Horsetail Tea: What It's For, How to Make it & Side Effects

Clinical review: Manuel Reis
Registered Nurse

Horsetail is a medicinal plant from the Equisetum arvense species that is very commonly used as a home remedy to treat fluid retention, for weight loss, and to strengthen the bones. Due to its anti-inflammatory and diuretic effects, horsetail can also be used to help with treatment of kidney stones and urinary tract infections.

Horsetail tea prepared with a dry stem is the method most used to consume the plant. It can be found in natural health stores and in some compound pharmacies. Horsetail can also be found in capsule form.

Although it has several diverse health benefits, horsetail use can also cause side effects, especially if it is used in high doses or for over a week. It can cause a strong headache or pancreatitis, for example. Therefore, use should always be guided by a doctor or a health professional with experience in medicinal plants.

What it is used for

Horsetail contains diuretic, anti-inflammatory, antioxidant, antimicrobial, healing and re-mineralizing properties. Therefore it can be used to achieve many health benefits.

The main used of horsetail are:

1. Treat fluid retention

Horsetail possess diuretic effects due to its high amounts of flavonoids, like quercetin e apigenin, phenolic compounds and mineral salts, all which help to increase the production and elimination of fluid through the urine. This treats swelling and fluid retention.

One study shows that taking one daily dose of 900mg of horsetail in capsule form has a diuretic effect that is actually more potent than a pharmaceutic diuretic, like hydrochlorothiazide. Nonetheless, more studies are needed to support this effect.

2. Help with weight loss

Horsetail helps with weight loss due to its composition of antioxidants, anti-inflammatories, detox substances and diuretics, like flavonoids and caffeic acid. These substances help  to burn localized fat and help with the elimination of fluids that can cause weight gain.

In addition, caffeic acid found in horsetail has a thermogenic effect, which helps to boost metabolism and burn fat, ultimately leading to weight loss.

3. Treat urinary infections

Due to its diuretic effect, horsetail can be useful for treating urinary infections and other renal or urinary problems, like cystitis or nephritis. This is because by stimulating the elimination of urine, this plan will also promote the elimination of bacteria that are causing these illnesses through the urinary tract.

4. Decrease blood pressure

Horsetail helps to decrease blood pressure due to its diuretic effect, which increases the elimination of fluid from the body. This results in a reduction is fluid in the blood vessels, which also decreases the force at which the heart has to against to pump blood, decreasing blood pressure.

5. Maintain bone health

Horetail is rich in minerals like calcium, phosphorus, and magnesium, which are minerals that are fundamental for strengthening the bones and maintaining their health.

In addition, some lab studies show that horsetail can prevent the breakdown of bones and actually stimulate their growth and regeneration. This prevents the development of illnesses like osteoporosis, osteopenia and Ricketts, for example. 

Other studies show that due to its high levels of silica, horsetail can also improve the formation, density and consistency of bones and cartilage, as well as increase the synthesis of collagen and improve the absorption of calcium in the bones.

Nonetheless, more studies are needed to support these benefits.

6. Improve the appearance of skin and fingernails

The silica present in horsetail can reduce fragility and the appearance of waves in the fingernails. It also increases the hydration and strengthens fingernails, which helps to improve their overall appearance.

In addition, horsetail also as astringent, anti-inflammatory and antioxidant properties, which contribute to the improvement of skin quality. It fights off free radicals that cause cellular damage and cause early aging, and also helps to reduce oil in the skin and prevent the appearance of acne.

7. Eliminate fungi and bacteria

Some studies show that horsetail contains essential oils like thymol and cineole, which are able to eliminate fungi (especially skin fungus, like Candida sp.) and bacteria like:

  • Escherichia coli which causes urinary infections, and
  • Staphylococcus aureus which causes lung, skin and bone infections.

More studies are necessary to support this benefit, however.

How to make horsetail tea

Horsetail tea is the main way to consume this plant. It is made with a dry stem, and can be used as a diuretic to complement the treatment of urinary infections, to lose weight, or to treat high blood pressure.

Ingredients

  • 1 tablespoon of dried horsetail stem 
  • 1 cup of boiling water

How to prepare

Place the dried stem in the boiling water and allow it to soak for 5 to 10 minutes. Strain the infusion and drink up to 2 cups per day, ideally after the first meals of the day.

This tea should not be used for more than 1 week in a row to prevent dehydration and the elimination of essential minerals in the body.

Other ways to use horsetail

In addition to tea, horsetail can also be found in 100mg capsules. They can be taken after breakfast and lunch,  but they should only be taken under medical supervision or with guidance from a health care professional with experience in medicinal plants.

