In my last column, we focused on some fascinating facts about two extremely complex and critical organs: our heart and our brain. Today, let’s address some fascinating facts about our hair and our nails. Our hair is not alive – the part that is visible, the hair shaft, is actually a strand of protein, produced by a hair follicle. The hair shaft exhibits no biochemical activity, and so is not living.
•On what part of our body does hair grow the fastest? For men, it’s facial hair. If the average man never shaved, his beard could grow to over 30 feet.
•A woman’s hair is typically about half the diameter of a man’s.
•Our hair color determines how many hairs we have. Blondes have about 140,000 follicles on the head; those with black hair have about 110,000, and those with brown hair have about 100,000. Redheads have the least dense hair, with about 90,000 follicles. Each of these follicles is capable of producing 20 individual hairs during a lifetime.
• Do you worry about hair loss? The average person loses 60 to 100 strands of hair per day, so be aware that some hair loss is routine and the hairs will be replaced. A human hair will last for about three to seven years. As long as the hair is not subjected to trauma, it will see quite a few haircuts and styles before falling out. Even when it does fall out and isn’t replaced, we can lose over 50% of our scalp hairs before it becomes very noticeable.
•Who has more hairs per square inch on their body, humans or chimpanzees? The answer: it’s about the same! How can that be, since a chimpanzee is covered in hair? Well, we humans are, as well. Our body hair is just not as obvious, since the hairs may be too fine or light to be easily seen.
•Our hair is surprisingly durable. It isn’t destroyed by cold weather, change of climate, water, or heat. It tolerates many kinds of acids and corrosive chemicals found in hair products. It is, however, flammable.
Our fingernails and toenails are made up of the same material as is our hair. Our nails are another non-living body part that nonetheless gets a tremendous amount of attention.
•The nail on the middle finger grows the fastest, particularly on the dominant hand. Nails grow faster on longer fingers, and slower on shorter fingers, so it makes sense that the thumbnail is the slowest growing of all.
•Fingernails grow four times faster than toenails, possibly because fingers have more exposure and are used more frequently. The rate of growth is about 1/10 of an inch per month. Nails tend to grow faster during the daytime, and faster during the summer months.
•Men’s nails grow faster than do women’s nails.
•Nails appear to grow after death! What actually happens is that the skin dries out and retracts, exposing more of the nail.
We can easily agree that our hair and nails play a far less important role than do our heart and our brain. Given that, consider how much effort and money both genders put into keeping their hair healthy, clean, present in the proper places, and absent from the others. Look at the proliferation of nail salons for an indication of the time and funds dedicated to nail care. Just imagine how well off we would be if we dedicated all that time to our cardiovascular health and to keeping our brains well exercised!
Dr. Alan Frischer is former chief of staff and former chief of medicine at Downey Regional Medical Center. Write to him in care of this newspaper at 8301 E. Florence Ave., Suite 100, Downey, CA 90240.
Published: Aug. 14, 2014 - Volume 13 - Issue 18