Horse chestnut as a dietary supplement
Horse chestnut, derived from the seeds of the Aesculus hippocastanum tree, is utilized as a dietary supplement primarily for its potential benefits in treating venous insufficiency and related conditions. This natural herbal product contains active compounds known as saponins, with aescin being the most significant, which may help reduce swelling and inflammation. Traditionally, horse chestnut has been used for various ailments, including hemorrhoids, minor injuries, and edema.
Clinical studies suggest that horse chestnut may alleviate symptoms associated with venous insufficiency, such as leg pain and swelling, and may also provide relief for hemorrhoids. However, while some research supports its effectiveness, further high-quality studies are needed to fully establish its benefits and safety. It is crucial to note that whole horse chestnut can be toxic if consumed improperly, and only standardized extracts should be used, as they are prepared to remove harmful constituents.
Safety considerations include avoiding use with certain anticoagulant medications and being cautious with individuals who have kidney issues or are pregnant. Overall, horse chestnut may be a useful supplement for specific health concerns, but it should be approached with care and ideally under medical supervision.
Horse chestnut as a dietary supplement
DEFINITION: Natural plant product used as a dietary supplement for specific health benefits.
PRINCIPAL PROPOSED USE: Venous insufficiency
OTHER PROPOSED USES: Hemorrhoids, minor injuries, phlebitis, edema, male infertility, inflammation, pain
Overview
The horse chestnut tree is widely cultivated for its bright white, yellow, or red flower clusters. Closely related to the Ohio buckeye, this tree produces large seeds known as horse chestnuts. A superstition in many parts of Europe suggests that carrying these seeds in one’s pocket will ward off rheumatism. More serious medical use dates back to nineteenth-century France, where extracts were used to treat hemorrhoids.
Therapeutic Dosages
The most common dosage of horse chestnut is 300 mg twice daily, standardized to contain 50 mg aescin per dose, for a total daily dose of 100 mg aescin. Horse chestnut preparations should certify that a toxic constituent called esculin has been removed. Also, a delayed-release formulation should be used to prevent gastrointestinal upset.
Therapeutic Uses
German research of this herb began in the 1960s and ultimately led to the approval of a horse chestnut extract for vein diseases of the legs. Horse chestnut is Germany's third most common single-herb product, after ginkgo and St. John’s wort. In Japan, an injectable form of horse chestnut is widely used to reduce inflammation after surgery or injury. Still, it is unavailable in the United States and may present safety risks.
The active ingredients in horse chestnut appear to be a group of chemicals called saponins, of which aescin is considered the most important. Aescin appears to reduce swelling and inflammation. It is not clear how aescin might work, but theories include “sealing” leaking capillaries, improving the elastic strength of veins, preventing the release of enzymes (known as glycosaminoglycan hydrolases) that break down collagen and opening holes in capillary walls, decreasing inflammation, and blocking other various physiological events that lead to vein damage.
Horse chestnut is often used as a treatment for venous insufficiency—a condition associated with varicose veins when the blood pools in the veins of the leg and causes aching, swelling, and a sense of heaviness. While horse chestnut appears to reduce these symptoms, few studies have evaluated whether it can make visible varicose veins disappear or prevent new ones from developing.
Because hemorrhoids are a form of varicose veins, horse chestnut is also used for them, and one double-blind, placebo-controlled study suggests that it may be effective. Another double-blind study found that a topically applied gel made from horse chestnut may be helpful for bruises. Oral horse chestnut has also been proposed for minor injuries and surgery, but published studies on this potential use were not double-blind.
Horse chestnut is sometimes used with conventional treatment in cases where the veins of the lower legs become seriously inflamed (called phlebitis). Note, however, that phlebitis is potentially dangerous and requires a doctor’s supervision. Similarly, horse chestnut’s ability to improve blood circulation and reduce inflammation may also help with edema or fluid retention in body tissues. Some suggest horse chestnut can improve sperm quality and motility in men with swollen veins in the scrotum. Finally, horse chestnuts may relieve arthritis and muscle soreness due to their anti-inflammatory properties.
Scientific Evidence
Venous insufficiency. Many individuals have been involved in double-blind, placebo-controlled studies of horse chestnut for treating venous insufficiency.
