The Scalp-Hair Connection
Hair grows from follicles embedded in the scalp's dermis. Each follicle is surrounded by sebaceous glands (which produce the oils that coat the hair shaft) and a dense capillary network (which delivers nutrients to the growing hair cell).
When the scalp is inflamed, congested or lacking circulation, follicle function decreases. The most direct visible result is hair growth rate and thickness. A scalp with chronic inflammation or blocked follicles produces thinner, shorter hair over time than the same follicles in a healthy environment.
Dandruff vs Dry Scalp: The Most Common Confusion
Dandruff and dry scalp produce the same symptom (white flakes) but have opposite causes and opposite treatments.
Dandruff: Caused by Malassezia, a yeast that lives on all human scalps and proliferates when conditions favour it (excess sebum, warmth, humidity). The yeast triggers an inflammatory response, causing rapid skin cell turnover and the characteristic greasy, yellow-white flakes.
Dry scalp: Caused by insufficient moisture and oil on the scalp surface. Flakes are smaller, drier and whiter than dandruff flakes. The scalp feels tight and may itch after washing.
How to tell the difference: Dandruff flakes are larger, greasier and appear primarily at the roots. Dry scalp flakes are smaller and more powdery and distribute evenly across the scalp.
Dandruff treatment:
- Ketoconazole shampoo (e.g. Nizoral): 1% OTC, 2% prescription. Use twice weekly for 4 to 8 weeks, then maintain once weekly.
- Zinc pyrithione shampoo: Antifungal; slower-acting than ketoconazole but effective for maintenance.
- Selenium sulphide: Effective for moderate to severe dandruff.
Dry scalp treatment:
- Switch to a sulphate-free, hydrating shampoo
- Reduce wash frequency to allow natural oils to condition the scalp
- Apply a lightweight scalp oil (jojoba, grapeseed) or scalp serum before washing once a week
Describe your scalp symptoms, including flaking type, itching pattern, oiliness and any recent product changes. The Hair Chat Advisor identifies the most likely scalp condition and recommends the treatment approach, including which shampoo ingredients to look for.
Ask About My ScalpAnalyse My Hair and ScalpScalp Oiliness: Causes and Regulation
An oily scalp produces visible roots within 24 to 36 hours of washing. The causes are hormonal (androgens stimulate sebaceous glands), genetic and, frequently, product-related.
Product-related oiliness: Silicone-heavy conditioners and styling products coat the scalp and trap sebum. The scalp reads this as insufficient oil and increases production. Switching to silicone-free products often reduces oiliness within 4 to 6 weeks.
Over-washing: Washing every day strips the scalp of natural oils, which triggers the same compensatory response. Spacing washes to every 2 to 3 days over 4 to 6 weeks resets the oil cycle for many people.
Scalp-specific treatments for oiliness:
- Niacinamide scalp serums (same oil-regulating mechanism as on facial skin)
- Salicylic acid scalp treatments (BHA dissolves sebum build-up in follicles)
- Scalp massages for 5 minutes before washing to loosen sebum before shampooing
Scalp Psoriasis: What It Looks Like and What to Use
Scalp psoriasis produces thick, adherent silver-white plaques that extend beyond the hairline onto the forehead and behind the ears. It is an autoimmune condition, not a hygiene issue.
OTC management options:
- Coal tar shampoos (Polytar, T-Gel): Slow cell turnover. Effective but strong in odour.
- Salicylic acid treatments: Soften and lift plaques.
- Zinc pyrithione: Reduces inflammation.
For moderate to severe scalp psoriasis, seek a dermatologist assessment. Prescription-strength topical corticosteroids and biologic treatments are more effective than OTC options for significant involvement.
Hair Follicle Clogging and What Causes It
Product build-up on the scalp clogs follicle openings and reduces healthy oil flow along the hair shaft. The result is dull hair, a flaky or itchy scalp and, over time, slower growth.
Common culprits:
- Dry shampoo used daily (the starch and silica absorb sebum but accumulate on the scalp if not properly washed out)
- Heavy styling products applied to the root (serums, thick creams)
- Silicone build-up from conditioners
Scalp exfoliation: A physical or chemical scalp scrub used once weekly removes product build-up and dead skin cells from follicle openings. Physical scrubs use fine sugar or salt particles. Chemical scalp exfoliants use salicylic acid or glycolic acid.
Do not massage a physical scrub directly into the scalp with heavy pressure. Work in circular motions with fingertip pressure, not with nails.
The Weekly Scalp Care Routine
| Day | Action | Product |
|---|---|---|
| Day 1 | Shampoo + condition | Sulphate-free shampoo; condition mid-lengths to ends |
| Day 2 | Rest | No product at root |
| Day 3 | Rest or dry shampoo to mid-shaft only | Avoid dry shampoo at scalp |
| Day 4 | Shampoo + scalp treatment | Add salicylic or niacinamide treatment before shampooing |
| Day 5 | Rest | No product at root |
| Day 6 | Pre-wash scalp oil (optional) | Jojoba or lightweight scalp oil, left 30 minutes before wash |
| Day 7 | Shampoo + condition | Standard wash cycle restarts |
This schedule reduces wash frequency, allows sebum regulation and incorporates targeted scalp treatment without over-processing the hair shaft.