Dandruff

Dandruff Symptom and Problem 
  A person's entire body surface continuously sheds dead skin cells. The skin itself sheds every twenty-four days. Dandruff, the shedding of dead skin cells from the scalp at an excessive rate, is the result of the normal growing process of the skin cells of the scalp.  Dandruff is a bothersome problem sometimes thought to be associated with inefficient hair care. Nothing could be further from the truth - anyone who has dandruff knows that!  If you're troubled by dandruff, that snowy, dust-like stuff that falls from scalp to shoulders, you're not alone: Nearly everyone has dandruff to some degree. But care must be taken not to confuse simple dandruff with other conditions that also cause flaking of the scalp, such as seborrheic dermatitisor psoriasis.  Dandruff occurs when the scalp sheds dead epidermal (skin) cells in large clumps. Dandruff scales appear dry, white or grayish, appearing as small, unsightly patches, especially on top of the head.  Scalp cells replenish themselves in a pattern similar to that of hair, but more rapidly: The skin of the head renews itself about once a month. Dead scalp cells are constantly being pushed from the deepest layer of the epidermis to the skin's surface, where they gradually die. Usually the scalp sheds them in a nearly invisible way. But for reasons that are still unclear, cell turnover sometimes becomes unusually rapid, and dead cells are shed as the visible flakes called dandruff. Although most people assume dandruff comes from a dry scalp, the opposite is true: People with oily scalps tend to suffer most from dandruff.  "This may be due to an oily scalp supporting the growth of yeast in the scalp, which is thought to be instrumental in the development of scaling and scalp irritation," says Joseph P. Bark, M.D., chairman of dermatology at St. Joseph's Hospital in Lexington, Ky. "A large preponderance of males have dandruff, which may suggest some role of androgen hormones in dandruff."  Bark says that dandruff has its bright side: If the scalp doesn't shed its dead skin cells, the human scalp would be tremendously thick. "But when the cell turnover goes too far and increases, then you get not only visible excess scaling, but redness and itching," he says. "Redness and itching is actually seborrheic dermatitis, and it frequently occurs around the folds of the nose and the eyebrow areas, not just the scalp."  Sometimes itching of the scalp is also experienced. Dandruff is a very common problem. The most common cause is probably a small skin fungus, previously known as Pityrosporum ovale, now renamed Malassezia furfur. The fungus is found naturally on the skin surface of both healthy people and those with dandruff. The fungus likes fat, and is consequently found most on skin areas with plenty of sebaceous glands: on the scalp, face and upper part of the body. When Malassezia furfur grows too rapidly, the natural renewal of cells is disturbed and dandruff appears with itching.  Dandruff is made up of bits of dead skin that peel away from the scalp as a result of the effects of metabolism. Normally, dandruff, in its early stages of growth, is not visible to the naked eye. It becomes visible only after enlarging into pieces of dead skin (what we normally call "dandruff") as a result of the propagation of bacteria and/or problems with seborrhoeic scalp conditions. Persons suffering from prolonged dandruff are said to have a dandruff ailment. This type of ailment, accompanied by itchiness, can lead to eczema if it worsens.