Rooibos (pronounced ROY-boss), which is Afrikaans for "red bush," has been popular for generations in South Africa, where it's often served with milk and sugar. Now it's become a hit among health-conscious consumers in the U.S., mostly because of its high level of antioxidants, low level of tannins and lack of caffeine.
Rooibos "tea" is made from the leaves and stems of Aspalathus linearis, a shrub in the legume family that grows only in the Cederberg region of the West Cape Province in South Africa. It can grow up to 3 feet tall, sports red colored stems and is covered with dark green needle-shaped leaves.
Rooibos leaves and stems are fermented to produce the distinctive reddish-brown color, hence the name "red tea" or "red rocker," describing the color of the brew. Unfermented rooibos tea, distinguished by its yellow color, has a higher level of antioxidants.
Ancient Folk Medicine
In South Africa, rooibos is folk medicine, used to treat colic and diaper rash in infants, and digestive problems, skin allergies, eczema, and sleep disorders in adults. More research is necessary to determine whether these folk remedies work dependably, although research reported last November in Basic and Clinical Pharmacology and Toxicology noted potential antispasmodic and antidiarrheal activity of some of the naturally occurring compounds in rooibos.
Does rooibos tea offer protection against cancer, heart disease and stroke as enthusiasts claim? Certainly the unique beverage has potential if one judges by its impressive list of phytochemicals. Plants employ a class of compounds called polyphenols to serve as pigments, and to guard against UV light and oxidative damage. Polyphenols are divided into subgroups called flavonoids and phenolic acids (see "Phytochemical A-B-Cs,"), and about 10 flavonoids form the bulk of the rooibos protective arsenal; they go by tongue-twisting names like aspalathin, nothofagin, quercetin, rutin, isoquercitrin, orientin, isoorientin, luteolin, vitexin, isovitexin, and chrysoeriol. Rooibos also contains phenolic acids, substances found in fruits, vegetables, and whole grains that have known antioxidant activity.
A cup of rooibos tea is lower in total polyphenols than a cup of green or black tea, but the types of polyphenols are different, so the potential health benefits cannot be judged solely on total polyphenol content. While rooibos tea is lacking epigallocatechin gallate (EGCG), the antioxidant polyphenol in green tea shown to be anticarcinogenic, its many other phytochemicals are strong antioxidants in their own right.
Quercetin and luteolin flavonoids in rooibos tea are potent antioxidants found in many fruits and vegetables. Lab studies indicate these antioxidants can force cancer cells to undergo programmed cell death and may also act as powerful anti-inflammatory agents. Moreover, rooibos is currently the only known natural source of aspalathin, one of the most abundant flavonoids in rooibos tea. Aspalathin acts as a powerful antioxidant in laboratory studies, as does nothofagin, a flavanoid of similar structure.
Many other rooibos polyphenols are yet to be identified but two -- orientin and rutin -- were shown to protect human blood cells exposed to radiation from cancer-associated changes. In animal studies, orientin prevented oxidative damage to the liver and reduced damage to the bone marrow and gastrointestinal tract. And rutin, a flavonoid generally found in buckwheat and in some fruits and vegetables, may to help strengthen capillary walls.
Rats given daily free access to fermented rooibos tea from the age of three months to 24 months showed a reduction in age-related lipid peroxide accumulation in four areas of their brains. Excess lipid peroxides in the brain can spell damage to neuronal cells and contribute to age-related diseases. There is ongoing research into the protective effect of rooibos on liver, esophageal, colon, and skin cancer induced in animal subjects.
More than the Sum
Full benefits of rooibos teas are likely to come from the combination of all the antioxidants rather than from one lone substance. Also, powerful antioxidants, when isolated can become powerful oxidants.
Although many of the human health claims made for rooibos are anecdotal, while this research continues, you can feel pretty good about a tea that's so rich in antioxidants, caffeine-free and low in bitter tannins. So rock on!