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Women’s Health
T he S kinny
You may be surprised to learn
that the largest organ in our
body is our skin. Weighing on
average six pounds, our skin
provides a myriad of critical
functions and is involved in a
wide variety of jobs that affect
the entire body.
With so many jobs to do, the
skin is understandably a complex structure (see figure below).
It is made up of two layers: the
outer layer, or epidermis, and
the inner layer, or dermis. The
epidermis is thinner than the
dermis and contains several
different types of skin cells. The
majority of cells in the epidermis
are squamous cells (flat, scalelike cells also called keratinocytes) that form the most exterior layer.
As our body’s outer covering,
the skin is protective, shielding
us from cold, heat, sunlight,
infections and injury. Yet, more
than simply a protective covering, our skin acts as a barrier,
protecting our internal organs
from environmental toxins and
invading organisms.
Our skin also regulates our
body temperature as it orchestrates the process of perspiration, and is involved in the
elimination of wastes from the
body. On the other hand, our
skin is also important for absorption, as it retains water and
ushers essential nutrients and
molecules back into the body.
Some medications and hormones are absorbed through
the skin, then circulate throughout the body and our internal
organs. Finally, skin plays a
crucial role in absorbing UV
light from the sun, and then
converting sunlight into vitamin D, an essential element for
good health.
O ur S kin
on
Just below the squamous cells
are round basal cells, which
constantly divide and rise to the
outer surface of our skin where
they die and then slough off.
Interspersed between the basal
cells are specialized cells called
melanocytes whose main role
is to produce a molecule called
squamous cells
(keratinocytes)
basal cells
melanocytes
epidermis
sweat
gland
dermis
oil
gland
nerve
fiber
blood
vessel
hair
follicle
fat
cell
melanin, or pigment, which
gives the skin its color. Melanin
is also important as it absorbs
UV radiation from the sun and
protects the skin from too much
sun exposure.
The inner dermis of the skin
contains a variety of structures
including blood vessels, hair
follicles, nerve fibers, lymph
ducts and glands. These glands
produce sweat, which helps to
regulate body temperature, as
well as sebum, an oily substance that keeps the skin from
drying out. Both sweat and
sebum reach the skin’s surface
through openings called pores.
The dermis also contains two
types of fibrous proteins: collagen, the most abundant protein
in the skin, and elastin. Collagen provides rigidity and support to our skin while elastin,
with its ability to coil and recoil
like a spring, gives the skin its
elasticity.
Over time, aging and environmental factors contribute to our
body’s diminished ability to
produce collagen and elastin,
causing skin to wrinkle and
sag.
In Hormone Replacement Therapy
and the Skin, Dr. Allesandra
Graziottin describes the skin
as our “multisensory identity
Continued on Page 2
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card.” She writes, “The skin
maintains life-long the written
and visible memory of our life. Its
characteristics and texture reveal
our age and life-styles—particularly related to sun exposure and
skin care, but also to the quality
of nutrients and stress levels—
and the quality of our health.”
“The skin maintains life-long the written
and visible memory of our life.”
Indeed, simply by looking at a
person’s skin, we may be able to
learn quite a bit about who that
person is. Certain features such
as wrinkles and scars, and their
appearance as well as location on
the body, often reflect the personality of the individual beneath
the skin. Our skin is unique to us
because it typically mirrors what
happens inside our body over the
course of our lifetime.
Estrogens
Our skin is one of the central organs known to benefit from higher
circulating levels of the estrogen
hormones (i.e., estriol, estradiol
and estrone). Receptors for the
estrogen hormones are located in
both the epidermal and dermal
skin layers, as well as in the blood
vessels of the skin. In women, the
highest number of estrogen receptors are found in the vagina.
The Skin and Hormones
Just as estrogens have beneficial
effects in maintaining bone density, high levels of circulating
estrogens improve fluid retention
and elasticity in our skin. They also
stimulate collagen production and
increase the moisture naturally
maintained by our skin. There is
a strong connection between the
amount of collagen in our skin and
skin thickness, thus skin thickness
may correlate with levels of the
estrogen hormones.
