Quick answer: dandruff is a very common scalp condition that causes white or yellowish flakes, often with itching. It's linked to an overgrowth of a yeast that lives naturally on the scalp, excess oil, and how quickly scalp skin renews itself. It isn't caused by poor hygiene. Most dandruff can be managed with a purifying anti-dandruff shampoo used regularly, plus a leave-on scalp treatment. If flakes are small, fine and your scalp feels tight, you may have a dry scalp instead, which needs gentler care.
What is dandruff?
Dandruff is flaking of the scalp skin. Everyone sheds skin cells, but with dandruff the scalp sheds them faster and in visible clumps. Flakes tend to be white or yellowish, sometimes slightly oily, and often show up on the shoulders of dark clothes. It can come with an itchy scalp, and it tends to come and go.
What causes dandruff?
- Scalp yeast: a yeast called Malassezia lives on everyone's scalp. In some people it triggers irritation and faster skin shedding.
- Excess oil: the yeast feeds on scalp oil, so oilier scalps are often more prone to dandruff.
- Infrequent washing: it doesn't cause dandruff, but letting oil and flakes build up makes them more visible.
- Stress, seasons and hormones: many people find dandruff flares in winter or at stressful times.
- Product build-up: heavy styling products left on the scalp can add to flaking and itching.
Is it dandruff or a dry scalp?
- Flakes: dandruff flakes tend to be larger, yellowish or white and slightly oily. Dry scalp flakes are small, fine, white and powdery.
- How the scalp feels: with dandruff the scalp and roots often feel oily. A dry scalp feels tight and may look dry elsewhere too.
- When it's worse: a dry scalp is often worse in winter, with hot showers and central heating. See our winter hair care guide.
For a dry, tight scalp, choose gentle, soothing care instead, such as our itchy & sensitive scalp edit.
How to treat dandruff
1. Use an anti-dandruff shampoo regularly
Insight's Purifying Shampoo gently cleanses and purifies the scalp, with organic thyme, rosemary and sage extracts. It's free from SLS and SLES. Apply to damp hair, massage it gently into the scalp rather than the lengths, and rinse thoroughly.
2. Add a leave-on scalp treatment
Purifying Scalp Treatment is a lightweight, no-rinse lotion that purifies and normalises the scalp and helps keep it clean for longer, with panthenol and a cooling touch of menthol. Apply it to a clean, towel-dried scalp and massage in.
How often: for an intensive treatment, apply the Scalp Treatment once a day, or at least three times a week, for three weeks. For maintenance, use it once or twice a week for six weeks.
3. Keep your routine consistent
Dandruff tends to come back when you stop. Wash regularly, keep the scalp free of build-up, and go back to the intensive routine if flakes return.
What the testing showed
In vivo efficacy tests showed that using Purifying Shampoo and Purifying Scalp Treatment together made dandruff flakes less visible. In a separate consumer test of 20 volunteers, all of them said the Clarifying range had a purifying effect, that the shampoo removed impurities, and that the treatment helped keep their scalp clean for longer.
Shop the Clarifying anti-dandruff range.
Dandruff and an oily scalp
If your scalp is oily as well as flaky, keeping oil under control helps. A weekly Scalp Exfoliating Cream before shampooing lifts away oil and build-up, and Rebalancing Shampoo keeps oily roots fresher for longer. See the oily scalp edit and Scalp scrubs: do you need one?
What about beard dandruff?
Flaky, itchy skin under a beard is common, and it often behaves just like scalp dandruff. Many of the barbers we work with tell us they use Rebalancing Shampoo to cleanse oily, flaky beards, and that it works wonders. Massage a small amount into the beard and the skin underneath, then rinse thoroughly. Rebalancing is formulated for the scalp, so if your skin is sensitive, try it on a small area first and keep it away from your eyes.
Is anti-dandruff shampoo the same as clarifying shampoo?
Not quite. A clarifying shampoo deep-cleans, removing build-up from oil, styling products and hard water. An anti-dandruff shampoo targets the causes of flakes on the scalp. They overlap, but a clarifying shampoo won't necessarily help dandruff.
When to see a professional
See your GP or pharmacist if flakes are thick, crusty or spreading beyond the scalp (for example to the eyebrows, sides of the nose or beard), if your scalp is very red, sore or weeping, or if things don't improve after a few weeks. Persistent flaking can be a sign of seborrhoeic dermatitis, psoriasis or another condition that may need medicated treatment.
Frequently asked questions
Can dandruff be cured permanently?
Dandruff tends to come and go, so most people manage it rather than cure it. A consistent routine keeps flakes under control, and you can step it up when they return.
Should I wash my hair more or less if I have dandruff?
Usually more regularly, not less. Leaving oil and flakes to build up tends to make dandruff more visible.
Is dandruff caused by poor hygiene?
No. Dandruff is linked to scalp yeast, oil and skin renewal, not cleanliness, though infrequent washing can make flakes more noticeable.
Can a dry scalp cause dandruff?
They're different conditions, but you can have both, and a dry, irritated scalp can make dandruff feel worse.
Does a scalp scrub help dandruff?
A scalp scrub can lift loose flakes and build-up, but it doesn't replace an anti-dandruff routine. Avoid scrubbing a red, sore or broken scalp.
I have an itchy scalp but no dandruff. What is it?
An itchy scalp without flakes is often a sensitive or irritated scalp. Read our guide to the best shampoo for an itchy scalp.
About the author
Charlotte Read has spent six years in the hair industry with Insight Professional and holds a First Class BSc in Business Management and Marketing. She writes with reference to real salons across social media and the wider Insight community, and draws on the Insight office team, who between them bring over 100 years of combined experience on salon floors.
Where technical expertise is needed, Charlotte consults Lorraine Matic, Head of Insight UK Education, who brings over 38 years of global experience in colour, technique and hair science.