In short
- Dry scalp is usually a barrier lipid deficiency, not dehydration.
- Hot water, high-pH shampoos and heavy fragrance all worsen it.
- Ceramide-based scalp serums restore barrier faster than any oil.
- London hard water contributes — a shower filter helps in about a third of cases.
The dry, tight, sometimes flaky scalp is a barrier problem. The outer layer of the scalp is made of lipids — ceramides, cholesterol, and fatty acids — that keep water in. When those lipids are disrupted, water evaporates faster than it can be replaced.
What's stripping the barrier
- Water hotter than 40°C.
- Sulfate shampoos used daily.
- Fragrance and essential oils in leave-on products.
- London hard water (calcium and magnesium disrupt the barrier).
- Winter indoor heating without a humidifier.
The rebuild protocol
Wash 2–3 times a week with a sulfate-free hydrating shampoo. Between washes, apply a ceramide + niacinamide scalp serum to the parting. Twice a week, do a 20-minute pre-wash mask with squalane or lightweight jojoba oil — heavy oils clog follicles.
Water and environment
A shower filter (£80–£150) removes calcium and chlorine from London's hard water; a bedroom humidifier at 40–50% humidity through winter helps significantly. Both are underrated interventions.
The scalp is skin. Treat it like face skin and the drama subsides.
Frequently asked
Common questions
Coconut oil for dry scalp — good or bad?+
Coconut oil is comedogenic and heavy for the scalp. Lighter oils (jojoba, squalane) work better without clogging.
How do I tell dry scalp from dandruff?+
Dry scalp flakes are small, white, non-greasy; dandruff flakes are yellow, greasy, larger, and usually itch more.
Does drinking more water help?+
Modestly. Barrier support (topical ceramides, humidifier, filtered water) helps far more than oral hydration alone.
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