The skin is where much of the
body’s hormonal activity takes
place and, according to research
studies, the skin cannot function
without hormones. As a target
organ of numerous sex hormones
(such as the estrogens, progesterone and testosterone), the skin
contains different types of hormone receptors, including estrogen receptors, as well as receptors
for progesterone and testosterone.
The anti-stress hormone DHEA
and the sleep hormone melatonin
are also both found in human
skin and are converted to biological molecules with important
functions. DHEA is converted
into estrogen and other hormonerelated molecules found only in
the skin. Melatonin is synthesized
in the skin and, in low concentrations, is believed to stimulate cell
growth. Moreover, hormones
produced elsewhere in the body
are known to play a role in the
health of our skin.
With the growing volume of literature on estrogen hormones, it is not
surprising to find that some controversy still exists regarding the
effects of estrogens on the aging
of skin. In Nutrition for Women,
Dr. Ray Peat points out that when
treating the skin with supplemental estrogens, water and fat may accumulate in the skin, which is what
gives it the appearance of smoothing out wrinkles. He notes that
testosterone and progesterone may
offer more support by stimulating
production of collagen in the skin.
Testosterone
Our skin is also sensitive to the
action of testosterone. In fact,
one of the ways in which testosterone is excreted is through
glands within the layers of the
skin as sebum. Teenagers experiencing surges of testosterone
during puberty typically develop acne from blocked skin
pores that become clogged with
surplus sebum. Because testosterone levels naturally decline
as we grow older, an insufficient
amount of oil may be produced,
and this often causes the skin—
particularly on the face and
hands—to become noticeably
dry. Decreases in testosterone
may also result in thinning of
the skin as collagen production
declines.
Thyroid
Thyroid contributes to overall
skin health. In general, normal
levels of thyroid hormone are
associated with better hydrated
skin, as well as with thicker,
healthier looking skin. Now
that there are medical tools that
measure the circulation of blood
throughout our skin, we have
a better understanding of the
importance of thyroid hormone
in maintaining healthy skin.
Studies show that a low functioning thyroid may result in
reduced blood circulation. In advanced cases of hypothyroidism
(when the body produces too
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little thyroid hormone), the skin
may receive as little as 20 to 25
percent of the normal blood
supply. With reduced circulation, the nourishment supplied
by blood is compromised and
waste products are not removed
promptly and completely.
Hypothyroidism may result in
skin that becomes less resistant
to potential infection. Our skin
plays host to a wide range of
bacteria, some of which are quite
damaging if they are able to gain
access through the skin, invade,
and then multiply. When thyroid
function is compromised, so is
the skin’s ability to act as a barrier, and the body becomes more
prone to infections.
Reduced circulation of blood
through the skin is just one effect
of low thyroid function. Other
skin-related effects include an
unhealthy appearance due to
thinning, dryness and loss of
color. Yet another potential
symptom of low thyroid function is overproduction of a gellike substance in the skin called
mucin. Because mucin has a high
affinity for water, it can attract
and hold excess water, leading to
swelling all over the body.
Growth Hormone
Growth hormone also plays a role
in the health and vitality of skin.
In middle and late adulthood, we
all tend to experience a number
of changes in body composition,
including shrinking of lean body
mass, expansion of fat tissue, and
thinning of the skin. In a landmark
study published in 1990, Dr. Daniel Rudman and colleagues reported that adding back growth hormone could actually reverse the
effect of thinning skin. The results
of their study showed that skin
thickness increased more than 7%
among men who received human
growth hormone for six months,
whereas no significant changes in
skin thickness occurred in a group
receiving no treatment. This was
the first study to demonstrate that
a diminished growth hormone
level is responsible, at least in part,
for the thinning of skin that occurs
in old age.
Canvas for Hot Flashes
A discussion about skin and the
role of hormones is not complete
without a mention of hot flashes.
