Holistic Health Herbal Medicine The Health Benefits of Horsetail For Treating Osteoporosis and Promoting Hair Growth By Sherry Christiansen Sherry Christiansen is a medical writer with a healthcare background. She has worked in the hospital setting and collaborated on Alzheimer's research. Learn about our editorial process Sherry Christiansen Medically reviewed by Medically reviewed by Arno Kroner, DAOM, LAc on July 09, 2020 facebook twitter linkedin Arno Kroner, DAOM, LAc, is a board-certified acupuncturist, as well as an herbalist and integrative medicine doctor. He operates a private practice in Santa Monica, California. Learn about our Medical Review Board Arno Kroner, DAOM, LAc Updated on October 10, 2020 Print Verywell / Anastasia Tretiak Table of Contents View All Table of Contents Health Benefits Possible Side Effects Selection, Preparation, & Storage Other Questions Horsetail (Equisetum arvense) is an herb in the Equisetaceae family of plants, which have been used since ancient Greek and Roman times. Traditionally horsetail has been used as a medicinal herb to treat osteoporosis, tuberculosis, and kidney problems. Horsetail was also used as a diuretic (for relief of fluid retention) and to stop bleeding and heal wounds. However, there are very few reliable research studies available to solidify the claims that horsetail is safe or effective for use as a medicinal herb. The perennial plant, sometimes considered a weed, spreads quickly and can rapidly invade a garden, or other moist habits. The fern-like horsetail plant, with hollow, pointed stems and scaly leaves, grows to about 12 inches tall. Only the green fern-like part of the plant is used for medicinal purposes; the root is not used. Also Known As AsprêleBottle brushCoda cavallinaCola de caballoCommon horsetailEquisetumField horsetailHorse herbHorsetail grass Horsetail rushHorse willowQueue-de-RenardScouring rush Shave grassSpring horsetail 5 of the Most Popular Alternative Medicines Used Today Health Benefits Although there is not enough clinical research data to back the claims of the touted health benefits of horsetail, the plant has been used to treat many conditions, including: BleedingGoutFrostbiteHeavy menstrual periodsIncontinence (inability to control the bladder)Kidney or bladder stonesOsteoarthritisUrinary tract infectionsWeight lossWounds Studies Osteoporosis involves softening/thinning of the bone tissue; this often occurs in menopausal women. Horsetail contains silicon, a mineral needed for healthy bone and connective tissue production. This is the reason that horsetail has been used to treat osteoporosis in menopausal women. A 2016 animal study published in the Indian Journal of Pharmacology found calcium, vitamin D, zinc -lysine, L-proline, L-arginine, and L-ascorbic acid (N) accelerate the mineralization of bone matrix and bone formation and adding a horsetail extract was beneficial for bone formation. More research studies (particularly studies involving humans) are needed to prove the efficacy of horsetail in the treatment of osteoporosis. Huntington College of Health Sciences reports that horsetail is an excellent source of the amino acid cysteine, along with minerals such as selenium, which are known to enhance hair growth. In an animal study published by the Pakistan Journal of Biological Sciences, the study authors explain that horsetail may have a significant antidiabetic effect stating that more studies are needed to identify exactly how Equisetum arvense (horsetail) works to lower blood sugar. How Does it Work? The chemicals in horsetail are thought to have anti-inflammatory (reducing inflammation) and antioxidant (chemicals that help boost the immune system) properties. Horsetail contains silica and silicon, minerals that work together to strengthen the hair and nails, as well as promoting healthy bone tissue. Selenium is also found in horsetail; this is a mineral, known to help the hair grow. An Overview of Holistic Health Possible Side Effects Horsetail is listed by the FDA (Food and Drug Administration) as being an herb of undefined safety according to DailyMed. Special Warning Horsetail may be unsafe when taken long-term because of an enzyme contained in the herb, called thiaminase. This enzyme breaks down thiamine (vitamin B1), rendering it useless. An abundance of could result in thiamine deficiency. Although there are some commercial horsetail products that are labeled free of thiaminase, it’s important to keep in mind that herbal