What are hot flashes?
A hot flash (also known as a hot flush) is a sudden feeling of heat, usually on your face, neck, shoulders, and chest. You may begin sweating profusely, and your heart might start pounding. These symptoms can last for only a few seconds or minutes, or they can go on for as long as half an hour. The overheated sensation is sometimes followed by a slight chill, and hot flashes that occur during the night are called night sweats.
For some women, hot flashes are little more than a nuisance, an occasional passing sensation of warmth. Others experience intense waves of heat that come on out of the blue, leaving them drenched in sweat several times a day and disturbing their sleep at night.
What causes them?
Researchers don't know exactly what causes hot flashes, but they're thought to be linked to a decrease in the body's production of estrogen -- something that usually happens as you approach menopause. In fact, hot flashes are the most common sign that menopause is on the way. About 75 percent of women have them, often beginning two or three years before they stop menstruating and in some cases even earlier. Some women are bothered for only a few months, but more commonly, hot flashes continue for three to five years.
You can also get hot flashes after giving birth (when your estrogen levels fall back to normal), after having your ovaries removed (since that's where your estrogen comes from), or during a time when you're on medications such as GnRH inhibitors or tamoxifen (because they're designed to reduce your estrogen levels). Finally, you may experience similar symptoms if your levels of thyroid hormone are out of whack.
What can I do?
Try to keep cool, both physically and emotionally. Dress in loose layers so you can quickly peel off some clothing if a hot flash should hit. Choose absorbent cotton clothes when you can; synthetic fabrics trap heat. Keep your home cool, a fan handy, and an ice-cold drink by your side. And cut down on stress; meditation, yoga, or massage can help. Avoid spicy foods and hot drinks if you find that they bring on hot flashes. It's also a good idea to cut back on caffeine, alcohol, and smoking and to get plenty of aerobic exercise, such as walking or swimming.
Can medications help?
If your hot flashes are frequent and interfere with sleep or daily life, your doctor may suggest hormone replacement therapy to supplement your declining estrogen. Because some evidence links hormone replacement therapy used for as little as five years with increased risk of strokes, blood clots, heart disease, and invasive breast cancer, you'll want to review your medical history thoroughly with your doctor to decide whether HRT is a good option for you. A high-blood pressure medication called clonidine is also helpful in some cases. And finally, some studies indicate that various antidepressants (like venlafaxine and paroxetine) can also reduce the frequency of hot flashes in some women.
What about alternative treatments?
Some women find that taking a vitamin E supplement brings relief (try 400 international units daily), but talk to your doctor first if you're on any blood-thinning medication. Others have discovered that acupuncture helps them keep their cool. Most so-called natural remedies come from plants and herbs containing phytoestrogens, compounds that are chemically similar to human estrogens.
Take soybeans, for example: It's long been known that Japanese women, who eat large quantities of soy foods, have fewer hot flashes than women in the West, though studies of the effect of soy on hot flashes have had mixed results. Since soy can benefit your body in other ways -- some studies show it may help keep your heart healthy, for instance -- adding soybean-based foods like tofu, tempeh, miso, soy milk, and roasted soy nuts to your diet is still a good idea.
Then there's black cohosh root, which has been approved for the treatment of hot flashes by Germany's Ministry of Health. In one study, 80 women who'd been averaging about five episodes per day were down to one a day after taking the herb for three months.
Dong quai is often promoted as a remedy for hot flashes and other menopausal symptoms, but a recent study found that it's no more effective than a dummy pill. (Chinese herbalists recommend that it be taken in combination with other herbs, as prescribed by a qualified practitioner.)
Sarah Henry is an award-winning health writer specializing in parenting and social issues. She was a staff writer for the Center for Investigative Reporting for more than a decade, and has also reported on health issues for Hippocrates, Time Inc. Health, the Washington Post, the Los Angeles Times Magazine, and for television programs such as "60 Minutes" and PBS's "Health Quarterly."
Preliminary progesterone research finds hot flash reduction, Menopause News, August 1, 1998 (on double-blinded, placebo-controlled study by gynecologist Helene Leonetti at St. Luke's in Bethlehem) Five Herbs That Ease Menopause, Varro Tyler, Prevention, March 1, 1999 Menopause: Herbs that can ease the transition, Herbs for Health magazine (black cohosh, vitex, dong quai,) Breathe Away Hot Flashes, Carol Krucoff, BodyWorks, 1998 (on studies by Wayne State behavioral nerosciences professor Robert Freedman re: using deep breathing to relieve hot flashes; using regular aerobic exercise to cool flashes) Interview with Adam J. Duhl, Department of Obstetrics and Gynecology, John Hopkins Medical Institutions, InteliHealth.
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Reviewed by Linda Tsai, M.D., a staff attending physician at Rochester General Hospital (affiliated with the University of Rochester School of Medicine) in Rochester, New York.