1. Dandruff (Seborrhea) Slideshow Pictures
2. What Your Scalp and Hair Say About Your Health
3. Top 10 Foods for Healthy Hair Slideshow Pictures

Medical Author:

Nili N. Alai, MD, FAAD

Nili N. Alai, MD, FAAD

Dr. Alai is an actively practicing medical and surgical dermatologist in south Orange County, California. She has been a professor of dermatology and family medicine at the University of California, Irvine since 2000. She is U.S. board-certified in dermatology, a 10-year-certified fellow of the American Academy of Dermatology, and Fellow of the American Society of Mohs Surgery.

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Medical Editor:

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, Chief Medical Editor

Melissa Conrad Stöppler, MD, is a U.S. board-certified Anatomic Pathologist with subspecialty training in the fields of Experimental and Molecular Pathology. Dr. Stöppler's educational background includes a BA with Highest Distinction from the University of Virginia and an MD from the University of North Carolina. She completed residency training in Anatomic Pathology at Georgetown University followed by subspecialty fellowship training in molecular diagnostics and experimental pathology.

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The exact cause of dandruff is unknown. Possible causes and associations include increased oil production, oily skin, increased skin secretions, and increased numbers of normal skin yeasts.

Bacteria have not been found to cause dandruff. Dandruff is not a fungal infection and is not the same as scalp "ringworm," which is actually a fungal infection called tinea capitis. Dandruff is not contagious.

Dandruff may also be triggered or made worse by poor hygiene and infrequent shampooing and washing. The immune system may also play a part in dandruff. Although mild dandruff is a very common condition in many people with a normal immune system, severe dandruff is generally more common in people with chronic illnesses such as Parkinson' s disease or a compromised immune system as in advanced HIV/AIDS.

• Common triggers (factors that may worsen) of dandruff include the following:



• Increased oil production



• Oily skin



• Oily scalp



• Sweating



• Poor hygiene



• Weather (hot and humid or cold and dry)



• Infrequent washing or shampooing



• Concurrent yeast or fungal
skin infections or overgrowths


• Poor immune system



• Chronic illness



• Emotional or mental stress

• Risk factors for dandruff include the following:



• People with extreme or severe cases of dandruff usually also have other chronic health conditions



• Dandruff probably has a small hereditary component making it more common to run in families.