What are Best Sources of Caffeine?

Caffeine is addictive and among the world's most prevalently used drug. It is found naturally or added artificially in different types of foods and beverages. Nearly 30% people in U.S. consume caffeine daily in one way or other. Each and every year over 120,000 tons of caffeine is consumed. Caffeine is good for health if it is consumed in small amount or moderation (250 milligrams) daily. It