Dr Kara Johns
Creator and Director of SBK
hello@sbk.store

If you’ve ever glanced down at a dark t-shirt and spotted flakes on your shoulders, “dandruff” is probably the first word that comes to mind. I remember this was the word my mum used any time I mentioned something about my scalp as a child!  It’s the word most of us reach for. But dandruff is actually just the everyday name for one specific condition — and it’s not the only reason a scalp flakes.

A flaky scalp can be caused by several conditions and working out the cause is the first step to addressing it.  Lets go through the real, diagnosable conditions that cause a flaky scalp - what they look like and when it is times to get it checked out. 

1. Seborrhoeic Dermatitis (Dandruff)

The most common cause of an itchy, flaky scalp. It shows up as greasy, yellowish scale in oil-rich areas — scalp, hairline, eyebrows, sides of the nose. 'Dandruff' is actually the mildest form of this same condition — the uninflamed version, without the redness. 'Cradle cap' is the infant version.

What’s actually happening: the exact cause of seborrhoeic dermatitis is not fully understood, however, it seems to be from a combination of hormonal, nutritional, yeast and neurological factors. It is not about hygiene, and it comes and goes in flares, often worse with stress or in winter.

Managing it: there are 2 main approaches to management - reduce the yeast with ingredients like ketaconazole, and encourage cell shedding with salicylic acid - the process of the outer dead skin cells releasing rather than being sticky.

2. Scalp Psoriasis

Distinguished by thick, well-defined, silvery-white plaques with redness underneath. Unlike seborrhoeic dermatitis, the scale is drier and more built-up, and it can extend past the hairline onto the forehead or behind the ears. It can flake heavily, and the flakes tend to be larger and more stubborn than dandruff’s fine dusting.

What’s actually happening: psoriasis is an immune-driven condition where skin cells are produced far faster than normal, so the stratum corneum — the outermost layer of dead skin cells — builds up faster than it can shed. That build-up is the plaque you can see and feel.

Managing it: because it’s fundamentally a build-up problem, keratolytics like salicylic acid are a cornerstone of management — they work by breaking down the excess keratin holding the scale together, helping it lift and clear. This is usually paired with anti-inflammatory treatment from your doctor to address what’s driving the overproduction underneath.

3. Tinea Capitis (Scalp Ringworm)

A fungal infection, more common in children, causing scaly, flaky patches — sometimes with broken hairs or small bald spots.

What’s actually happening: a fungus invades the hair shaft itself, not just the surface of the skin, which is why it needs a different approach to treat.

Managing it: topical treatment alone can’t reach a fungus living inside the follicle — this one needs an oral antifungal, prescribed after proper diagnosis. It’s also contagious, so combs, hats, and pillowcases need attention too.

4. Discoid Lupus Erythematosus (DLE)

This one is rare, but worth knowing about because it’s easy to mistake for something more benign. DLE causes persistent, scaly, disc-shaped plaques, often on the scalp, face, or ears, that can look deceptively like a stubborn patch of dandruff or psoriasis at first glance.

What’s actually happening: DLE is a chronic autoimmune skin condition, where the immune system targets the skin itself, causing inflammation and thick adherent scale. Left untreated, it can progress to scarring and permanent hair loss in the affected area — which is what separates it from every other cause on this list.

Managing it: this isn’t a self-care condition. It needs a medical doctor to diagnose and prescribe ongoing management. The reason it’s worth knowing about is timing — the earlier it’s caught, the more hair loss can potentially be prevented.

When It’s Not a Medical Condition at All

Not every scalp flake landing on your shoulder means there is an underlying medical condition. A common, non-medical cause of flaking is simply product build-up — residue from waxes, gels, and heavier styling products layering on the  hair or scalp over time, especially when combined with infrequent or ineffective washing. The “flakes” here are often more of a waxy residue than true skin shedding, and they usually resolve with a proper wash routine — though a gentle keratolytic (salicylic acid!) can help lift any residue that’s bonded to the scalp surface, making washing more effective.

When to See a Doctor

I always want you to know where self-care ends. See a GP or dermatologist if:

• Flaking hasn’t improved after a couple of weeks of gentle, consistent care
• There’s redness, pain, pus, or spreading irritation
• You notice hair loss or bald patches
• It keeps coming back despite doing “everything right”

These conditions can look remarkably similar from the outside, but they need different treatments — so getting the right diagnosis saves you time, money, and frustration.

Caring for a Flaky Scalp, Gently

While you work out what’s driving it, some general principles help almost every scalp:

• Avoid fragrance in hair and scalp products where you can — it’s a common irritant that can worsen inflammation-driven flaking
• Get your wash routine right for you — both over-washing and under-washing can make flaking worse, depending on the cause
• Be gentle with heat and heavy styling products, which can aggravate an already irritated scalp
• Look for a keratolytic ingredient like salicylic acid to help gently clear existing scale and buildup, rather than just masking flakes for a day
• Consider ingredients that support the scalp microbiome - such as lactobacillus ferment.
• Consider ingredients that promote calm healthy scalp skin - such as green tea extract, centella asiatica extract and rice extract.
• Resist the urge to self-diagnose long-term — what looks like “just dandruff” for months may be something else entirely

Watch This Space

Scalp care has been on my mind for a while now — for all the reasons above. We will be releasing a scalp product soon, formulated with the same evidence-based, fragrance-free approach behind everything else we make. 

If your scalp has been bothering you, you’re not alone — and you don’t need to just live with it. Understanding what’s actually going on is the first step.

This blog will be updated soon!