By Dr. Mercola
By the age of 20, about 50 percent of the population worldwide, and 20 percent of Americans have suffered from dandruff, which is an excess of dead skin that dots your hair and shoulders, along with a potentially itchy, scaly scalp. Dandruff may also be accompanied by redness and irritation.
A small amount of flaking is normal, as skin cells do die and flake off your scalp, but some people experience an unusually large amount of flaking, either chronically or as a result of certain triggers.
What Causes Dandruff?
Dry skin is one of the most common causes of dandruff, and if this is the case for you you'll probably notice dry skin elsewhere on your body as well. Dandruff caused by dry skin tends to involve smaller, less oily flakes than dandruff by other causes.1
Dry, flaky skin anywhere on your body is often a sign of a deficiency in animal-based omega-3 fats.
So consuming more omega-3s, in the form of sardines, anchovies, wild-caught Alaskan salmon, or krill oil, would be the first place to start if you have dandruff. Omega-3 fats help normalize your skin fats and prevent dehydration in your cells.
This keeps your skin cells strong and full of moisture, which can help to decrease flakiness. Additionally, omega-3 fats may have an anti-inflammatory effect that can help to soothe irritated skin, including on your scalp.
If you don't think dry skin is to blame, your dandruff may be caused by a fungal infection, specifically a species called pityriasis capitis. Another yeast-like fungus, malassezia globosa, has also been implicated. The fungi live on your scalp, feeding on skin oils.
The malassezia globosa fungus uses enzymes called lipases to metabolize the oils, creating a byproduct called oleic acid. The acid penetrates your skin and triggers skin cell shedding. Des Tobin, professor of Cell Biology at the University of Bradford, told the Daily Mail:2
"This yeast is strongly implicated in dandruff, though the nature of this relationship between the two isn't completely clear… It may introduce an inflammatory immune response in some people because the yeast produces enzymes capable of causing the scalp's surface cells to increase their shedding rate."
Getting to the Underlying Causes of Dandruff…
Sugar will increase the growth of fungus and yeast, and processed grains also break down to sugar very rapidly.
Even juices or consuming lots of fruit can perpetuate the growth of the fungus. So switching to a low-sugar, no-, or low-grain diet will be an important strategy to fight this underlying cause of dandruff. What else might cause dandruff?3
- Seborrheic Dermatitis: This condition, characterized by irritated, oily skin, is another common dandruff cause. You'll typically have red, greasy skin covered with flaky white or yellow scales. The condition may affect not only your scalp but also your eyebrows, breastbone, groin area, armpits, nose, and backs of your ears (all areas rich in oil glands).
- Sensitivities to Hair Products: A sensitivity to hair care products may lead to contact dermatitis, leading to a red, itchy, and scaly scalp. This could be from shampoo, conditioner, or styling products. The chemical paraphenylenediamine, found in permanent hair dyes, is also known to lead to a red, itchy, and scaly scalp.
- Shampooing too Often and Overusing Styling Products: Shampooing your hair too often may irritate your scalp, leading to dandruff. Using too many styling products may cause a similar issue and can build up on your scalp, making it oilier and more prone to dandruff.
Men and People with Neurological Illnesses Are More Likely to Have Dandruff
Anyone can struggle with dandruff at any point during their lives, however men are more likely to have dandruff than women. This may be because the condition is related to male hormones or because men have larger oil-producing glands on their scalps.
Your age may also be a factor. Most cases of dandruff occur between young adulthood and middle age, although it's possible to get it at any age. Dandruff is also more likely to strike in people recovering from an illness, such as a heart attack or stroke, or in those with compromised immune systems (including those with HIV).
People with neurological diseases, such as Parkinson's disease, are also more likely to develop seborrheic dermatitis and dandruff, although the reasons for this are unclear.4
A poor diet may also play a role, specifically if it's lacking in zinc, B vitamins and healthy fats; people with poor intake of these nutrients may be more likely to get dandruff.
Are Medicated Shampoos the Answer?
You may be tempted to opt for a medicated shampoo if dandruff is a problem for you. Some of the most popular brands contain zinc pyrithione, an antifungal that, although effective at controlling dandruff, is not a cure.
If you stop using the shampoo, the dandruff is likely to return, which is why many people end up having to use it at least a few times a week to stay dandruff-free.
Other shampoos contain ketoconazole, another antifungal that may irritate your scalp if you use it more than twice a week. Plus, one study found such shampoos left hair harder to comb, less smooth, and frizzier than the zinc pyrithione shampoo.5
Coal tar is another common ingredient in dandruff shampoos. This works by slowing the growth and die-off of skin cells on your scalp, so there's less flaking. 6 But this is the last thing you want to be rubbing into your scalp, as it's a known carcinogen.
