Hair and Scalp

Hair can grow on most areas of the human body, except on the palms of the hands and the soles of the feet (among other areas), but hair is most noticeable in most people in a small number of areas, which are also the ones that are most commonly trimmed, plucked, or shaved. These include the face, nose, ears, head, eyebrows, eyelashes, legs and armpits, as well as the pubic region.

Hair can be divided into three parts length-wise, (a) the bulb, a swelling at the hair base which originates from the dermis, (b) the root, which is the hair lying beneath the skin surface, and (c) the shaft, which is the hair above the skin surface. In cross-section, there are also three parts, (a) the medulla, an area in the core which contains loose cells and airspaces (b) the cortex, which contains densely packed keratin and (c) the cuticle, which is a single layer of cells arranged like roof shingles.

Human scalp hair normally grows at a rate of 0.4 mm /day (incidentally human scalp hair grows at a rate four times that of human nails. Human nails grow at a rate of 0.1 mm/day). It is commonly accepted that emotional distress, especially that caused by verbal abuse, etc. often is a contributing factor to a slower hair growth rate.

Dandruff - Due to the excessive shedding of dead skin cells from the scalp. Dandruff can also be caused by frequent exposure to extreme heat and cold. As it is normal for skin cells to die and flake off, a small amount of flaking is normal and in fact quite common. Some people, however, either chronically or as a result of certain triggers, experience an unusually large amount of flaking, which can also be accompanied by redness and irritation.

Hair Texture - Usually defined as fine, medium, coarse, wiry or frizzy hair depending on the hair diameter. Within these four texture ranges hair can also be thin, medium or thick density and it can be straight, curly, 'kinky' (tightly coiled), or wavy. Hair conditioner also affects hair texture. Hair can be healthy, normal, oily, dry, damaged or a combination. Hair texture can also be affected by hair styling equipment such as straighteners, crimpers, or curlers.

Curly and/or 'kinky' hair has a different biological structure from straight hair. It tends to be much drier than straight hair because the oils secreted into the hair shaft by the sebaceous glands can more easily travel down the shaft of straight hair. People with very curly hair may find that this hair type can be dry and often frizzy.

Gray Hair - The tendency of older people to develop gray hair is due to a build up of hydrogen peroxide due to wear and tear of the hair follicles. Gray hair is considered to be a characteristic of normal aging. The age at which this occurs varies from person to person, but in general nearly everyone 75 years or older has gray hair, and in general men tend to become gray at younger ages than women. Red hair usually doesn't turn gray with age; rather it becomes a sandy color and afterward turns white.

Hair Loss - Often drugs used in cancer chemotherapy will frequently cause a temporary loss of hair, most noticeable on the head and eyebrows, because they kill all rapidly dividing cells, not just the cancerous ones. Other diseases and traumas can cause temporary or permanent loss of hair, either generally or in patches. Patients with Hyperthyroidism or Hypothyroidism can experience hair loss until their hormone levels are regulated.

Baldness - Involves the state of lacking hair where it often grows, especially on the head. The most common form of baldness is a progressive hair thinning condition called androgenic alopecia. The amount and patterns of baldness can vary greatly; it ranges from male and female pattern alopecia (androgenic alopecia, also called androgenetic alopecia or alopecia androgenetica), alopecia areata, which involves the loss of some of the hair from the head, and alopecia totalis, which involves the loss of all head hair, to the most extreme form, alopecia universalis, which involves the loss of all hair from the head and the body.

Treatments for various forms of alopecia have limited success. Some hair loss sufferers make use of clinically proven treatments such as finasteride and topically applied minoxidil in an attempt to prevent further loss and regrow hair. As a general rule, it is easier to maintain remaining hair than it is to regrow; however, the treatments mentioned may prevent hair loss from Androgenetic alopecia, and there are new technologies in cosmetic transplant surgery and hair replacement systems that can be completely undetectable.

In the USA, there are only two drug-based treatments that have been approved by the U.S. Food and Drug Administration (FDA) and one product that has been cleared by the FDA for the treatment of androgenetic alopecia, they are finasteride (marketed for hair loss as Propecia) and minoxidil.

Further Information Regarding Hair and Scalp

Stress Can Make Your Hair Turn Gray
Those pesky graying hairs that tend to crop up with age really are signs of stress, reveals a new report in the June 12 issue of Cell, a Cell Press publication.

How to Control and Get Rid of Head Lice
In this article I am going to discuss why people get head lice and what to do and what not to do to get rid head lice. I will show the best treatments available to get rid of head lice in days based on my personal knowledge and years of research after my two young ones couldn't get rid of their head lice after picking it up at school.

Great Hair Days - Tips for Keeping Hair Under Control
A Collection of hints and hair care tips for getting your hair under control and achieving great hair days. If you want to have that "just out of the hair salon" look then update yourself about the commandments of hair control.

Dry and Brittle Hair Care Tips
The sun and humidity is the worst enemy of your hair's cuticles, causing damage that results in split ends, dry hair, frizzy hair or brittle hair. In healthy conditions, hair’s moisture content is approximately 10%, but sunlight has the same damaging effect as a hot blow dryer on your hair.

Frizzy Hair Care Maintenance Tips
Frizzy hair doesn't discriminate. It plagues both the thin and thick haired alike. If your hair has even the slightest wave or curl, it's susceptible to frizz.

What Causes Gray Hair?
At some stage in our lives, both men and women will experience the on set of gray Hair. Contrary to popular belief graying hair is not always related to ones age. Gray hair can occur as young as in our teens and range into our late 50's and even older.

Hair Care Myths and Tips
Hair is an outgrowth of protein,found only on mammals. It projects from the epidermis, though it grows from hair follicles deep in the dermis. The average human head has about 100,000 hair follicles.