Give a scientist one strand of your hair and they can tell your ethnic origin, environment, diet and even lifestyle. Researchers from London’s Natural History Museum say our hair traps within its physical and chemical structure an accurate record of whatever has been ingested or applied to it externally. (An Impossible Question follows, read on) Since your hair only grows 0.3 to 0.5 millimeters a day, it keeps a life diary for a long time — months or even years. Your hair can tell if you smoke, drink or take drugs. More hair facts:

• The average person has up to 150,000 hairs on his or her the head.
• A single strand can support 100 grams in weight.
• African hair grows more slowly and is more fragile than European hair.
• Asian hair grows the fastest and has the greatest elasticity.
• Africans and Europeans are more prone than Asians to balding.

Impossible Question: What’s the one thing about you that your hair cannot reveal? (Your gender)