– BEAUTIFUL BODY –
This week, Tidbits combs up some facts on our crowning glory – hair!
• The average person has between 100,000 and 150,000 strands of hair on his/her head. That number varies depending on hair color. Natural blonds have the most hair, about 150,000 strands, while brunettes have 100,000, with just 90,000 for redheads. The head has about 800 to 1,300 hairs per square inch, each with a thickness between .016 and .05 mm.
• Hair color is determined by genetics and differs by ethnicity. Black or brown hair comprises about 90% of people in the world. Asian hair is almost always black or dark brown and straight. It also grows the fastest and has the best elasticity, while African hair grows slower and is more fragile.
• Every strand of hair contains proteins, lipids, water, pigments, and traces of 14 different elements. It’s made up of 50.65% carbon, 20.85% oxygen, 17.14% nitrogen, 6.36% hydrogen, and 5% sulfur. There are trace amounts of magnesium, arsenic, iron, chromium, and even gold!
• A hair has two parts, the follicle and the shaft. The follicle is the part below the skin where it begins to grow, starting in the epidermis, the skin’s top layer. The shaft is what you see above the skin. Once the hair grows beyond the skin, the cells are no longer alive.
• Over the course of your lifetime, you will grow 590 miles (949 km) worth of hair. On any day, 90% of your hair is growing, while the other 10% is resting. Hair is one of the body’s fastest-growing tissue, growing .3 to .5 mm a day (0.012 to 0.02 inches), about 15 cm or 6 inches a year (only bone marrow grows faster than hair). Hair grows faster during the summer and when you’re asleep. Those between the ages of 16 and 24 have the fastest-growing hair.
• A hair’s lifespan is anywhere between 4 and 7 years. Everybody loses between 40 and 150 hairs every day, but because new hairs are constantly growing and replacing the lost ones, this loss isn’t noticeable. Alopecia is a condition that causes hair loss in patches, caused by the immune system attacking hair follicles. However, other things can cause temporary hair loss, such as crash dieting, thyroid imbalance, an iron deficiency, hormones from childbirth, and reactions to medication.
• The middle layer of the strand, the cortex, is made up of long proteins twisted together. It’s here that melanin lives, the pigment cells responsible for hair color. Once a follicle stops producing melanin, hair will turn gray, and it can never be naturally colored again.
• When the ends of hair become dry, brittle, damaged, and frayed, the result is split ends. There’s actually a scientific germ for split ends – trichoptilosis. Although some products claim to repair split ends, the only sure way to get rid of them is to cut them.
• Why do some people have curly hair and some have straight? Hair with a circular circumference produces straight hair, while hair that is more flat than round determines curly hair.
• Less than 2% of the world’s population has naturally red hair, but the percentage of redheads in Ireland, which has the highest number of redheads per capita, is around 10%.
• In the 1950s, only about 5% of women dyed their hair. Today, that figure is 75%! Women in ancient Rome dyed their hair with pigeon droppings or decomposed leeches that had rotted in red wine for 40 days. Gray hair was covered with a concoction of ashes, boiled walnut shells, and earthworms. Surely there must have been an easier way!