|
The claims
For a while now, an Internet email rumor has suggested that
underarm antiperspirants cause breast cancer. It also claims that:
- Underarm shaving allows cancer-causing substances in
antiperspirants to be absorbed through razor nicks. These substances
are said to keep lymph nodes under the arm from removing cancer-causing
toxins before they get to the breasts.
- Most breast cancers develop in the upper outer quadrant of
the breast because that area is closest to the lymph nodes exposed to
antiperspirants. (A quadrant is 1/4 of the breast, if you think of the
breast as a circle. The upper outer quadrant of the breast is the part
closest to the arm pit.)
- Men have a lower risk of breast cancer because they do not
shave their underarms, and their underarm hair keeps chemicals in
antiperspirants from being absorbed.
All of these claims are largely untrue.
Our answers to frequently asked questions
about antiperspirants
Do antiperspirants increase a person's risk
of developing breast cancer?
There is no good scientific evidence to support this claim.
There are no strong epidemiologic studies in the available medical
literature that link breast cancer risk and antiperspirant use.
In fact, a carefully-designed epidemiologic study of this
issue published in 2002 compared 813 women with breast cancer and 793
women without the disease. The researchers found no link between breast
cancer risk and antiperspirant use, deodorant use, or underarm shaving.
Another study published in 2003 looked at responses from
questionnaires sent out to women who had breast cancer. The researcher
reported that younger women who were diagnosed with breast cancer said
they used antiperspirant and started shaving their underarms earlier
and shaved more often than women who were diagnosed when they were
older. But the study design did not include a control group of women
without breast cancer and has been criticized by experts as not
relevant to the safety of these underarm hygiene practices.
Probably, in general, young women are more likely than older
women to shave their underarms and use antiperspirants, whether or not
they develop breast cancer later. For instance, most women born in the
1950s and 1960s may have started shaving earlier and using
antiperspirants more often than women born in the 1930s and 1940s. Or,
it is possible that many women shave and use antiperspirants less often
as they get older. These are more likely explanations of the
researcher's findings than the suggestion that these practices cause
cancer. Of special note, the study asked about underarm products that
the women were using at the time the questions were answered, not what
they used before they developed breast cancer.
Does using antiperspirant after shaving
allow chemicals to enter the body from the armpit and increase breast
cancer risk?
Razor nicks may increase the risk of skin infection. If the
underarm skin already has an infection, it is possible that some
antiperspirants could cause slight irritation. But it is unlikely that
this is a major source of carcinogens (cancer-causing substances) that
ever reach the breast cells.
Should I be concerned about parabens in
antiperspirants?
Studies have shown that parabens, which are used as
preservatives in many skin care products (like lotion, make-up, and
sunscreen) can be absorbed through the skin. In 2004, a small study
found traces of parabens in some samples of breast cancer tumors.
Parabens are also used as preservatives in some underarm products and
may have entered the breast through the underarms in these cases. This
is a possible concern because studies have shown that parabens have
weak estrogen-like properties. Estrogen is a female hormone known to
cause breast cells (both normal and cancerous) to grow and divide. And
some conditions that increase the body’s exposure to estrogen
(like not having children, late menopause, obesity, etc.) have been
linked to an increased risk of breast cancer.
But there are some important points to keep in mind about the
2004 findings:
- The researchers looked only for the presence of parabens in
breast cancer samples. The study did not show that parabens caused or
contributed to breast cancer development in these cases -- it only
showed that they were there. What this means is not yet clear.
- Although parabens have weak estrogen-like properties, the
estrogens that are made in the body are hundreds to many thousands of
times stronger. So, natural estrogens (or those taken as hormone
replacement) are much more likely to play a role in breast cancer
development.
- Parabens are widely used as preservatives in shampoo,
lotions, other cosmetics, and even foods. This study did not contain
any information to help find the source of the parabens found in breast
tissue.
