Uses of horsetail for hair include increasing hair strength and sheen, discouraging hair loss, and restoring moisture to dry hair. Using horsetail for hair may help promote growth and may discourage brittleness. Horsetail typically grows in moist areas of North America and is otherwise known as Equisetum arvense. Silica is one of the active substances in horsetail, and it also contains manganese, potassium, and selenium.
Silica is known to strengthen the hair and also can help the hair maintain its shine. Minerals such as potassium, selenium, and manganese also can help promote hair growth and fullness. Horsetail for hair can be consumed as a tincture or tea, and it can also be applied topically to the hair. Supplements can be purchased at most nutrition stores, however, a health care provider should be consulted before taking them.
Taking horsetail orally can cause a decrease in the body's level of thiamine, a B vitamin. People who take horsetail for hair may want to consider taking a multivitamin on a daily basis to counteract a potential deficiency. In addition, taking horsetail for hair may deplete the body of potassium stores, and subsequently should not be taken by people who might be deficient in potassium.
It is recommended that people with conditions such as diabetes, gout, cardiac disorders, or kidney disorders avoid using horsetail for hair. Pregnant women, and those who are breastfeeding should also avoid taking horsetail. Also, horsetail may negatively interact with certain medications such as water pills and nicotine preparations. Similarly, people who drink chronically should not take horsetail because people who consume large amounts of alcohol are already prone to decreased vitamin B1 levels, and taking horsetail can exacerbate that deficiency.
People who take horsetail for hair should not expect to see immediate results, as it can take up to six weeks of using the product to see changes, such as a smoother texture and a increase in shine. Since horsetail is considered a dietary supplement and not a medication, there are no established dosage guidelines. Discussing horsetail for hair with an experienced herbalist, alternative medicine practitioner, or health care professional may be prudent before beginning therapy with horsetail. Side effects from consuming horsetail may include stomach upset, nausea, vomiting and diarrhea. In addition, drowsiness, headache, an increase or decrease in urinary output, and scalp irritation may occur.