The bad news: the causes are unknown. The good news: treatment ‎options are available.‎

One of the biggest annoyances known to man is dandruff; white flakes falling from one’s head and landing gently on the forehead and shoulders. But not to worry, these are just dead skin cells coming off the scalp.

The turnover of skin cells is merely routine - older cells are pushed to the surface of the skin, eventually dying and flaking off. Normally, the turnover of skin cells is not visible and the cells that are broken down are washed away with a good shampoo. But in some situations the turnover rate is abnormally fast, and dead cells that accumulate on the hair look like scales. Dandruff can also occur due to skin diseases such as psoriasis and eczema, or yeast that regularly populate our scalp, but the “normal” reasons for the formation of dandruff remain unknown till this day.

The scalp is a breeding ground for many species of bacteria and fungi, including Malassezia yeast. This fungus feeds on fats and is found primarily around the sebaceous glands in the skin, as they are a good source of fat. Studies have shown that people suffering from dandruff have an increased incidence and quantity of Malassezia, and antifungal treatment can help get rid of the dandruff. Nevertheless, it remains unclear what is the initial cause - if the dandruff is a convenient platform for the development of the fungus, or the fungus causes dandruff. However, a dedicated treatment targeting the Malassezia fungus often solves the problem of dandruff.

There are also other hypotheses for the cause of the formation of dandruff, unrelated to the world of bacteria and fungi; prolonged sun exposure, washing hair too often, sensitivity to certain cosmetics, excessive combing, mental stress and increased hormonal activity - these are just some on the list, but there is an insufficient amount of scientific evidence to make a definite connection to dandruff.

Looking for solutions

Dandruff treatment depends on the severity of the situation. Ordinarily it is possible to use an anti-dandruff shampoo containing anti-fungal substances. Although the relationship between the presence of fungi and the appearance of dandruff is not entirely understood, these agents are generally useful.

Other preparations that reduce the formation of dandruff are based on substances such as tar, sulfur, zinc and salicylic acid. Zinc helps in balancing the turnover rate of skin cells and the secretion of fatty acids from the sebaceous glands. A few studies have shown that after zinc treatment, the concentration of fungi on the scalp significantly decreases.

Salicylic acid and sulfur help break down the bonds between dead skin cells, so they are washed away more easily. Using tar is useful in the treatment of skin diseases such as psoriasis and dandruff, but it has been difficult to pinpoint the exact mechanism responsible, since tar has a large number of active ingredients.

There are also more serious medical conditions that can accompany dandruff. One of them is seborrheic dermatitis; a chronic inflammation of the sebaceous glands in the skin, characterized by a rash, itching, redness and the appearance of dandruff. Treatment for this disease includes the use of steroids that inhibit the activity of the immune system and reduce the inflammatory response.