By Harini Gopalswami Srinivasan

From prehistoric times, human beings have treated their diseases with natural herbs and minerals, in much the same way that a dog will nibble grass to cure an upset stomach, or a deer will lick salt to keep all its organs in working order.

The first documented knowledge about medicines in India is found in the Rig Veda (Oshadhi Sooktam) and the Atharva Veda, which are believed to be more than 5000 years old. In addition to providing mantras against diseases and information about useful plants and herbs, the Atharva Veda says that diseases are caused by......