Unsweetened brewed green tea is a zero calorie beverage. The caffeine contained in a cup of tea can vary according to the length of infusing time and the amount of tea infused. In general, green tea contains a relatively small amount of caffeine (approximately 20-45 milligrams per 8 ounce cup), compared with black tea, which contains about 50 milligrams and coffee with 95 milligrams per cup.
Rooibos tea is anti-inflammatory in nature, which means that it reduces blood pressure and scavenges free radicals like other antioxidants. Quercetin, another powerful antioxidant found in rooibos tea, has been linked to preventing a wide variety of heart conditions. It promotes an increase in HDL cholesterol (good cholesterol) and inhibits the LDL cholesterol (bad cholesterol) from binding to the walls of arteries and blood vessels.