Caffeine occurs naturally in tea. A mild stimulant, it accounts for tea’s reputation as a beverage that clears the mind and lifts the spirit.
On average, a six-ounce cup of black tea has about 50 milligrams of caffeine—less than half the amount in a cup of brewed coffee. The smaller the leaf, the stronger the extraction of caffeine. Using comparable amounts and steeping times, a tea bag filled with cut leaves will release more caffeine per cup than full-leaf tea.