In short
- London water hardness (270–320 ppm) deposits calcium and magnesium on hair and scalp.
- Symptoms: dullness, faster fade on colour, dry mid-lengths, scalp itch.
- A £40 shower filter solves 80% of the problem in 2–3 weeks.
- Monthly chelating treatments restore hair that has accumulated long-term mineral build-up.
London tap water hardness sits between 270 and 320 ppm — significantly above the European average. Over time, the calcium and magnesium in this water deposit on the hair shaft and scalp, dulling colour, weakening the cuticle and disrupting the scalp microbiome.
Symptoms most Londoners blame on the wrong thing
Colour that fades faster than the salon promised. Hair that 'just feels different' after moving to London. Mid-length dryness despite good products. Persistent scalp itch with no flaking. All four are classic hard water signatures.
The fixes that work
A KDF-55 shower filter (£35–£60) installed at the showerhead. A monthly chelating treatment at home (EDTA-based) or in-salon (£35–£85). For coloured hair: a weekly clarifying rinse with citric acid (or apple cider vinegar diluted 1:4).
Frequently asked
Common questions
Do shower filters really work?+
Yes, when KDF-55 based. Carbon-only filters reduce chlorine but not mineral content. Look for KDF-55 explicitly in the spec.
Can hard water cause hair loss?+
Not directly, but it can worsen scalp conditions that contribute to loss. Treat the scalp environment, not just the symptoms.
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