Another way to use horsetail is to use it in a sitz bath for the treatment of urinary infections. To make a sitz bath, place 3 handfuls of dried horsetail stems in bathwater and sit in the water for 5 to 10 minutes. Learn about other home remedies and sitz baths you can try to treat vaginal infections.

Possible side effects

Horsetail is safe for use in the majority of adults when it is consumed for short periods of time (up to one week), or if it is consumed as directed by a doctor, registered dietitian or medicinal plant specialist.

Nonetheless, when it is taken in high doses for a long time, it can lead to the loss of important minerals in the body, which can result in diarrhea, strong headaches, dehydration, weight loss, pancreatitis, changes in cardiac conductivity and muscular weakness.

When to avoid using it

Horsetail is not recommended for use by pregnant women or breastfeeding women, nor by people with a history of cardiac failure, low blood pressure and kidney disease. Horsetail can decrease the body's ability to decrease blood pressure and has a strong diuretic effect.

Was this information helpful?

Atualizado por Tua Saude editing team, em January de 2022. Clinical review por Manuel Reis - Registered Nurse, em January de 2022.

References

  • MIMICA-DUKIC, Neda; et al. Phenolic Compounds in Field Horsetail (Equisetum arvense L.) as Natural Antioxidants. Molecules. 13. 7; 1455–1464, 2008
  • SAUDELLI, Gabriele Saudelli; TINTI, Laura; SUFFRITTI, Giovanni. A Review on the Treatment of Osteoporosis with Equisetum arvense. Gen Med (Los Angeles). 6. 2; 1-5, 2018
Show more references
  • KOTWAL, Swati D.; BADOLE, Smita R. Anabolic therapy with Equisetum arvense along with bone mineralising nutrients in ovariectomized rat model of osteoporosis. Indian J Pharmacol. 48. 3; 312–315, 2016
  • WRIGHT, C. I.; et al. Herbal medicines as diuretics: a review of the scientific evidence. J Ethnopharmacol. 114. 1; 1-31, 2007
  • CARNEIRO, Danilo Maciel Carneiro; 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. 760683; 1-8, 2014
  • GRUNDEMANN, Carsten; et al. Equisetum arvense (common horsetail) modulates the function of inflammatory immunocompetent cells. BMC Complement Altern Med. 14. 283; 1-10, 2014
  • PALLAG, Annamaria; et al. Equisetum arvense L. Extract Induces Antibacterial Activity and Modulates Oxidative Stress, Inflammation, and Apoptosis in Endothelial Vascular Cells Exposed to Hyperosmotic Stress. Oxid Med Cell Longev. 2018. Feb 14; 3060525, 2018
  • MASLOWSKI, Marcin; et al. Horsetail ( Equisetum Arvense) as a Functional Filler for Natural Rubber Biocomposites. Materials (Basel). 13. 11; 2526, 2020
  • AGÊNCIA NACIONAL DE VIGILÂNCIA SANITÁRIA. Memento Fitoterápico. 2016. Available on: <http://portal.anvisa.gov.br/documents/33832/2909630/Memento+Fitoterapico/a80ec477-bb36-4ae0-b1d2-e2461217e06b>. Access in 13 Nov 2019
  • FINTELMANN, Volker.; WEISS, Rudolf F. Manual de fitoterapia. 11ª edição. Rio de Janeiro: Guanabara Koogan, 2010. 255-257.
  • MOURA, Maria F.. Segredos e virtudes das plantas que curam. 1.ed. Lisboa: Seleções, 2011. 72-73.
  • FLORIEN. Cavalinha. Available on: <http://florien.com.br/wp-content/uploads/2016/06/CAVALINHA-1.pdf>. Access in 02 Apr 2019
  • INFINITY PHARMA. Cavalinha - fitoterápico. 2017. Available on: <https://infinitypharma.com.br/uploads/insumos/pdf/c/cavalinha.pdf>. Access in 02 Apr 2019
  • HERBARIUM. Cavalinha: Equisetum arvense L., Equisetaceae. Available on: <http://www.saudedireta.com.br/catinc/drugs/bulas/cavalinha.pdf>. Access in 02 Apr 2019
  • SPARAVIGNA, Adele; et al. Equisetum arvense in a new transungual technology improves nail structure and appearance. Journal of Plastic Dermatology. 2. 1; 31-38, 2006
Clinical review:
Manuel Reis
Registered Nurse
Manuel graduated in 2013 and is licensed to practice under the Ordem dos Enfermeiros de Portugal, with license #79026. He specializes in Advanced Clinical Phytotherapy.