What Is Horsetail Extract Good For?

A small pile of horsetail beside a cup of tea.
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Herbal remedies have been around for ages, and horsetail is no exception. Known by the botanical name Equisetum, horsetail is a prehistoric plant with distinctive hollow stems. It contains silicon -- a substance that plays a role in keeping bones strong -- according to the University of Maryland Medical Center. Horsetail contains a wide variety of other compounds that may offer benefits, according to data published in the journal "Phytotherapy Research" in January 2006. Well-designed human studies are needed, however.

Anti-microbial Activity

Researchers from the University of Nis in Serbia identified 25 compounds from the oils extracted from horsetail leaves and found various compounds promote anti-microbial activity. They tested the oils against several microbes, including salmonella, E. coli, Candida albicans, fungi and Staphylococcus aureus. A 1:10 ratio of diluted horsetail oil showed a broad spectrum of significantly strong anti-microbial activity against all tested strains of microbes, according to the study. The results were published in the January 2006 issue of the journal "Phytotherapy Research."

Antixodant Activity

Horsetail appears to offer antioxidant benefits, according to a study published in the "Journal of Medicinal Food" in April 2010. Antioxidants help protect your cells by neutralizing unstable atoms known as free radicals. The study found that water extracts of certain compounds found in horsetail -- n-butanol, methanol and ethyl acetate -- exhibit significant free-radical scavenging activity. Free radicals have one or more unpaired number of electrons and can cause damage when they steal electrons from healthy cells.

Potential Anti-anxiety Capability

Certain compounds found in horsetail may offer anti-anxiety benefits, according to a study published in the May 2011 issue of the "Indian Journal of Experimental Biology." In this animal study, researchers compared the effects of different compounds extracted from horsetail to the anti-anxiety drug diazepam. Researchers found that out of the compounds tested, the ethanolic extract offers anti-anxiety benefits comparable to diazepam, with a lower sedative effect, according to the study. These results are promising, but human studies are needed.

Safety Precautions

Horsetail is considered safe when used short-term, according to the University of Maryland Medical Center. There are precautions to keep in mind, however. Avoid horsetail if you are at risk of low potassium because horsetail may increase potassium excretion. Avoid horsetail if you have gout, diabetes or kidney or heart problems as well. Horsetail may interact with diuretics, alcohol, nicotine patches or gum and the drug lithium.