More than a third of American adults use some form of complementary or alternative medicine, according to a government report. Natural remedies have an obvious appeal, but how do you know which ones to choose and whether the claims are backed by science? In this occasional series, Anahad O’Connor, the New York Times “Really?” columnist, explores the claims and the science behind alternative remedies that you may want to consider for your family medicine cabinet.
The Remedy: Horse chestnut seed extract.
The Claim: It helps relieve leg pain and other symptoms of venous insufficiency.
The Science: Poor blood flow in the veins of the legs is one of the common problems that develop as we age.
But when the problem becomes severe enough, it can result in a condition called chronic venous insufficiency. People who have the condition can find themselves struggling with a host of bothersome symptoms like leg pain, pruritus (itchiness), hardening of the skin and edema (swelling of tissue under the skin).
Wearing compression socks or stockings, one of the more traditional solutions, can be helpful but also uncomfortable for some people, causing them not to use them. But one alternative remedy, popular in Europe, is to use extracts from the seed of the horse chestnut, a large and leafy tree native to the Balkans and other parts of Europe. The extract contains beta-aescin and other compounds believed to help strengthen blood vessel walls and reduce swelling and redness.
Over the years, numerous studies have examined whether horse chestnut can actually make a difference. Most have found that it works well, but some studies have either suffered from poor design or were financed in part by commercial interests.
But in 2006, scientists with the Universities of Exeter and Plymouth in England sifted through years of studies and selected the best randomized controlled trials for a meta-analysis in the respected Cochrane Database of Systematic Reviews.
“Over all,” they found, “the trials suggested an improvement in the symptoms of leg pain, edema and pruritus with horse chestnut seed extract when taken as capsules over two to 16 weeks.”
Most of the trials found horse chestnut more effective than placebo, and one of them — a study published in The Lancet in 1996 — found that taking 50 milligrams of aescin (the active ingredient in horse chestnut seed) twice daily over 12 weeks worked just as well as wearing compression stockings.
“The evidence presented implies that horse chestnut seed extract is an efficacious and safe short-term treatment for chronic venous insufficiency,” the authors of the Cochrane report concluded. But they also added the caveat that more rigorous studies were needed “to confirm the efficacy of this treatment option.”
The Risks: According to the National Institutes of Health, horse chestnut seed extract can cause side effects like nausea, itchiness and stomach upset. The agency also advises never to use homemade preparations, and points out on its Web site that while the extract is safe when properly processed, raw horse chestnut seeds, leaves, bark and flowers contain a chemical called esculin that is toxic.