Not to mention, recently fungicides from dandruff shampoos were detected for the first time in water that had already gone through wastewater treatment plants. The fungicides are thought to be killing algae, harming growth in larger plants, and impacting fish and other marine life.7
13 Home Remedies for Dandruff
If you want to make a homemade version of dandruff shampoo, try crushing two aspirin tablets and mixing it with your shampoo (in the palm of your hand) just before you wash your hair.
Aspirin contains salicylic acid, which is used in many dandruff shampoos to loosen flakes and make them easier to wash away. Let the mixture sit on your head for a minute or two before rinsing and repeating with regular shampoo.8
However, medicated shampoos, whether store-bought or homemade, are far from your only option. Often, dandruff can be resolved naturally using the simple home remedies that follow:9
1. Tea Tree Oil or Lavender Oil
Tea tree oil has natural antiviral, antibacterial, and antifungal properties that can reduce inflammation and effectively treat infections. One study found using shampoo with 5 percent tea tree oil lead to a 41 percent improvement in the severity of dandruff.10
Lavender oil is also a potent antifungal that is likely to have similar effects. You can try this method by adding a few drops of tea tree oil or lavender oil to your regular shampoo and using as normal.
2. Baking Soda
Grab a handful of baking soda and rub it into your wet hair and scalp vigorously, then rinse. The baking soda will help to reduce fungi and after a few weeks may help your scalp producing natural oils for softer hair.
3. Apple Cider Vinegar
Apple cider vinegar may change the pH of your scalp, making it less favorable for yeast growth. Try mixing a quarter cup of apple cider vinegar with a quarter cup of water in a spray bottle, then spritz it on your scalp. Wrap your head in a towel and let it sit for 15 minutes to one hour before washing as usual. Use the apple cider spray twice a week.
Mouthwash has antifungal properties that may help rid your scalp of yeast. Apply the mouthwash to your hair after shampooing, rinse and then follow up with your conditioner of choice.
5. Coconut Oil
Coconut oil is rich in lauric acid, which is known for being antiviral, antibacterial, and antifungal. Simply massage a few generous tablespoons into your scalp and let it sit for about an hour. Then shampoo normally.
Like apple cider vinegar, lemon may change the pH of your scalp so dandruff is less likely to occur. Massage two tablespoons of lemon juice into your scalp then rinse. Next, add one teaspoon of lemon juice to one cup of water, and use it to rinse your hair. Try this daily until you notice improvement.
Salt works because it's abrasive. When you massage some onto your dry scalp, it'll help to loosen flakes so they're easily removed when you shampoo.
8. Aloe Vera
If your dandruff is accompanied by irritation and itch, smooth some fresh aloe vera onto your scalp before you shampoo. It will help to cool your scalp and relieve irritation and itch.
Garlic is another natural antifungal, which can be crushed and rubbed into your scalp to help stop dandruff. To make it easier to apply and reduce the smell, try mixing it with honey first and then shampooing your hair as usual.
10. Olive Oil
Olive oil is traditionally said to relieve dandruff, possibly by moisturizing your scalp. Massage 10 drops into your scalp, put on a shower cap and leave it on overnight. Shampoo as usual in the morning.
11. Reduce Stress
Stress is known to trigger dandruff and make symptoms worse, so regular stress management is crucial for just about everyone. For some, this might include staying away from negative or overly stressed individuals, or at the very least turning off the nightly news if it is too upsetting, to avoid feeling empathic stress. Ultimately, however, what you do for stress relief is a personal choice, as your stress-management techniques must appeal to you and, more importantly, work for you.
If a round of kickboxing helps you get out your frustration, then do it. If meditation is more your speed, that's fine too. Energy psychology techniques such as the Emotional Freedom Techniques (EFT) can be very effective as well, by helping you to actually reprogram your body's reactions to the unavoidable stressors of everyday life.
12. Get Out in the Sun
Sensible sun exposure on your scalp may rid it of dandruff, as sunlight helps suppress the fungus that can cause dandruff.11 It will also help to optimize your vitamin D levels, which is known to be beneficial for skin health.
13. Consume Plenty of Zinc and B Vitamins
Zinc helps to control the production of oils on your scalp,12 and it's this excess oil that may encourage the growth of dandruff-causing fungus. B vitamins, particularly, vitamin B6, helps with proper zinc absorption in your intestines, and a vitamin B6 deficiency has been linked to dry skin and dandruff (zinc deficiency has also been linked to flaky skin like dandruff). Animal products, like oysters, grass-fed beef, cheese, and pastured chicken, are by far the richest of dietary zinc, but you can also find it in pumpkin seeds, sesame seeds, cashews, almonds, and in supplement form.Finally, remember that in order to get rid of dandruff for good, you need to address the underlying cause. If that cause is an overgrowth of yeast or fungus, you should tackle the problem by cutting down on your intake of sugar and grains, as these will rapidly increase the growth of fungus (worsening symptoms of dandruff). If you need help getting started on a healthier diet, my nutrition plan provides a step-by-step guide.