One of the largest of these trials followed 212 people for forty days. In this crossover study, participants initially received horse chestnut or a placebo and then were crossed over to the other treatment (without their knowledge) after twenty days. The results showed that horse chestnut significantly improved leg edema, pain, and sensation of heaviness. However, the design of this study was not up to modern standards.
A better-designed double-blind study of seventy-four people also found benefit. Good results were seen in a partially double-blind, placebo-controlled study, which compared the effectiveness of horse chestnut to that of compression stockings, a standard treatment. This study followed 240 people for twelve weeks. Compression stockings worked faster at reducing swelling, but by the end of the study, the results were equivalent, and both treatments were better than the placebo. However, a small double-blind trial suggests that oligomeric proanthocyanidins (OPCs) from pine bark are more effective than horse chestnut for treating venous insufficiency.
Hemorrhoids. A double-blind, placebo-controlled study of eighty people with symptomatic hemorrhoids evaluated the use of a horse chestnut product providing 40 milligrams (mg) of aescin three times daily. The results indicated that the use of horse chestnut produced noticeable subjective improvements in pain, bleeding, and swelling within one week. Within two weeks, the benefits were visible by objective examination.
Bruises. A double-blind study of seventy people found that about ten grams of 2 percent aescin gel, applied externally to bruises in a single dose five minutes after they were induced, reduced bruise tenderness.
Male Infertility. One two-month study of over 100 men with varicocele-associated infertility—or infertility related to swollen glands in the scrotum—found supplementation with 30 mg of aescin improved sperm density, motility, and quality.
Safety Issues
The US Food and Drug Administration categorizes whole horse chestnut as an unsafe herb. Eating the nuts or drinking a tea made from the leaves can cause horse chestnut poisoning, the symptoms of which include nausea, vomiting, diarrhea, salivation, headache, breakdown of red blood cells, convulsions, and circulatory and respiratory failure, possibly leading to death. However, manufacturers of the typical European standardized extract formulations remove the most toxic constituent (esculin) and standardize the quantity of aescin. To prevent stomach irritation caused by another ingredient of horse chestnut, the extract is supplied in a controlled-release product, which reduces the incidence of irritation to below 1 percent, even at higher doses.
Properly prepared horse chestnut products appear to be quite safe. After decades of wide usage in Germany, there have been no reports of serious harmful effects, and even mild reported reactions have been few.
In animal studies, horse chestnut and its principal ingredient, aescin, have shown low toxicity, producing no measurable effects when taken at dosages seven times higher than normal. Dogs and rats have been treated for thirty-four weeks with this herb without harmful effects.
Persons with severe kidney problems should avoid horse chestnut. In addition, injectable forms of horse chestnut can be toxic to the liver. The safety of horse chestnut in children and pregnant or nursing women has not been established. However, thirteen pregnant women were given horse chestnut in a controlled study without noticeable harm. Furthermore, studies in pregnant rats and rabbits found no injury to embryos at doses up to ten times the human dose and changes of questionable significance at thirty times the dose.
Finally, horse chestnut should not be combined with anticoagulants or blood-thinning drugs, as they may amplify their effect.
Important Interactions
One should not use horse chestnut without medical supervision if also taking aspirin, clopidogrel (Plavix), ticlopidine (Ticlid), pentoxifylline (Trental), or anticoagulant drugs, such as warfarin (Coumadin) or heparin.
Bibliography
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Fang, Yujiang, et al. "Escin Improves Sperm Quality in Male Patients with Varicocele-Associated Infertility." Phytomedicine: International Journal of Phytotherapy and Phytopharmacology, vol. 17, no. 3-4, 2010, pp. 192-96.
Kharlamenko, Alena. "7 Health Benefits of Horse Chestnut Extract." Healthline, 13 July 2023, www.healthline.com/nutrition/horse-chestnut-benefits. Accessed 5 Sept. 2024.
Koch, R. "Comparative Study of Venostasin and Pycnogenol in Chronic Venous Insufficiency." Phytotherapy Research, vol. 16, suppl. 1, 2002, pp. S1-S5.
Multum, Cerner. "Horse Chestnut." Drugs.com, 22 Feb. 2024, www.drugs.com/mtm/horse-chestnut.html. Accessed 5 Sept. 2024.
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