooke Walls DO, for their research and
contribution to the manuscript.