Rooibos (pronounced ROY-boss) is a flowering bush of the legume family grown in the Cedarberg Mountain region of South Africa. It is used to make a caffeine-free tisane that has gained popularity for the notable levels of polyphenol antioxidants it contains.¹ Recently, antioxidants—substances found in food and tea that scientists believe help fight against damage caused by free radicals which are thought to cause premature aging, cancer and other illnesses—have become the buzz of the natural foods and health movements. Rooibos (Aspalathus linearis), strictly speaking, is not a tea since it does not come from the Camellia sinensis plant, but rather a tisane. It differs from tea, also, in that rooibos is nearly free of tannins, which can give true teas an astringent quality when they're brewed too long. On the contrary, the longer rooibos is brewed, the more flavorful it becomes. Its flavor can be described as fruit forward and it tastes, slightly, like it's been fortified with almonds and citrus. Although rooibos is harvested green, the bulk of it is processed by means of crushing and bruising, which causes fermentation and imparts rooibos's distinctive red color, flavor, and scent, before being sun-dried.²

The health claims for drinking rooibos derive from its high level of polyphenol group antioxidants, of which flavonoids and phenolic acids—potent free radical predators--are subgroups.³ Two flavonoids present in rooibos are quercetin and luteolin, which in vitro studies have been shown to cause apoptosis (self destruction) of carcinogenic cells,^4-7 but they represent a small fraction of the total flavenoids present in rooibos, which, likewise, represent a small portion of the total polyphenol antioxidants (as yet unidentified or quantified) in a serving of fermented rooibos tea. ⁸ Other laboratory tests done on mice indicate that rooibos may fight mutagens—changes in animal cells connected with cancer.⁹ Although human studies still need to be done, evidence for rooibos's antioxidant power, so far, looks promising. Studies indicate that antioxidants taken as whole foods, such as tea, herbal infusions, berries, or vegetables, have a greater benefit than isolated antioxidants. Apple extracts were more effective than quercetin, tomato powder better than isolated leucopenia, and freeze-dried strawberries better than pure pelagic acid.¹⁰

Although much more study is needed, these preliminary reports indicate that rooibos's popularity as a tasty, caffeine-free drink may be bolstered by its richness in antioxidants. It appears to be safe, to have the potential to guard the body against cancers, heart disease, and other illnesses, and it exhibits no known side effects. It will be exciting, as time passes, to see what the future brings in our knowledge of rooibos, its antioxidant properties, and its apparent benefits to human health.¹¹

References

1. Erickson, L. Rooibos Tea: Research into Antioxidant and Antimutagenic Properties, HerbalGram. 2003;59:34-45.

2. Erickson, L. Rooibos Tea: Research into Antioxidant and Antimutagenic Properties, HerbalGram. 2003;59:34-45.

3. Erickson, L. Rooibos Tea: Research into Antioxidant and Antimutagenic Properties, HerbalGram. 2003;59:34-45.

4. Lee LT, Huang YT, Hwang JJ, Lee PP, Ke FC, Nair MP, Kanadaswam C, Lee MT. Blockade of the epidermal growth factor receptor tyrosine kinase activity by quercetin and luteolin leads to growth inhibition and apoptosis of pancreatic tumor cells. Anticancer Res 2002;22(3):1615-27, cited in Erickson, L. Rooibos Tea: Research into Antioxidant and Antimutagenic Properties, HerbalGram. 2003;59:34-45

5. Mouria M, Gukovskaya AS, Jung Y, Buechler P, Hines OJ, Reber HA, Pandol SJ. Food-derived polyphenols inhibit pancreatic cancer growth through mitochondrial cytochrome C release and apoptosis. Int J Cancer 2002;98(5):761-9, cited in Erickson, L. Rooibos Tea: Research into Antioxidant and Antimutagenic Properties, HerbalGram. 2003;59:34-45

6. Yamashita N, Kawanishi S. Distinct mechanisms of DNA damage in apoptosis induced by quercetin and luteolin. Free Radic Res 2000;33(5):623-33, cited in Erickson, L. Rooibos Tea: Research into Antioxidant and Antimutagenic Properties, HerbalGram. 2003;59:34-45

7. Roy Chowdhury A, Sharma S, Mandal S, Goswami A, Mukhopadhyay S, Majumder HK. Luteolin, an emerging anti cancer flavonoid, poisons eukaryotic DNA topoisomerase I. Biochem J 2002;366(Pt 2):653-61, cited in Erickson, L. Rooibos Tea: Research into Antioxidant and Antimutagenic Properties, HerbalGram. 2003;59:34-45

8. Joubert, E. Personal communication. First reference Nov 2002, all other references Aug 2002, cited in Erickson, L. Rooibos Tea: Research into Antioxidant and Antimutagenic Properties, HerbalGram. 2003;59:34-45

9. Erickson, L. Rooibos Tea: Research into Antioxidant and Antimutagenic Properties, HerbalGram. 2003;59:34-45.

10. Joseph J, Nadeau D, Underwood A. The Color Code: A Revolutionary Eating Plan For Optimal Health, Hyperion, New York, 2002, p. 8-10, 33, 44, 57, cited in Erickson, L. Rooibos Tea: Research into Antioxidant and Antimutagenic Properties, HerbalGram. 2003;59:34-45.

11. Erickson, L. Rooibos Tea: Research into Antioxidant and Antimutagenic Properties, HerbalGram. 2003;59:34-45.