Overview
Dandruff is a condition characterized by itchy and flaking skin on the scalp and face. According to the Mayo Clinic, dandruff is common and chronic, but it is not contagious and is rarely serious.
Identification
Dandruff flakes may be small and dry, or large and clumped because of excess skin oils. The white to light-yellow flakes may appear on the hair, scalp or shoulders and may be most noticeable on dark clothing. The condition tends to improve with more frequent shampooing and during the summer months, notes the American Osteopathic College of Dermatology.
Skin Cells
Your body continuously replaces skin cells, pushing healthy and strong cells from the deeper dermis to the outermost layer of the skin, known as the epidermis. According to the Nemours Foundation, this trip typically takes between two to four weeks, although each minute of each day between 30,000 and 40,000 skin cells are lost from the top layer. When skin regeneration is overly fast, the shedding becomes noticeable.
Causes
Scalp dandruff may be related to the presence of a yeast that eats the oil-like sebum produced by the hair follicles. A healthy head of hair has enough sebum to lubricate the scalp and hair follicles and the hair has elasticity and shine. When the yeast becomes overactive, the skin becomes dry and irritated, leading to skin cell loss. The skin then overproduces healthy skin cells to compensate, leading to more cell shedding.
Yeast production may increase because of many factors, including hormonal changes, an increase in stress level, a compromised immune system, allergies or underlying skin conditions, says the Mayo Clinic. Individuals on prescription medications for skin diseases may develop skin sensitivities, which can further exacerbate the problem.
Risk Factors
Although dandruff can occur at any age, it most commonly begins in young adulthood and lasts through middle age, notes the Mayo Clinic. Men are more prone to having dandruff, as they have larger sebaceous glands on the scalp. Individuals with neurological conditions including Parkinson’s disease and stroke may be prone to developing dandruff, states the National Institutes of Health.
Treatment
Medicated shampoos with ingredients such as selenium sulfide and zinc pyrithione are formulated to control dandruff. By washing with warm water and using cooler air settings on a hair dryer, you can reduce heat-related stress on the scalp. Using fewer hair-care products and switching shampoos can minimize product buildup on the scalp that might irritate the skin and lead to flaking. The website Health911.com suggests limiting foods that contain sugar and yeast and warns that individuals on low- or no-fat diets may need to take fatty-acid supplements to improve elasticity and moisture of the skin and reduce dandruff flakes.