In our segment health and fitness expert, Dr Garry Egger, talked about the purpose of hair on the body.
The insulating properties of hair
Hair keeps us warm, just like a blanket, but it also cools us off. Cooling only occurs when sweat evaporates. If sweat drops off the skin or stays on the skin, no significant cooling will occur. Hair cools down the body by collecting sweat and slowing down the evaporation of sweat off the skin. So it is logical that we have hair under the arms, around the groin and on the arms and legs.
Why have hair on the head?
Evaporation and cooling occurs increasingly with height, so hair on the head is a great way of cooling the body and particularly that heat sensitive organ, the brain. In hot parts of the world, native people often have tight, curly hair which slows down the rate of sweat loss, and hence increases cooling. This could explain why humans kept the hair on their heads but lost it on other parts of their bodies as they evolved and began to walk upright on two legs.
Further information
Dr Garry Egger started GutBusters, a scientifically based program which uses waist measurement, not weight, as an indication of fat loss in men. To contact GutBusters phone 1800 674 688, or visit their website: http://www.gutbusters.com.au