So far, studies have not shown any direct link between
parabens and any health problems, including breast cancer. What has
been found is that there are many other compounds in the environment
that also mimic naturally produced estrogen.
The bottom line is that larger studies are needed to find out
what effect, if any, parabens might have on breast cancer risk.
Should I be concerned about aluminum in
antiperspirants?
Aluminum-based compounds are the active ingredients in
antiperspirants. They block the sweat glands to keep sweat from getting
to the skin's surface. Some research has suggested that these aluminum
compounds may be absorbed by the skin and cause changes in estrogen
receptors of breast cells. Because estrogen can promote the growth of
both cancer and non-cancer breast cells, some scientists have suggested
that using the aluminum-based compounds in antiperspirants may be a
risk factor for the development of breast cancer.
Studies have looked at aluminum content of breast tissue, and
aluminum absorption through the skin, but no clear link to breast
cancer has been made. Researchers continue to look at this possible
breast cancer risk factor and more studies are needed.
Is it true that antiperspirants keep a person from sweating
cancer-causing toxins out through their underarm lymph nodes and this
leads to a build-up of these toxins in breast tissue?
Lymph nodes help clear out bacteria,
viruses, and other possible threats to the body, but the lymph nodes do
not release waste through sweating. Sweat glands are not connected to
lymph nodes. Sweat glands are located in the skin, not in the lymph
nodes. Most cancer-causing substances are removed by the kidneys (and
released into urine) and by the liver (and released into bile, which
mixes with and is eliminated with feces).
Are there lymph nodes in the upper outer
quadrant where most breast tumors occur?
Lymph nodes can be found throughout the breasts and have an
important role. The underarm (axillary) nodes filter most of the lymph
flowing out of the breast before it goes back into the body's
bloodstream. These nodes are under the arm, in the upper outer quadrant
of the breast, and near the collarbone.
The breast quadrants are not actually all the same size. About
half of all breast cancers develop in the upper outer part of the
breast, probably because most breast tissue is located in this area.
The number of breast cancers in the upper outer part of the breast is
in proportion to the amount of breast tissue in that area.
There is no evidence to suggest that the location of cancers
within the breast is related to using antiperspirants or underarm
shaving.
Are men less likely to get breast cancer
because antiperspirant gets caught in their underarm hair and is not
absorbed by their skin?
Men are much less likely than women to develop breast cancer,
mostly because men have much less breast tissue than women. Women have
about 100 times more breast tissue than men do and are about 100 times
more likely to develop breast cancer.
Hormones also play a role. Men with metabolic or genetic
conditions that lead to increased estrogen (female hormone) levels have
an increased risk of developing breast cancer.
Underarm hair and antiperspirant absorption have not been
linked to male breast cancer risk.
Why does my doctor tell me not to use
antiperspirant or deodorant on the day of my mammogram?
You are asked to not use antiperspirant or deodorant on the
day you get a mammogram because many of these products contain
aluminum. This metal can show up on a mammogram as tiny specks. These
specks can look like microcalcifications, which are one of the things
doctors look for as a possible sign of cancer. Not using these products
helps prevent any confusion when the mammogram films are reviewed.
How did the rumor about antiperspirants get
started and spread?
We don't know who started this rumor. Most people who
forwarded the e-mail did so with good intentions. We do know that this
rumor has been posted on some Web sites that sell deodorants that are
not antiperspirants, so these people might benefit financially from
spread of this misinformation.
How can I learn more about breast cancer
risk factors and ways to find breast cancer early, when treatment works
best?
Women concerned about breast cancer should know that their
risk of breast cancer is much more likely to be affected by factors
known to affect hormone levels in the body, such as obesity and hormone
replacement therapy after menopause. Women who want to reduce their
risk of developing or dying from breast cancer should avoid hormone
replacement therapy, stay at a healthy weight, exercise regularly,
limit the amount of alcohol they drink, and get regular mammograms.