Hot flashes and their accompanying sensations of sweating are
acknowledged by many women
Possible Deficiency Skin-Related Symptoms
Estrogen Tiny vertical wrinkles around lips, dry skin, thin skin,
pale skin, little wrinkles around eyes, smile lines
Testosterone Lots of wrinkles, small wrinkles around eyes or mouth,
creased forehead, dry skin, thin skin, pale skin, sun
sensitivity, slow to heal
Thyroid Dry skin, pale skin, skin cancer
Melatonin Age spots, skin cancer
Growth Hormone Lots of wrinkles, large wrinkles on sides of nose and
mouth, small wrinkles around eyes or mouth, creased
forehead, dry skin, thin skin, slow healing
DHEA Age spots, dry skin
Some skin-related symptoms may be associated with a hormone deficiency.
(Adapted from The Hormone Solution by Dr. Thierry Hertoghe)
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and their clinicians as some of
the most common symptoms
of menopause. This is certainly
the case with Caucasian women,
although worldwide and within
different cultures there is considerable variation in the prevalence of these symptoms.
Triggers, Symptoms and
Frequency
Hot flashes may occur at any
time of the day and night, and
they are triggered by a variety of
actions as mundane as sleeping,
working, relaxing, drinking tea,
coffee or alcohol and eating spicy
food. The symptoms accompanying a trigger are also varied, but
the most common may include
a feeling of increasing pressure
in the head. During the night,
a decrease of rapid eye movement (REM) sleep and waking
often precede a hot flash. For
most women, hot flashes arise
as a sudden feeling of heat in
the face, neck or chest, and they
are often associated with patchy
flushing of the skin and profuse
perspiration. The initial focal
point may be very specific, such
as an ear lobe, the forehead or
the area between the breasts, but
a subsequent spread of the heat
sensation may continue upwards
and downwards throughout the
body. Heart palpitations also
frequently accompany a hot
flash. When these episodes occur
at night, a “domino effect” then
often leads to insomnia, irritability and general lethargy.
The frequency of hot flashes
varies among individuals, ranging from a few per month to several per hour; up to fifty per day
have been reported. Similarly,
the duration of a hot flash may
range from a few seconds up to
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one hour, although the average duration is usually around
three minutes. In most women,
hot flashes and their associated
symptoms may persist for over
a year, and approximately 25%
of women who experience hot
flashes report that they persist
for more than five years.
The Physiology of Hot Flashes
The physiologic changes that
accompany hot flashes include a
sudden increase of blood flow to
the skin, which then warms the
skin and provides the sensation
of a sudden rise in temperature.
A medical device that measures
body temperature changes
shows that during the course
of a hot flash, such alterations
occur over most parts of the
head, neck, trunk and limbs. Although the greatest temperature
changes are found in the fingers
and toes, hot flashes are usually
felt most strongly in the face,
neck and upper trunk. Research
indicates that the sensation
of heat is often out of proportion to the actual temperature
increase measured during hot
flashes. Furthermore, the temperature increase often persists
for several minutes after the
sensation of warmth has passed,
indicating that women experience a hot flash only while their
skin temperature is increasing.
The severity of the sensation
is therefore probably related
more to the rate of temperature
change than to the actual temperature increase.
Hot Flashes and Hormones
The clinical value of estrogen
therapy in helping to alleviate
hot flashes is well established,
although the exact mechanism
by which this occurs is not yet
understood. In some studies,
women with severe hot flashes
had significantly lower mean
body weight and levels of total
estrogen and estradiol than
women without hot flashes.
These findings suggest that
body size and its effects on the
metabolism of naturally occurring estrogens may be a factor in
the occurrence of hot flashes in
postmenopausal women.
Hormones, specifically estrogens, are a primary cause
of cellulite, and this explains
why men, who have much less
estrogen than women, never
get cellulite. Secondary to hormones in the formation of cellulite is genetics. As many of us
have learned, cellulite tends to
be hereditary, so if your mother
had cellulite, you are more
likely to have it as well.