supplements are not regulated by the FDA and labeling can be deceptive. In addition, there is not enough reliable medical research evidence to know whether thiaminase-free products are safe. Contraindications Contraindications are situations (including treatments, other drugs, or illnesses) in which a specific medication or herbal supplement should not be used. Horsetail is contraindicated for those who have these conditions: Alcohol use disorders: Horsetail decreases the body's ability to use thiamine and excessive alcohol intake increases the risk of thiamine deficiencyPregnancy or breastfeeding: There is not enough clinical research evidence to prove the safety of the use of horsetail during pregnancy or breastfeeding.Diabetes: Horsetail is thought to lower blood sugar and can result in dangerously low blood sugar levels in diabeticsThiamine deficiency: Horsetail breaks thiamine in half, rendering it ineffective in the body, which can lead to thiamine deficiencyHypokalemia (low potassium level): Horsetail’s diuretic (fluid flushing) effect may remove too much potassium from the body as it flushes fluids, leading to worsening of low potassium levels Drug Interactions Horsetail should not be taken with: Lithium: The diuretic effect of horsetail may interfere with the rate at which lithium is excreted from the body, this could result in a change in lithium levels (potentially causing serious side effects).Diabetic drugs such as Amaryl (glimepiride), glyburide, insulin, pioglitazone, rosiglitazone, Diabinese (chlorpropamide), Glucotrol (glipizide), Orinase (tolbutamide), and more. Because horsetail has been found to lower blood sugar taking the herbal supplement with insulin, or other diabetic drugs could result in dangerously low blood sugar levels.Diuretics (water pills), particularly those that decrease potassium, such as Diuril (chlorothiazide), Thalitone (chlorthalidone), Lasix (furosemide) and hydrochlorothiazide (HCTZ). A small randomized double blind study found that horsetail was as effective as for its diuretic effects.Nicotine patches or nicotine gum: Horsetail also contains nicotine, therefore it should not be taken when chewing the gum or using nicotine replacement patches.Lanoxin (digoxin): Those with heart irregularities (arrhythmias), as well as people taking digoxin, should not take horsetail, due to the herb's ability to lower potassium levels (which may impact how regularly the heart beats and worsen cardiac arrhythmias). Before taking any type of herbal supplement, you should first consult with the professional health care provider, particularly if you take prescription medications. Over-the-counter drugs, natural supplements, and vitamins can also interact with herbal supplements such as horsetail. Always use caution and follow the health care providers recommendation on the use of horsetail and all other medicinal herbs. Verywell / Anastasia Tretiak Selection, Preparation, & Storage Medicinal preparations made with horsetail from Equisetum are usually considered safe, however, another species of horsetail, named Equisetum palustre was found to be poisonous to horses. Preparation Horsetail is available as a dried herb to use in tea and other mixtures as well as a liquid form. Capsules and tinctures are also available. Just as with all other herbal supplements and drugs, the dose of horsetail depends on many factors, including a person’s age, health status, and more. These factors have not been studied enough to come up with a safe and effective dose when taking horsetail. Be sure to follow the instructions of the naturopath, pharmacist, physician or other health care professional, and always read and follow the package insert/label regarding dosage. Regardless of the reports of toxicity surrounding horsetail, some herbal experts still recommend its use. For example, James A Duke, Phd. The average dose of horsetail depends on the condition that is being treated, average doses may include: Brittle nails: A specific type of topical formulation (including horsetail and other chemical elements) applied every night for 29 days (or every other day for 14 days) in clinical trials.Diuretic: A dry extract of horsetail containing 0.026% total flavonoids was given as a 300 mg dose, by mouth three times per day.Wound healing: A 3% horsetail ointment was applied to the episiotomy site in postpartum mothers every 12 hours for 10 days. Penn State Hershey dosages of horsetail include: A capsule: The standard dose has 10% to 15% silicaAn herbal infusion: 2 to 3 teaspoons of dried horsetail, three times per dayA tincture: Ratio should be 1-to-5 (dosage should be determined by a health care provider)A compress (for wounds or skin treatment): 10 grams of herb per 1 liter (33.8 ounces) of water per day Storage All preparations should be kept in a sealed dark container and protected from exposure to light. 