For more information, talk to your doctor, nurse, or other
healthcare providers. You can also contact your American Cancer Society
at 1-800-227-2345 or visit our Web site, www.cancer.org. We
can give you information about all aspects of breast cancer, from
causes and prevention, to diagnosis and treatment.
Additional resources
More information from your American Cancer
Society
We have selected some related information that may also be
helpful to you. These materials may be ordered from our toll-free
number, 1-800-227-2345.
National organizations and Web sites*
In addition to the American Cancer Society, other sources of
information and support include:
National Cancer
Institute
Toll-free number: 1-800-4-CANCER (1-800-422-6237)
TYY: 1-800-332-8615
Web site: www.cancer.gov
For up-to-date cancer and coping information, clinical trials, and
other resources
National Women's
Health Information Center (NWHIC)
Toll-free number: 1-800-994-9662
TYY: 1-888-220-5446
Web site: www.womenshealth.gov
Offers information on many women's health issues, including cancer
References
Darbre PD. Aluminium, antiperspirants and breast cancer. J Inorg Biochem.
2005;99(9):1912–1919.
Darbre PD. Metalloestrogens: an emerging class of inorganic
xenoestrogens with potential to add to the oestrogenic burden of the
human breast. Journal
of Applied Toxicology. 2006;26(3):191–197.
Darbre PD, Aljarrah A, Miller WR, Coldham NG, Sauer MJ, Pope
GS. Concentrations of parabens in human breast tumours. Journal of Applied Toxicology.
2004;24(1):5–13.
Darbre PD, Harvey PW. Paraben esters: review of recent studies
of endocrine toxicity, absorption, esterase and human exposure, and
discussion of potential human health risks. J Appl Toxicol.
2008;28(5):561–578.
Exley C, Charles LM, Barr L, Martin C, Polwart A, Darbre PD.
Aluminium in human breast tissue. J
Inorg Biochem. 2007;101(9):1344–1346.
Final amended report on the safety assessment of
Methylparaben, Ethylparaben, Propylparaben, Isopropylparaben,
Butylparaben, Isobutylparaben, and Benzylparaben as used in cosmetic
products. Int J Toxicol.
2008;27 Suppl 4:1–82.
McGrath KG. An earlier age of breast cancer diagnosis related
to more frequent use of antiperspirants/deodorants and underarm
shaving. European
Journal of Cancer Prevention. 2003;12:479–485.
McGrath KG. Apocrine sweat gland obstruction by
antiperspirants allowing transdermal absorption of cutaneous generated
hormones and pheromones as a link to the observed incidence rates of
breast and prostate cancer in the 20th century. Med hypotheses.
2009;72(6):665–674.
Mirick DK, Davis S, Thomas, DB: Antiperspirant Use and the
Risk of Breast Cancer. Journal
of the National Cancer Institute.
2002;94:1578–1580.
Namer M, Luporsi E, Gligorov J, Lokiec F, Spielmann M. The use
of deodorants/antiperspirants does not constitute a risk factor for
breast cancer [article in French]. Bull
Cancer. 2008;95(9):871–880.
National Cancer Institute. Antiperspirants/Deodorants and
Breast Cancer: Questions and Answers. 2008. Accessed at:
www.cancer.gov/cancertopics/factsheet/Risk/AP-Deo on August 18, 2009.
Rados C. Antiperspirant Awareness: It’s Mostly No
Sweat. FDA Consumer Magazine. July-August 2005. Accessed at:
www.medicinenet.com/script/main/art.asp?articlekey=53207 on August 19,
2009.
Robb-Nicholson C. By the way, doctor. I recently received an
e-mail warning about a risk for breast cancer associated with using
antiperspirants. Are you familiar with this theory? Is it valid? Harvard Womens Health Watch.
2001;8(7):7.
Surendran A. Studies linking breast cancer to deodorants smell
rotten, experts say. Nature
Medicine. 2004;10:216.
Last Medical Review: 08/20/2009
Last Revised: 08/20/2009
|
