BACKGROUND:Sassafras usually refers to an oil or tea made from the tree, Sassafras albidum. This is native to eastern regions of North America and was widely used by Native Americans both to treat many ailments and to flavour dishes. The root was one of the main ingredients in root beer, which quickly led to it becoming the second most popular export from the New World (with tobacco being the most popular).
Root beer remains a very popular beverage in the US, especially its non-alcoholic brands. Root beer gets its name because it is made from extracts of the roots of several herbs. A number of other spices are then added to give each brand its distinctive flavour. While sassafras continues to be the root listed as most prevalent among the ingredients, artificial flavouring agents are almost always used nowadays. Most manufacturers changed their recipe in this way after serious concerns were raised about the safety of sassafras oil in the 1970s.
Among enthusiasts of herbal teas and remedies, sassafras has become popular again. The tea is usually recommended as a general tonic and blood purifier or specifically as a treatment for syphilis, while the oil is usually restricted to external application. This application is usually recommended for various skin conditions and to treat insect bites and stings.
EVIDENCE FROM STUDIES
In spite of its long history of traditional use, no clinical trials in humans could be found. Sassafras was widely used in cooking and beverages, but studies in animals in the 1960s and 1970s raised concerns. Sassafras root bark contains about 5 to 10 per cent safrole, mostly present in the oil. These early animal studies showed that safrole permanently damaged the liver, causing cancer in many of the animals. These studies led the US regulatory agency, the Food and Drug Administration (FDA), to ban the use of sassafras and safrole in foods and drinks.
In 1994, new legislation in the US led to sassafras becoming readily available again. This legislation allows herbs and their products to be marketed as dietary supplements without having to demonstrate effectiveness or safety. As a result, sassafras has once again grown in popularity and is readily available in the US and on the internet. In spite of the renewed interest, however, no new studies have been published.
PROBLEMATIC ASPECTS
Early concerns about sassafras arose when an adult died after ingesting one teaspoonful of sassafras oil. A small number of young children also died after consuming a few drops of the oil. Safrole is thought to be the most toxic component, and currently available sassafras products are expected to have all safrole removed. However, questions have been raised about how thoroughly this can be done as it is very difficult to remove all traces from the plant material. Safrole remains highly restricted because it can be chemically converted into the illegal street drug MDMA or ecstasy. Various central nervous systems side effects have been reported by people using sassafras for extended periods of time.
RECOMMENDATIONS
Debate continues over whether the amount of sassafras and safrole used in the early animal studies exceeded the amounts which people are likely to consume in herbal products. Some claim one strong cup of sassafras tea contains enough safrole to cause liver damage; others claim huge volumes of tea would be necessary to cause any problems.
In situations where serious side effects are possible, significant beneficial effects would be needed to warrant taking these risks. Such benefits have never been demonstrated in controlled studies. For that reason, the use of sassafras products for any condition, especially the treatment of a serious condition like syphilis, cannot be recommended.
Dónal OMathúna has a PhD in pharmacy, researching herbal remedies, and an MA in bioethics, and is a senior lecturer in the School of Nursing, Dublin City University. He is author of Alternative Medicine: The Christian Handbook, Updated and Expanded Edition, Zondervan, 2007
