One of the most common dermatological MYTHS is the belief that flaky, itchy scalp, so-called dandruff, comes from washing your hair too much. The truth is the exact opposite. Read on.
Almost 100% of patients who see me as a dermatologist for dandruff suspect the flakes and itch are from drying out of their scalp. Patients instinctively reduce their hair washing but it doesn’t help. In fact, they all admit their scalp feels better the day of and day after washing, but gets worse after two or three days of NOT washing. Here’s the explanation:
Dandruff affects almost half the world population of adolescents and young adults to some degree. It affects both men and women but seems to be more common in men. Flakiness, itch, and oily scalp are the most common signs. At its worst, dandruff goes by a different name—seborrheic dermatitis and can even involve the skin of the face.
Many factors contribute: Testosterone leads to oiliness (both men and women have testosterone). Oiliness promotes microscopic yeast organisms called Malassezia. Individual immune responses lead to the inflammation (redness, itch) and discomfort. That, basically, is the package.
So how does washing hair influence the problem? The issue is this: Washing removes the flakes, the oil and the yeast which in turn reduces immune reactions which ultimately reduces flakiness, itchiness and redness. The purpose is to clean your scalp, not your hair per se (the hair will get clean in the process). Use conditioners as needed.
What shampoo to use?Mere washing with plain shampoo can help, but the best anti-dandruff shampoos contain either coal tar (T-Gel®, Pentrax®), anti-fungal chemicals (Nizoral®, Cicloprox®) or cortisone-like steroids (Clobex®). Personally, I favor tar shampoos, which also happen to be the least expensive.
How often should you wash your hair? In general, the more you wash your hair, the better your scalp will feel. (Scalp skin is similar to face skin, and you don’t wash your face only once per week!) Daily hair washing is usually adequate in the setting of dandruff/seborrheic dermatitis. It depends on the severity of the condition. The important fact is that washing does not worsen the problem, it only helps.
There are cases where seeing a doctor is required. Topical prescription lotions can reduce inflammation or reduce the Malassezia yeast. Fortunately, the condition is not dangerous to your health, and tends to improve as you move from the prime of life into middle age and beyond. Something to look forward to!
And ONE MORE THING: The concept of lather, rinse, repeat is complete nonsense, falsely made up by manufacturers so that you use up twice as much product as you need. Once is perfectly adequate. Thank you.