CAUSES OF DANDRUFF (2)

Hair combing / brushing

Combing or brushing help to remove shed skin on our scalp. It has been suggested that inadequate combing or brushing lead to buildup of shed skin giving rise to slightly increased risk of dandruff. However, other studies indicated frequent combing and over shampooing could result in development of dandruff. (Indian J Dermatol. 2010). The reason given was that frequent combing and over shampooing affected the integrity and barrier function of the outermost layer of the skin. This made it easier for organisms to establish themselves and adhere to the skin.

Stress

A 2007 study found that 82 percent of patients with depression and anxiety have excessive flaky scalp. Stress lowers our immunity and induces the body to produce chemicals called glucocorticoids, a substance that can calm us down. Glucocorticoids can alter the cell makeup on the scalp, possibly leading us vulnerable to the fungus malassezia ... and the dandruff it is often associated with.

Hormones

The sebaceous glands that produce sebum become very active during puberty due to Hormonal changes. Sebum comprises a mixture of saturated and unsaturated fatty acids that give our skin integrity.

In 2005, scientists from USA and Korea discovered the fungus malassezia like to feed on saturated fatty acids in sebum. After eating up the saturated fats, our scalp is left with too much unsaturated fats. It was thought that excess unsaturated fatty acids together with changed structure of skin tissues due to glucocorticoids make our scalp vulnerable to flaking and dandruff.

Is malassezia the culprit triggering dandruff due to increased oil production induced by hormones? Perhaps not, because etiological studies found the prevalence rate of dandruff almost equal in pubertal and in older age groups. At puberty, hormones induced high oil production in sebaceous glands whereas in older people, hormonal production has tapered off and oil glands are not as active. Yet, malassezia is prevalent in both wet and dry dandruff.

Did the conflicting opinions and evidence leave you scratching your head in bewilderment?

In the next installment let us explore the issues of infection, genetic factor and illness.