Seborrheic dermatitis is a common papulosquamous disorder of the skin, affecting 3% to 5% of the population. Dandruff, a less severe form of seborrheic dermatitis, affects a greater proportion of the population.

Dandruff is the most common condition affecting the scalp. Skin is constantly renewing itself and dead cells from the scalp fall off as new cells form beneath them. Everyone loses skin cells in this way, but with dandruff the whole process is faster, so a greater number of cells are shed. The cells are also shed in clumps that are big enough to be seen by the eye as dandruff flakes, particularly when they land on dark clothing. The scalp can also be itchy. The medical name for this condition is pityriasis capitis.

Natural therapy
Although research is still needed to know whether these suggestions help, you may consider eating a healthy diet with more fish and vegetables and less sugar and white bread. See diet for a list of healthy foods to eat. Fish oil supplements should be considered.

Natural dandruff treatment shampoo
Dandruff occurs when flakes of skin develop on the scalp or inside the ear. Active ingredients in over the counter shampoos include salicylic acid, coal tar, zinc, resorcin, ketoconazole or selenium. Consider the use of tea tree oil as a dandruff shampoo.

Treatment of dandruff with 5% tea tree oil shampoo.
J Am Acad Dermatol. 2002.
Dandruff appears to be related to the yeast Pityrosporum ovale. Tea tree oil has antifungal properties with activity against P ovale and may be useful in the treatment of dandruff. We conducted a randomized, single-blind, parallel-group study to investigate the efficacy and tolerability of 5% tea tree oil and placebo in patients with mild to moderate dandruff. One hundred twenty-six male and female patients, aged 14 years and older, were randomly assigned to receive either 5% tea tree oil shampoo or placebo, which was used daily for 4 weeks. The dandruff was scored on a quadrant-area-severity scale and by patient self-assessment scores of scaliness, itchiness, and greasiness. The 5% tea tree oil shampoo group showed a 41% improvement in the quadrant-area-severity score compared with 11% in the placebo group. Statistically significant improvements were also observed in the total area of involvement score, the total severity score, and the itchiness and greasiness components of the patients' self-assessments. The scaliness component of patient self-assessment improved but was not statistically significant. There were no adverse effects. Five percent tea tree oil appears to effective and well tolerated in the treatment of dandruff.

Dandruff cause
The flaking occurs due to the increased turnover of skin cells. Dandruff is believed to be associated with an overgrowth of a fungus commonly found on the skin and scalp, called Pityrosporum ovale.
   The use of cheap hair care products that dry or irritate the scalp as well as chemical and mechanical over styling - especially conditioners, may aggravate the condition. Dry environments lead to dryness of the scalp. Consider humidifying your living space if you have dry skin elsewhere on your body. Stress and lack of sleep could be a factor.

Malassezia globosa, a fungus that grows on the skin of between 50 percent and 90 percent of the population causes dandruff and a range of other skin conditions.
   Dandruff is also known as seborrheic dermatitis. Dandruff is an itchy, annoying and persistent skin disorder of the scalp. There are many theories about what actually causes dandruff and a variety of treatments to control it. Possible dandruff causes include hormonal imbalance, excessive perspiration, excessive consumption of sugar, fat, or starch, emotional stress, lack of rest, heredity pre-disposition, poor hygiene, and perhaps allergy or junk food diet.
   Dandruff can happen at any age (called cradle cap in newborns and infants) but is most commonly found in people above the age of 12. Dandruff can run in families and may be triggered by stress, fatigue, oily skin, acne or using hair or skin products that contain alcohol.