In Traditional Chinese Medicine, the herbal remedy he shou wu (sometimes known as fo ti) is prescribed to enhance general health and increase life span, but its claim to fame is that it also is said to return gray hair to its original color. The direct English translation of he shou wu is "Black-haired Mr. He." In Chinese medicine theory, the kidneys control the growth and color of hair, and he shou wu is said to benefit the liver and kidneys. A commercial product called Fo Ti does not contain he shou wu but is often confused with it because of the similarity in names. Fo Ti can have severe side effects that sometimes have been attributed wrongly to he shou wu due to this confusion. As with any single herbal remedy, though, he shou wu may have side effects of its own.
He shou wu is sometimes used as a stool softener. It contains the substance emodin, which is a laxative and also is thought to be a liver protective agent. If you take too much or are sensitive to this herb, you may get diarrhea. This effect is primarily connected with taking the unprocessed root form of he shou wu.
Some people who are sensitive to he shou wu may develop a skin rash. This is rare, but it is a recorded side effect that occurs when high doses of the herb are consumed.
Reports of numbness in the arms and legs have been connected with the use of he shou wu. This effect only occurs when 15 or more grams of he shou wu are consumed in a daily dose, far above those recommended in the professional literature.
He shou wu has a moderate estrogenic effect, meaning it mimics the effect of the hormone estrogen in women. Even though he shou wu does not elevate human estrogen levels, it contains substances that can stimulate the growth of cancers that are sensitive to estrogen-like substances, so women battling certain cancers should not take it.
Rare reports of liver problems such as jaundice, abnormal function and hepatitis have been connected with the use of he shou wu. In some of these cases, the patients were taking a modified version of he shou wu called Shen-Min. This product for hair loss contains he shou wu combined with other herbs.