Rooibos (Aspalathus linearis) is a flowering shrub native to the mountains of South Africa’s Western Cape that is used to make a mild-tasting, caffeine-free, low tannin herbal tea. Although Rooibos is fairly new or unknown to many in North America, it has been consumed in South Africa for hundreds of years. However, its potential health-promoting properties, most notably its antioxidant activity, has contributed to its increasing popularity around the world.
There are a number of varieties of wild rooibos that have been used to make tea, sometimes referred to as the Red, Black, Grey, and Red-Brown types. The variety cultivated commercially for tea is the Red type, native to the northern Cedarberg region.
Rooibos is processed in two different ways, producing two types of tea. The harvested green leaves and stems are either bruised and fermented, or immediately dried to prevent oxidation. If fermented, the resulting tea is called red tea because fermentation turns the leaves and the resulting tea a rich orange/red color (inspiring its Afrikaans’ name rooibos, which means "red bush"). The unfermented type, called green rooibos, makes a tea that is tan/yellow in color.
Numerous animal and in vitro studies show that rooibos has potent antioxidant effects, and has been found to contain significant amounts of polyphenol antioxidants. Antioxidants have been shown to help protect against various metabolic diseases, heart disease, brain disorders and age-related syndromes, as they help the body combat cellular damage caused by free radicals (reactive chemicals containing oxygen).
Studies show that the unfermented variety of rooibos contains higher levels of antioxidants, which is thought to be attributable to enzymatic and chemical changes that fermented rooibos undergoes during the fermentation process. However, the fermented variety has still been found to have antioxidant power. In fact, it was even shown to decrease oxidation of fats in the liver.