Interesting facts about the Human Body

Interesting facts about our hair

1. Hair consists of proteins (65% - 95%), lipids (1% - 9%), trace elements, polysaccharides and water. One of the main proteins is keratin which contains sulphur, which adds strength to the hair and is produced in the keratogen zone of the root.

2. There are three types of hairs:

Lanugo hairs which cover the embryos body from the 3rd month of pregnancy until a few weeks before birth.

Vellus hairs, which appear to be virtually invisible emerging from hair follicles with no sebaceous glands.

Terminal hairs, which are the more common and noticeable hair that emerges from follicles with sebaceous glands.

3. Due to its strength, when wet hair can be stretched up to 30% of its own length, this is mostly due to the protein conformation of the keratin, a protein that can be found all over the animal kingdom presented as hooves, horns and even in our own fingernails.

4. What is the most common hair colour?

Let's start with the least common, this being the colour red which is thought to be around 1% of the world's population, blond hair being the second least common with only 2%, brown hair being the third least common and black hair being the most common.

5. A scientific study was conducted into how women perceived men with facial hair at different stages of growth. Women tended to rate men being most attractive at the stages where hair was noted to be as heavy stubble. The healthiest in appearance appeared to be subjects that had no facial hair. But men with a full facial beard were noted to be more masculine and were also ascribed to have the best parenting skills.

6. Hair growth has been found to grow much faster in a warmer climate. This is mostly due to the fact that blood circulation is more prominent due to the blood vessels being dilated allowing the hair follicles to be supplied with more of the nutrient and compounds it requires for growth.

7. A strand of hair is actually widely used is forensic evidence, this for many reasons those being, for the detection of many therapeutic drugs and recreational drugs, for DNA analysis only when the root of the hair is attached, also hair can be used to match blood relatives, to test for poisoning caused by metals such as lead or mercury, plus many more. However, hair analysis cannot identify your gender. So, here a good tip, don't leave your hair at the crime scene.

8. What is the purpose of having hair on our bodies?

Although hairs can sometimes be nearly invisible they do play a significant role in heat regulation. As I am sure most people have noticed that when they are cold they get these little bumps known as goose bumps. These bumps appear due to the pili muscle which is attached to the hair follicle contracting pulling the bottom of the hair allowing each hair strand to stand up. In effect this technique allows the hair to trap a layer of body heat helping you stay warmer.

9. Does your hair really stand on end when scared?

Well the answer to this is yes!

When you are scared or threatened the body gets a sudden release of the hormone adrenaline, which acts as a natural stimulant increasing your heart rate, dilating your blood vessels allowing the muscles to be supplied with lots of energy. This effect also causes our hair to stand on end. This is thought to be an evolution trait which is not needed as such now.

The idea behind this technique is to make us look bigger as you would see in a cat if chased by a dog, there back arches and their hair stands up.

10. Still keeping to the same subject of hair standing on end, well this technique also happens in different occasions, usually related to emotional states, such as excitement, you may know it as a 'sudden chill'. Studies have shown in occasions when this occurs the hypothalamus is activated. The hypothalamus plays a key role in the primal drive for hunger, rage and sexual arousal.

The initial study was conducted when subjects was listening to powerful music that created an emotional response. It is thought that people who experience the 'chills' more often than overs are found to be open mind, creative, curious and are happy to take on new adventures.

The evolutionary advantage for this technique is still very much unclear.