Women with hot flashes also
tend to have more extreme
changes in their cycle of estradiol production, suggesting that
the rate of change in estrogen
levels could be a trigger for hot
flashes. This also suggests that
each individual may have a
specific range of estrogen levels
within which hot flashes will
occur, once they reach their
specific threshold. This variability among individual women
points to the value of trying
estrogen therapy and working
with a trained practitioner to
help determine the amounts
of estrogen hormones that are
most effective in alleviating hot
flashes and other uncomfortable
symptoms of menopause.
Due to hormones and genetics,
blood vessels in the skin tend
to weaken and further contribute to the formation of cellulite.
The weakening of blood vessels
explains why many women
tend to develop spider veins
and bruise very easily, especially on their thighs. Cellulite becomes visible when areas of the
skin become so weakened that
they break down and allow
fat cells below the skin layers
to push their way through the
skin and to the surface. The
best way to get rid of cellulite
and related stretch marks is to
work on repairing the damaged
dermis, rather than concentrating on burning fat.
Supplemental progesterone
has also been effective in treating hot flashes. A study by Dr.
Helene Leonetti established that
progesterone cream applied to
the skin of menopausal women
helped alleviate hot flashes and
excessive sweating. As in the
case of estrogens, the mechanism by which progesterone
controls hot flashes is not well
understood.
Cellulite
A discussion about skin and
hormones may also raise some
questions about cellulite.
Detoxification Pathway
While we mainly think of the
skin as a gateway for elements
ranging from sunlight, to moisturizing lotions, to hormones, it
is important to remember that
the skin has another critical
function: that of detoxification. When too many toxins
overwhelm the liver, intestinal
tract, and kidneys, the skin is
called into action. This is most
apparent when toxins exiting
the skin combine with surface
bacteria, resulting in blemishes
and acne. While acne is most
frequently seen in adolescence,
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many women develop acne
during midlife transition
when, as in adolescence, the
liver can be overwhelmed by
sudden bursts of estrogens.
where on the body a hormone
is applied. The sites of greatest hormone absorption are
the head, neck, scrotum and
armpits.
In The Ageless Woman, Dr.
Serafino Corsello cautions that
“if the liver is not adequately
supported by appropriate nutrients, the skin may wear the
brand of toxicity.”
It is also important to know
that other factors affect the
skin’s ability to absorb medications and hormones. One
study looked at estradiol absorption when applied as a gel
to three different-sized areas
of the skin in postmenopausal
women. The results indicated
that absorption was greatest
when applied to the smallest
area of skin. Moreover, absorption through the skin was
affected by washing the application site. Estradiol absorption was significantly reduced
at the two smallest application
sites when they were washed
30 minutes after the gel was
applied. Thus, when applying
hormone treatment to the skin,
it may be more effective to
apply a concentrated amount
to a smaller patch of skin and
then wait before washing the
area.
Hormone Absorption
Another important relationship between skin and hormones involves the application
of hormones directly to the
skin as a method of hormone
treatment. Sex hormones are
well-suited for absorption
through the skin. Studies demonstrate that, when applied
to the skin, the sex hormone
molecules can move through
the various layers and then
circulate in the blood to other
organs of the body.
A variety of factors affect the
skin’s ability to absorb hormones, including skin thickness, hydration (dry versus
oily), the size of the application area, where on the body
the hormone is applied, the
length of exposure, and the
type of formulation (such as a
cream, gel or patch).
Because everyone’s skin is
different, absorption will vary.
For example, skin thickness,
fat cell content, and skin cell
dimensions are different from
individual to individual, and
this even varies at different
locations on the same person.
In general, hormone absorption varies from one person
to another and is affected by
Hormone Changes and
Hormone Therapy
The critical roles that hormones play in maintaining
skin health may help explain
why hormone changes that
accompany aging and menopause have such a deep impact
on our skin. These changes
involve not only the way in
which our skin functions, but
its appearance too.
