Like other parts of our health, we often take our hair growth for granted. It just kind of does its thing: just keeps growing. We can wash it, blow-dry it, curl it, dye it, and no matter how much physical damage we do to it, it’s ok; because it’ll just grow back. We often associate hair loss with men or aging in general. But anyone of any age can lose considerable amounts of hair simply from poor nutrition.

How a Hair is Made

The actual hair is composed of four parts: bulb, follicle, root, and shaft. The hair bulb lies furthest in the scalp, right next to a group of capillaries (called the dermal papilla) which deliver blood – and therefore nutrients – to the growing bulb. The live cells of the hair bulb divide and divide, growing up into the hair follicle and hair root. As these cells move further up the hair they mature through the process of keratinization, where they lose their nucleus, fill with fibrous protein, and are no longer considered alive.

By the time these keratinized cells become part of the hair shaft (the part outside of the scalp), they are simply fibers made of keratinized protein. The hair shaft is composed of three layers: the outer cuticle, the middle cortex, and the inner medulla. All of these parts are composed of protein. In fact, the actual hair shaft is about 91% protein.

The Hair Growth Cycle

A hair forms, grows, and falls out naturally in a series of three stages:

• Anagen Phase: For two to six years a hair is in this stage, growing at a rate of about 10 cm per year. About 85% of hairs are in this phase at any one time.

• Catagen Phase: This phase lasts about 1 to 2 weeks and is considered a transitional stage, where the hair bulb slowly detaches from the dermal papilla and shrinks to about 1/6 of its normal size.

• Telogen Phase: After the catagen phase, hairs enter a resting state called telogen. They will stay in this stage for about 5 or 6 weeks, remaining attached to the scalp until they falls out naturally or are pushed our by a new hair shafts.

How Poor Nutrition Affects Hair Growth

Hairs need lots of protein, vitamins, and minerals to grow. Therefore, diets deficient in these nutrients can cause hair growth to stop until consumption returns to healthy levels. Protein deficiency, especially, can affect hair growth since protein is needed in all parts of the body, many more vital to survival than hair growth. When protein intake is greatly decreased, due to poorly balanced vegetarian or crash diets, the body instructs growing hairs to enter the telogen phase. These hairs will then fall out the usual 5 to 6 weeks later.

Getting the Nutrients Necessary for Hair Growth

Because protein is so vital to hair growth, it’s important to get plenty of it in your diet. You can kill two birds with one stone by eating meats rich in B-vitamins (also important for hair growth) like fish and poultry. If your diet prohibits meat, be sure to make up for the protein lost by eating things like beans and nuts.

Nutrients such as vitamin A, vitamin B6 (also called biotin), and zinc are also necessary for healthy hair growth. If you don’t get enough of these nutrients from your diet try taking a nutritional supplement.

Find a good source of biotin for hair loss here.

Sources:
http://www.follicle.com/hair-structure-life-cycle.html
http://www.hairfinder.com/hairquestions/hairgrowth.htm
http://www.dentalplans.com/Dental-Health-Articles/Diet-and-Hair-Loss.asp
http://blog.worldvillage.com/health/zinc_for_hair_loss.html
http://www.healthscout.com/ency/68/429/main.html