Oily scalp: how often to wash and what actually helps

If your roots look flat and greasy by the evening, you may have been told to wash less so your scalp "learns" to make less oil. There is little evidence that this works. In most cases the better advice is to wash as often as your scalp needs, and to match the products to your hair.

Quick answer: Wash as often as your scalp feels oily. For many people with an oily scalp and straight hair, that means daily. Use a gentle shampoo on the scalp, conditioner on the ends only, and dry shampoo as a short bridge between washes. Salicylic acid or zinc shampoos can help with oil and flakes. Red, itchy, flaky patches may be seborrheic dermatitis and need a medicated shampoo.

Why does the scalp get oily?

The scalp has many oil glands that make sebum, a natural oil that protects hair and skin. How much oil you make varies from person to person, and hormones play a part. That is one reason oiliness can change during puberty or around your period.

Other things make hair look greasy faster:

• Hair type. Straight and fine hair shows oil quickly, because oil can travel down the strands easily. Curly and coily hair can feel drier, even when the scalp makes plenty of oil.
• Heat, sweat and humidity. Exercise, hot weather, hats and scarves can all add to the feeling of grease.
• Heavy products near the roots. Conditioner, oils, butters and serums applied to the scalp can weigh hair down.
• Not rinsing well. Leftover shampoo or conditioner can leave a film that feels greasy.

Does washing more or less change your oil?

Many people say that washing less retrained their scalp. The research on this is thin. What we do know is that oil and product build up on the scalp between washes, and this can make hair look limp. On the other hand, harsh shampoos and hard scrubbing can irritate the scalp. A gentle, regular wash is a safe middle path.

How often should you wash?

The American Academy of Dermatology (AAD) suggests matching your washing to how quickly your hair gets dirty or oily. For an oily scalp with straight hair, that usually means shampooing daily. Dry, textured, curly or thick hair often needs washing less often, from a few times a week to every few weeks. See oily scalp and hair for more on matching routines to hair type.

A routine for an oily scalp

1. Shampoo the scalp, not the full length. Massage with your fingertips, not your nails.
2. Double shampoo when very oily. The first wash removes oil and products, the second cleans more deeply.
3. Rinse well with warm, not hot, water.
4. Put conditioner on the lengths and ends only. Fine or straight hair often does best with conditioner on the ends. See conditioners.
5. Use a clarifying shampoo once every week or two if you use lots of styling products. Browse shampoos for options.
6. Use dry shampoo as a bridge, not as a replacement for washing. Dry shampoo absorbs oil, but the oil and product are still on your scalp. See dry shampoo.
7. Avoid heavy oils and butters on the roots.

Ingredients that may help

You can read about scalp actives and anti-dandruff ingredients on their own pages. People with sensitive scalps may prefer fragrance-free products. Patch test any new scalp product on a small area first.

Is it an oily scalp or seborrheic dermatitis?

Seborrheic dermatitis is a common skin condition that causes red, scaly patches, often with itching. On the scalp it can look like flaky dandruff, or like scaly patches with redness. It is linked to a yeast that lives on everyone's skin, as well as oil and an inflammatory reaction, and it often flares and settles. It is not caused by poor hygiene.

If your scalp is oily and also flaky or itchy, try an anti-dandruff shampoo with one of the ingredients above. The NHS says to use the shampoo as directed for up to four weeks. A pharmacist can help you choose. If it does not help, or the scalp is red, sore or swollen, see a doctor. They may suggest a stronger medicated shampoo or a short course of a prescription lotion. See dandruff and flaky scalp for more.

Mistakes that make oily hair worse

• Piling on dry shampoo day after day without washing.
• Harsh, stripping shampoo on the lengths. This can leave ends dry while roots stay oily. Aim the shampoo at the scalp.
• Hard scrubbing or very hot water, which can irritate the scalp.
• Heavy oils and butters on the scalp.
• Skipping the rinse. Product left behind can make hair feel greasy.

How long until you see results?

Hair should look and feel cleaner from the next wash. Changes in how fast it gets oily, if they happen, usually take several weeks of consistent care. Anti-dandruff shampoos need regular use for a few weeks before you can judge them.

When to see a dermatologist

• Red, itchy, flaky or scaly patches on the scalp, face or body.
• No improvement after about four weeks of anti-dandruff shampoo.
• A scalp that is sore, swollen, or has pus-filled bumps.
• Sudden oiliness with acne, irregular periods or extra hair growth, which can sometimes be linked to hormone changes.
• Hair thinning or increased shedding. See thinning hair and shedding.

FAQ

Does washing daily damage hair?

Not with a gentle shampoo on the scalp and conditioner on the lengths. For oily scalps, dermatologists often recommend daily washing.

Will cutting my hair help?

Shorter hair may look less flat, but the scalp makes the same amount of oil.

Can I use dry shampoo every day?

It is better as an occasional bridge. Wash your scalp regularly so oil and product do not build up.

Does diet change scalp oil?

There is little good evidence for a direct effect. If you are worried, a balanced diet is good for your general health.

Why is my hair oily at the roots but dry at the ends?

Oil is made at the scalp, so the roots can look greasy while the ends, which get little of it, stay dry, especially if they are damaged or colored. Shampoo the roots, and put conditioner on the ends.

Sources

• Tips for healthy hair (American Academy of Dermatology)
• Seborrhoeic dermatitis (DermNet)
• Dandruff (NHS)