One of the most popular mind-altering stimulants has prehistoric roots

The prehistoric remains of two foragers found on the Indonesian island of Sulawesi contain telltale signs that humans began using a mind-altering drug thousands of years earlier than known.

The betel nut, a fruit seed from the areca palm, is considered the fourth most widely used psychoactive substance in the world after caffeine, alcohol and nicotine.

About 1 in 10 people today, largely across Asia and the Pacific, practice the tradition of chewing a quid, or processed betel nut mixed with slaked lime.

The slaked lime, also known as calcium hydroxide, is essential for