Horny goat weed is a plant used in traditional Chinese medicine. As its nickname, "natural Viagra," implies, some people use horny goat weed to improve sexual function and arousal.

The health and sexual benefit claims for horny goat weed go back thousands of years.

As a form of alternative medicine, the herb has been used to treat conditions from hay fever, to atherosclerosis, nerve pain fatigue, osteoporosis, and erectile dysfunction.

There have been studies conducted on cells in laboratories that report evidence of several beneficial properties of horny goat weed. Early research suggests that it may have properties that can keep bones strong, protect the nerves, and support the immune system.

Other cell research has revealed the following possible effects:

anticancer effects
anti-HIV activity
radio sensitizing effects
reversal of multidrug resistance in some tumor cells
postmenopausal bone loss prevention
Atherosclerosis is a condition where the arteries in the neck harden. For people with atherosclerosis, a mixture containing horny goat weed may be beneficial and result in improved symptoms and clinical tests.
People with hay fever may experience symptom relief and a reduction in white blood cells that tend to increase with allergies.

Erectile Dysfunction
Horny goat weed contains a substance called icariin. Icariin can block a protein linked with erectile dysfunction called phosphodiesterase type 5 (PDE5).
PDE5 basically limits the increase in blood flow to the penis that is needed for an erection. Erectile dysfunction happens when there's not enough blood flowing to the penis.

Normally, the body curbs PDE5 levels. In people who have erectile dysfunction, PDE5 might not be controlled the way it should be.

According to folklore, a Chinese goat herder noticed that his flock had heightened sexual activity after eating the plant. This led to the discovery of the plant's aphrodisiac (sexually stimulating) qualities. So, if you were wondering where this herbal remedy got its name, now you know.

Alternative medicine practitioners propose that horny goat weed is useful in complementary therapy to treat certain conditions.

These include:
Erectile dysfunction
Low libido (sexual desire)
Osteoarthritis ("wear and tear" arthritis)
Osteoporosis (thinning of the bones)
Joint pain
Bronchitis (swollen airways to the lungs)
Heart disease
High blood pressure

Some claim that horny goat weed can improve circulation by thinning the blood. It has also been used to relieve symptoms of premenstrual syndrome (PMS), sharpen memory, and boost energy.

Few studies have looked at the benefits of horny goat weed. The main studies are in vitro (conducted in test tubes) or animal studies. Erectile dysfunction and bone disorders are the two most common conditions that have been studied.