10 Most Common Herb Mistakes and How to Avoid Them Other Questions Is it safe to eat horsetail? There are two spring harvest offerings from the horsetail plant; these include the fertile tan-colored shoots that appear in the early season—these are edible. The young, tan-colored shoots were traditionally eaten by Native Americans and the Japanese, but the safety of ingesting the plant has not been proven. The green stalks that appear later can be used for medicinal purposes, but they are not edible. Can horsetail promote hair growth for everyone? Horsetail has not been proven to grow hair, but the herb is thought to replenish the minerals in the diet (such as selenium) which are known to promote healthy hair growth. However, the use of nutritional supplements is not known to be effective for everyone, in fact, there is limited research available on dietary supplementation and loss of hair. Despite the lack of research data, many hair loss products have “active ingredients’’ that include selenium. It’s important to note that selenium toxicity is well documented and one side-effect of taking too much selenium is hair loss. Is horsetail safe for children to take? No. Horsetail has traces of nicotine and is not recommended for kids. Where does it name come from? The word "Equisetum" comes from the Latin words “equus” meaning horse and “seta” meaning bristle. This name was derived from the bristle-like properties of the leaves of the horsetail plant, thus its common name, “bottle brush.” Do note that it is a different plant from Callistemon, which has bristly red flowers that look like a bottle brush. A Word From Verywell Horsetail is an herb that may have some beneficial medicinal properties, but it should be used with caution. Not only are there concerns about the safety and effectiveness of horsetail, taking the herb by mouth may deplete the body’s level of thiamine (B1). Those who do take horsetail daily should take a quality B complex or multivitamin daily. As with all other herbal supplements, only use horsetail under the supervision of your health care provider. Was this page helpful? Thanks for your feedback! Sign up for our Health Tip of the Day newsletter, and receive daily tips that will help you live your healthiest life. Sign Up You're in! Thank you, {{form.email}}, for signing up. There was an error. Please try again. What are your concerns? Other Inaccurate Hard to Understand Submit Article Sources Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy. Alasadi, TA. What is the role of silicon in human and disease? Professor of Chemistry. Wasit University. Updated January 1, 2016. Bruno, G. Have a Good Hair Day. Huntington College of Health Sciences. Updated 2009. Safiyeh S, Fathallah FB, Vahid N, Hossine N, Habib SS. Antidiabetic effect of Equisetum arvense L. (Equisetaceae) in streptozotocin-induced diabetes in male rats. Pak J Biol Sci. 2007 May 15;10(10):1661-6. U.S. National Library of Medicine: Daily Med. EQUISETUM ARVENSE- equisetum arvense top pellet. Updated April 1, 2016. Carneiro DM, Freire RC, Honório TC, et al. Randomized, Double-Blind Clinical Trial to Assess the Acute Diuretic Effect of Equisetum arvense (Field Horsetail) in Healthy Volunteers. Evid Based Complement Alternat Med. 2014;2014: doi:10.1155/2014/760683 James A. Duke, Ph.D. The Green Pharmacy Handbook. Emmaus, PA: Rodale Press, 1997:80. Penn State Hershey. Milton S. Hershey Medical Center. Health Information Library. Horsetail. Updated January 2, 2015. Additional Reading Sripanyakorn S, Jugdaohsingh R, Dissayabutr W, Anderson SH, Thompson RP, Powell JJ. The comparative absorption of silicon from different foods and food supplements. Br J Nutr. 2009;102(6):825–834. doi:10.1017/S0007114509311757 Swati D. Kotwal and Smita R. Badole, S.R.., Kotwal, S.D. Anabolic therapy with Equisetum arvense along with bone mineralising nutrients in ovariectomized rat model of osteoporosis. Indian Journal of Pharmacology; 2016; 48 (3): 312–315. doi:10.4103/0253-7613.182880. U.S. National Library of Medicine: Daily Med. EQUISETUM ARVENSE- equisetum arvense top pellet. Updated April 1, 2016.