What causes dandruff?
Let’s start with what dandruff actually is. Head shedding is a chronic skin condition caused by the buildup of yeast around the base of your hair follicles, says Dr. Nicole Rogers, M.D., a professor of dermatology at Tulane University School of Medicine.
Yeast? So my head has a yeast infection? Like women get in their hoo-haas?
It’s not the same thing at all. Totally different fungus. The one on your scalp is caused by a yeast-like fungus called Malassezia globosa.
“The fungus feeds off the skin’s sebum and excretes end products onto the scalp which can irritate the scalp skin, resulting in dandruff and its symptoms like dryness, itch, and flaking,” says Dr. Rolanda J. Wilkerson, Ph.D., a principal scientist for Procter and Gamble. (That fungus is just one of The Gross Things Hanging Out On Your Head.)
Can dandruff be cured?
No, but it can be controlled. You’ll need to reserve a permanent space in your shower for specialized treatment shampoo containing zinc pyrithione or selenium sulfide. These anti-dandruff ingredients can help slow the rate at which your skin cells die and slough off.
When used daily and left in for at least five minutes, these shampoo treatments can rid a good portion of white flakes in about a month, says Dr. Rogers.
So I’ll be cured, right? If I can get the dandruff to stop, I’m cured.
Slow down, Tex. Assuming you have any flare-ups under control, you can switch back to regular shampoo as long as you continue to rotate in dandruff-control stuff at least once or twice a week, says Marie Jhin, M.D., a San Francisco dermatologist.
One caution: Whichever shampoo you use, Dr. Jhin recommends always rinsing thoroughly. Any leftover residue on your head could create a feeding ground for yeast and lead to a wicked scalp storm.
(Speaking of body hair that just makes our lives more difficult, have you ever wondered Should Men Shave Their Legs? We asked our readers and got some surprising opinions.)
Am I overwashing? Maybe I’m shampooing my hair too much. Could that be making it worse?
Most dermatological conditions are aggravated by excessive hair washing, but not dandruff. “This is the one thing that gets better with washing,” says Dr. Ilyse Lefkowicz, M.D., a New York-based dermatologist and clinical instructor in the Department of Dermatology at Mount Sinai Medical Center.
It’s not that dandruff makes your hair and scalp dirty. The fungus that resides on our scalps feeds off sebum—wash effectively and you’ll reduce the sebum, cutting off the food supply.
What does “wash effectively” mean? If I have dandruff, should I be washing it a different way?
Your dandruff shampoo isn’t just made for your hair. The real work its doing is on your scalp, so you need to get the shampoo directly on the scalp and clean the skin there. “Finger contact with scalp is important,” says Dr. Lefkowicz, who suggests a gentle massage.
It doesn’t take long, either. “As long as it makes contact with your scalp, the technology will sink in,” she says.
Also, only use lukewarm water. Heat can irritate the scalp and encourages inflammation. “When you use very hot water, you are affecting the skin moisture barrier,” says Lefkowicz.
Are there environmental factors that could be causing my dandruff? Like if the temperature gets suddenly really hot or cold?
Where are you getting this stuff?
Hey, the internet says a lot of things.
“Extreme weather does not cause dandruff.,” says Wilkerson. “However, environmental changes can aggravate a dandruff skin condition in those who are already dandruff sufferers.” So yeah, if you’ve got dandruff and you go from a warm climate to a really cold one, it might make your dandruff worse. But the weather is not giving you dandruff.
So what the hell is then?!
It’s funny you should put it that way, with the unnecessary expletive and exclamation mark. A big factor in dandruff is actually stress.
What?! You have got to be freaking kidding me!
How ironic. You’re getting stressed out right now about dandruff, and that’s giving you dandruff.
Oh for the love of…!
It’s a vicious cycle, we know. Dr. Lefkowicz says that when she meets with patients who have especially aggressive dandruff, “My first question is ‘What’s going on?’ Is there a stressful event that’s triggering this reaction?” Any time your immune system is altered, it can provoke dandruff flare-ups.
So you’re saying calm down?
Yes. Use your dandruff shampoo, use it correctly, and consult these 52 Ways to Control and Conquer Stress. You’ll be fine.