Black tea is produced in China, Taiwan, India, Sri Lanka, and Indonesia. Processing varies across the regions but involves withering, rolling, fermenting, and drying or firing.
Black tea is the only fully fermented tea. It has the lowest amounts of antioxidants, but the highest caffeine concentration, and has been used for:
- heart and circulatory system stimulation
- the prevention of stroke and heart disease
- the prevention of cholesterol absorption
- lowering blood pressure
- the support of oral health