Hair Physiology Myths

Actually, there's no association between dandruff and MPB. Dandruff is not a cause of hair loss. Dandruff is a chronic, non-inflammatory scalp condition that results in excessive scaling of the scalp epidermis (the most superficial of the skin layers) and is clinically visible in approximately 20% of the population. The severity of dandruff declines in the summer and, despite popular misconceptions is not proved to be aggravated by emotional stress.

Although it is normal for epidermal cells on the scalp to continually slough off (just as they do elsewhere on the body), in patients with dandruff the turnover rate of epidermal cells on the scalp is about twice that of those on the normal scalp. Dandruff scales often appear around a hair shaft because of the epithelial growth at the base of the hair, but there is no association with hair loss.

Routine washing with a non-prescription shampoo is usually sufficient to control dandruff. The active ingredients in dandruff shampoos include selenium, coal tar, salicylic acid, ketoconazole, pyrithium zinc, etc. Use whichever product works most effectively for you.

True, but you don't always see the bulb. The collection of dead cells and debris at the scalp end of a hair that has spontaneously shed is extremely friable and is easily abraded off.

No such luck. The length to which the hair on your scalp will grow depends on your hair's natural cycle, which is unique to you. The longer the hair's growth phase (anagen), the longer the hair will grow. The length of the anagen phase of terminal scalp hair is generally in the range of 3 to 5 years. If you have a naturally long growth phase, you can grow your hair to well below your waist. Whereas, if you have a naturally shorter growth phase, your hair will shed before it grows to that length. The length of your particular growth phase is strictly based on heredity. The rate at which hair on the scalp will grow is 1/2 inch (1 cm)/month.

Wrong. Shaving the head has no effect on either hair growth or hair loss. The common misperception that shaving enhances growth is probably due to the appearance of all of the hair shafts from anagen follicles re-emerging at the same time. So, it looks optimistically like a synchronized, enhanced period of growth. But it's an illusion. Hair on the scalp grows approximately one-half inch (1 cm) per month and there's nothing we can do to change that. Take note that men may shave their beards daily. If shaving enhanced growth, it would become impossible to shave after months of repeated shaving.