Hormonal changes affect collagen and elastin production, the
function of nerve endings, the
flow of blood within vessels,
and the secretions of glands.
As we age and our hormone
levels change, the skin tends
to become more acidic. Fluctuations in skin secretions
may alter the smell of our
skin, and changes in hydration, texture, and the relative
percentages of collagen and
elastin content certainly can
affect the look and feel of
our skin over time.
Dr. Mark Brincat was one of
the first to quantify the decrease in skin collagen after
menopause. He found that
the decrease in collagen and
subsequent decline in skin
thickness is what causes a
thin and somewhat translucent appearance. However,
this may be reversed with
adequate estrogen therapy.
Aging results in decreased
estrogen activity, and enzymes that convert DHEA
to estrogen also decline.
Women who take estrogens tend to have thicker,
healthier skin, and women
who take both estrogens and
testosterone tend to have
skin that is significantly
thicker (and healthier) than
women who don’t take
either hormone.
Hormone therapy may slow
the impacts of aging and
menopause on the skin’s
appearance, in ways that
are both direct and indirect.
Direct effects include improvements in skin collagen
and elastin activity, and
increased sweat and sebaceous secretions. Indirectly,
hormone therapy leads to
improvements in blood
vessel, nerve and immune
system functions.
Continued on Page 6
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Lawrence Galton; Harper & Row;
New York, NY; 1976.
The health of our skin is intimately entwined with our hormones. Therefore,
clinicians who specialize in treating and
caring for skin may be able to detect particular hormone deficiencies based upon
the appearance of the skin and certain
symptoms.
n“Effects of Human Growth Hormone
in Men Over 60 Years Old” by Daniel
Rudman, MD, et al; NEJM, July 1990.
n“Transdermal progesterone cream
for vasomotor symptoms and postmenopausal bone loss” by Helene
B. Leonetti, MD et al; Obstet Gynecol,
August 1999.
References
nThe UV Advantage by Michael F.
Holick, PhD, MD, and Mark Jenkins;
Simon Schuster; New York, NY; 2003.
nThe Cellulite Solution by Howard
Murad, MD; St. Martin’s Press;
New York, NY; 2005.
nHormone Replacement Therapy and the
Skin, Ed. Mark P. Brincat, PhD; Parthenon Publishing Group; New York,
NY; 2001.
nThe Ageless Woman by Serafina Corsello, MD; Corsello Communications,
Inc; New York, NY; 1999.
nNutrition for Women by Raymond Peat,
PhD, self-published; Eugene, OR;
1993.
n“Steady-state pharmacokinetics of
oestradiol gel in postmenopausal
women: effects of application area
and washing” by A. Jarvinen, et al;
Br J Obstet Gynaecol, 1997.
nThe Testosterone Revolution by Malcolm
Carruthers, MD; Thorsons; London;
2001.
nThe Hormone Solution by Thierry
Hertoghe, MD; Harmony Books;
New York, NY; 2002.
nHypothyroidism: The Unsuspected Illness by Broda O. Barnes, MD and
Connections is a publication of Women’s International Pharmacy, which is dedicated to the education and management of PMS, menopause, infertility, postpartum depression, and other hormonerelated conditions and therapies.
This publication is distributed with the understanding that it does not constitute medical advice for individual
problems. Although material is intended to be accurate, proper medical advice should be sought from a competent healthcare professional.
Publisher: Constance Kindschi Hegerfeld, Executive VP, Women’s International Pharmacy
Co-Editors: Michelle Davenport and Carol Petersen, RPh, CNP; Women’s International Pharmacy
Writers: Nicole Resnick, PhD, and Kathleen McCormick, McCormick Communications, Inc.
Illustrator: Amelia Janes, Midwest Educational Graphics
Copyright © October 2005, Women’s International Pharmacy. This newsletter may not be reproduced or
distributed without the permission of Women’s International Pharmacy.
For more information, please visit www.womensinternational.com or call (800) 279-5708.
Women’s International Pharmacy | PO Box 6468 | Madison, WI 53716-0468
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