Hair Terminology

Hair is mostly composed of protein known as keratin. Keratin is found in the horny growths including skin as well as nails. Today we know that the chemical composition of hair can vary depending on its color. For example darker hair has more carbon and less oxygen. The average hair is composed of 50.65% carbon, , 20.85% oxygen, 17.14% nitrogen, 6.36% hydrogen, 5% sulfur.

Almost a soft downy this hair is found on the forehead on the cheeks and nearly all other areas on the body. It helps the body efficiently evaporate perspiration.

Is the part of the hair structure located beneath the skin’s surface. This portion of the hair is enclosed within the hair follicle.

Is the part of the hair structure that extends above the skin’s surface.

Is the tube like depression in the scalp that encases the hair root. The follicle sets at an angle it does not run straight down. The hair flows naturally to one side.

Growing and shedding are normal patterns of hair cycles. Each follicle cycles through  3 stages many times throughout its life.

The average growth of hair on the scalp is about an inch every 2 months. 90% of the hair could be growing at any one time. This phase can last from 2 to 6 years, during which the hair-shaft diameter increases in size and the hair reaches its maximum length. In different areas of the body the rate of hair growth can differ between sexes, and ages. Nutrition, health, age, hormones, and stress are influencing factors in hair growth.

The end of the growth phase is signaled by the transitional phase. It is very short, lasting one to two weeks. The follicle begins to rapidly decrease in volume while its lower part of the follicle loosens.

As Catagen ends the hair follicle begins a two to six month phase of rest. During this time the follicle is shorter, approximately one half to a third of the length.