Estrogen Your Antiviral Friend

Women’s Health:  Estrogen, Your Antiviral Friend

Good news, ladies - the female sex hormone estrogen has been found to have anti-viral effects against the influenza A virus, commonly known as the flu, according to a new study in American Journal of Physiology.

Estrogen is actually an important group of compounds that affect the growth and function of tissues throughout the body. Some occur naturally, some synthetically.

These estrogens have wide-ranging effects throughout life and in both sexes. Most animals depend on the hormones to regulate female development, reproduction, and sexual characteristics. Estrogen also affects blood fat levels, enzyme production, water and salt balance, bone density and strength, skin and blood vessel elasticity, heart muscle, and brain functions such as memory and sexual and even maternal instincts.

Flu Fighters

A virus infects and causes illness by entering a cell and making copies of itself inside the host cell. When it leaves the infected cells, the virus can spread through the body and between people. How much a virus has replicated determines its severity of its impact. Less replication of the virus means the infected person may experience less disease or is less likely to spread the disease to someone else, says Sabra Klein, PhD, of Johns Hopkins University and lead investigator of the study.

To examine how estrogen affected the flu virus's ability to replicate, the research team collected nasal cells -- the cell type that the flu virus primarily infects -- from male and female donors. The researchers exposed the cell cultures to the virus, estrogen, the environmental estrogen bisphenol-A and selective estrogen receptor modulators (SERM), which are compounds that act like estrogen that are used for hormone therapy.

The researchers found that estrogen reduced flu virus replication in nasal cells from women but not men. “Other studies have shown that estrogens have antiviral properties against HIV, Ebola and hepatitis viruses. What makes our study unique is two-fold. First, we conducted our study using primary cells directly isolated from patients, allowing us to directly identify the sex-specific effect of estrogens. Second, this is the first study to identify the estrogen receptor responsible for the antiviral effects of estrogens, bringing us closer to understanding the mechanisms mediating this conserved antiviral effect of estrogens", said Klein.

The findings in this new study support previous evidence from studies in animals that showed protective effects of estrogen against the flu. "Because estrogen levels cycle in premenopausal women, it may be difficult to see this protective effect in the general population," Klein notes. "But, premenopausal women on certain kinds of birth control or post-menopausal women on hormone replacement may be better protected during seasonal influenza epidemics," she says. "We see clinical potential in the finding that therapeutic estrogens that are used for treating infertility and menopause may also protect against the flu."

Too much of a good thing

You can get too much estrogen. Like most things in life, balance is important. If you are experiencing symptoms that indicate that your hormone levels are imbalanced, or symptoms that interfere with your well-being, visit your doctor. Remember that hormonal changes are quite common, particularly in women going through menopause.

However, if you are not within the normal age range for menopause or perimenopause or if your symptoms are intense, you may want to visit the doctor. Symptoms may include:

·         Hot flashes or trouble sleeping

·         Changes in mood or moodiness

·         Changes in sexual function or decreased fertility

Estrogens are more plentiful and play a larger role in women than men. In women, estrogen levels vary through life, surging at adolescence, wavering monthly in the reproductive years, and waning to low levels during menopause. Although indispensable, too much estrogen may cause some health issues.

There are many conditions that can cause symptoms such as hot flashes, loss of libido, and other symptoms associated with low estrogen levels. Do not assume that estrogen levels are the cause of your symptoms. Consult with your doctor before starting any treatment to increase your estrogen, including taking natural or herbal supplements.

Menopause comes with its share of unpleasant side effects, which may include memory loss, hot flashes, cramps and night sweats. There are a number of ways to approach the problem. Some will choose a natural solution.


A wonderful natural formula to help you live a longer, healthier life is Women’s Natural Balance (click here to view), a safe, and effective daily supplement that contains many of the top ingredients. This specially blended formula contains many safe azsand all natural substances that include black cohosh, soy isoflavones, red clover, Mexican yams and red raspberry extract.

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