The kola nut is the fruit of the kola tree (Cola nitida), indigenous to West Africa. The trees, which reach heights of 40 to 60 feet, produce a star-shaped fruit. Each fruit contains between two and five kola nuts. About the size of a chestnut, this little fruit is packed with caffeine. Each nut contains more caffeine than two large cups of American coffee. In the West (the United States and Europe), you are more likely to encounter kola nut extract than the fresh nut itself. Kola extract is a common food flavoring found in Coca-Cola, Pepsi-Cola, and now many popular energy drinks.