Rooibos (pronounced roy-boss), also known as red tea or redbush tea, hails from South Africa. Its leaves and stems are fermented, lending its rich, red color. It is not a true tea (from a tea plant), but a tisane (an herbal tea). It has a warming, earthy flavor and is naturally caffeine-free. Rooibos contains powerful antioxidants that have been shown to have a relaxing effect on the central nervous system, including lowering cortisol levels in the body.