What Are the Benefits of Horsetail Grass?

Horsetail grass is an herb you can drink as tea, take in powder or capsule form or consume as liquid extract for its health benefits. It's been used in traditional medicine mainly for removing stones from the excretory system and for improving bone health. Horsetail does have interactions with certain medications, so check with your doctor before taking it. According to the University of Maryland Medical Center, horsetail grass is not recommended if you're pregnant or breast-feeding.

Close-up of horsetail grass in a forest. (Image: anmbph/iStock/Getty Images)

It Promotes Bone Health

Horsetail contains silica, a mineral that helps in bone repair and building strong tendons and bones by encouraging calcium absorption. Traditionally, it's administered to help speed up bone healing after fracture or other bone trauma. It's also recommended to help treat osteoporosis. In a study published in "Cell Proliferation" in 2012, scientists looked at how horsetail extract would interact with human bone cells in test tubes. They found that horsetail induced bone cell growth and concluded it may have potential in human bone regeneration.

It's a Diuretic

According to an article published in the "Journal of Ethnopharmacology" in 2007, horsetail grass has naturally occurring diuretic properties. MedlinePlus reports it is used as a natural remedy for excess fluid retention, kidney stones, bladder stones and urinary tract infections. Its diuretic action is traditionally believed to speed up the excretion of kidney stones, but scientific evidence to validate its effectiveness is lacking.

It Lowers Blood Glucose Levels

A study published in the "Journal of Ethnopharmacology" in 2002 looked at the effects of horsetail extract on a small sample of patients with Type 2 diabetes. Some of the patients were given one dose of the extract orally, while others were given a placebo. Scientists measured the patients' glucose levels at the time of the administration and at different intervals afterward. They found that blood glucose levels were significantly reduced at 90 minutes, two hours and three hours after horsetail administration, as compared to the placebo. This research suggests horsetail could potentially play a role in managing glucose levels.

It's Better to Take It in Small Doses

Although horsetail has some health benefits, it's not considered safe for children, and it's not to be taken in large doses or regularly over a long period. Taking horsetail consistently in the long term could cause thiamine deficiency, and this risk is exacerbated if you drink alcohol regularly. The University of Maryland Medical Center recommends taking no more than 300 milligrams of horsetail grass three times daily. If you're making horsetail grass tea, brew no more than 3 teaspoons of it three times a day.