Want to know some facts about your hair? I can’t claim to tell you everything you need to know about hair, but you’ll be better informed than before you read this article... and I’m sure you’ll find these facts about your hair interesting.
1. The Biology of Hair
There are essentially 2 parts to a human hair – the root and the shaft. The root sits in a well in the skin called a follicle, which contains sebum (oil) producing glands and a dermal papilla, which provides the nutrients for the hair to grow. The hair outside the skin – i.e. the visible bit, is the shaft. The facts about hair should also explain that the shaft is made up of 3 layers; a core of central cells called the medulla, a layer of protein fibers called the cortex, and finally, a layer of overlapping keratin cells called the cuticle. The composition of hair is generally 51% carbon, 21% oxygen, 17% nitrogen, 6% hydrogen and 5% sodium.
2. Chains and Bonds
A hair strand is roughly 91% protein made of chains of amino acids held together by polypeptide chains and three types of side bonds – hydrogen bonds, salt bonds and disulfide bonds. The first two types of bonds are in the majority but are also weaker than disulfide bonds and more susceptible to heat and moisture.
3. Breaking Bonds
It is these facts about your hair that govern how treatments are made to work. Wet roller sets, curling irons, straighteners and hair dryers act on the salt and hydrogen bonds, changing the amount of curl in the hair. When you have a perm or relaxing treatment, the strong chemicals in them are working to break and reform the disulfide bonds.
4. How It Grows
A strand of hair is lengthened by the creation of new cells at the root. As the new cells are added and built up, they push the strand further out from the follicle. Essentially, hair outside your scalp is technically “dead.”
5. Growth Rate
Although the rate at which hair grows varies by individuals and factors such as genetics, age, diet, environment, etc., generally hair grows at an average of half an inch (about 1cm) each month – this is roughly 0.35mm per day. This equates roughly to 6 inches every year. Hair also grows at the same speed all over your head.
6. Facts about Hair Growth
Did you know that hair grows faster in the summer than in winter? Did you also know that it grows faster during the night than in the daytime? And also, among the other things you should know about your hair is that it grows more quickly between the ages of 16 and 24.
7. The Lifeline of Hair
Hair has 3 stages in its lifetime. One, the Anagen – new hair cells grow in the hair bulb. Two, the Catagen – cell division ceases and hair stops growing. Three, the Telogen – a new strand forms and the old (dead) strand falls out. A single healthy hair strand generally lives between 2-7 years. The telogen stage usually lasts about 3 months for each hair.
8. How Long?
If you were to never cut your hair it would grow to reach a length of 42 inches. However, the lifetime of hair dictates the maximum length an individual’s hair can grow. On average, waist length hair takes roughly 6 years to grow (including any trims to remove split ends and tidy up). If however, your hair only has a life cycle of 2 years, it is highly unlikely you will ever be able to grow waist-length hair.
9. Hair Count
The average human head has 120,000 hairs. And one of the interesting facts about hair is that the number of hairs you have is also related to its color. If you are blonde, you’ll generally have more – around 140,000 but, if you’re a redhead, you’ll probably have around 90,000.
10. Hair Loss
You lose 100 hairs every day. As these fall out they are replaced by new hairs (as explained above). Baldness and thinning occurs because old hairs are dying off but no new hairs are being created. As you age, the rate of hair growth slows and might only be as little as 0.25cm a month (less than one-tenth of an inch). For women, one of the things you should know about your hair is that you are likely to lose about 20 per cent of it between the ages of 40 and 50.
Human hair is incredibly elastic and remarkably, can stretch up to 20/30 per cent of its relaxed length before it will break. It usually is more elastic when wet.
As well as being elastic, another of the facts about your hair is that it is also incredibly strong. To put it into context, a single healthy hair is stronger than a copper wire of the same thickness. Apparently, the combined strength of one head of human hair can support the weight equivalent of 99 average-sized people.
13. Split Ends
This is one of the interesting and misunderstood facts about hair. Split ends is a good description because that is exactly what it looks like – a strand that has split into 2 (or more) threads. The “split” occurs due to damage. This damage is capable of making the strand split the full length of the shaft, but, the damage has usually weakened the strand sufficiently enough to cause it to break. The big misconception about split ends is that they can be repaired. They cannot. The only cure for split ends is to cut the strand ahead of the split. Shampoos and conditioners which claim to “fix” split ends effectively “glue” the broken strands back together and it is a temporary repair; eventually the glue effect wears off and the hair strand continues to split.
14. The Anatomy of Hair
Although every hair is made of the same chemical composition, the ways it grows and shapes differs by ethnicity. People of African descent have a flat hair shaft, Asian hair is round, whereas the shaft of a Caucasian head is more of an oval shape.
15. A Question of Color
What would you say is the most common hair color in the world? It’s black! Not surprising considering the percentage of the world’s population that is Asian – and they have black hair. 2 per cent of the world have blonde as their natural color, and the rarest color is red, with only 1 per cent. Scotland bucks this trend. 13 per cent of Scottish people are natural redheads, although the USA has the largest redhead population in numbers.
16. All Change
It is also one of the facts of hair that we like to mess around with its color. Back in 1950, just 7 per cent of the US female population dyed their hair and it was usually to cover grey. Today, a whopping 75 per cent of American women dye their hair.
17. Forensically Speaking
Hair is one of the most common forms of forensic matter. A hair strand provides a picture of what has been going through your body and blood stream including food, drugs and alcohol. But, despite its usefulness, the one vital piece of information a hair cannot provide is gender.
18. Some Biological Facts about Hair
Hair is the fastest growing part/tissue of the human body – only bone marrow generates more quickly.
Hair follicles form when a fetus is about 5 months old and there are some 5 million follicles all over the body.
These follicles can be everywhere and anywhere except the soles of the feet, the palms of the hands, the lips and the mucus membranes.
19. Some Beauty Facts about Hair
By the time you reach the age of 65, as an average woman, you will have spent a total of 7 months fixing your hair. This is based on a weekly time of 1 hour and 53 minutes spent on washing, blow drying and styling.
You spend more than $780 per annum on hair product.
Curling tongs were first used by the Ancient Romans and the Ancient Egyptians were the first to remove unwanted body hair.
20. Some Other Facts about Hair
The Guinness Book of Records shows that the female with the longest hair is Xie Qiuping from China. When measured in May 2004, it was 18 feet and 5.54 inches (5.627 meters) long.
Victorians used to make jewelry from hair – usually as mourning pieces. And, it wasn’t just a small piece of hair kept in a locket – hair was woven into rings, bracelets and brooches.
Some pretty horrible things have been used as hair dye in the past: Ancient Romans used pigeon dung for blonde hair, while Renaissance women used horse urine.
I do hope you’ve enjoyed our little foray into the world of hair, and that it was interesting and entertaining. Like I said at the beginning – you won’t learn everything there is to know about hair, but you know more now! Do you know any other fascinating hair history or facts to share?