In short
- Bleach breaks disulfide bonds in the hair cortex — the structural bonds, not just surface.
- Bond repair systems (Olaplex, K18, Wella WeDo) chemically re-link broken bonds.
- Full recovery of severely bleached hair takes 6–9 months of consistent bond work.
- Salon in-treatment bond repair (£40–£90 add-on) outperforms home-only routines.
Bleach lifts colour by breaking the disulfide bonds that hold the hair cortex together. What looks like 'dry' bleached hair is actually structurally weakened hair — no amount of oil replaces broken bonds.
How bond repair chemistry works
Bond repair systems use small molecules that penetrate the cortex and re-form the broken bonds. Olaplex uses bis-aminopropyl diglycol dimaleate; K18 uses a peptide that mimics natural keratin; Wella uses maleic acid derivatives. All three work; the differences are formulation and application.
The 90-day recovery protocol
- Salon bond treatment at week 0 (£40–£90 as add-on to a wash).
- Weekly home bond mask (Olaplex 3, K18 mask, Living Proof Triple Bond Complex).
- Alternate weeks: hydrating mask (glycerin + ceramide).
- Daily leave-in with a lightweight bond primer.
- Cut off the worst 1–2cm to reset ends.
- Salon assessment at 90 days — often a second bond service is warranted.
What not to do
Do not re-bleach until bond structure is rebuilt. Do not use protein-only masks daily (over-protein makes brittle hair worse). Do not skip the cut — split ends only get worse with time.
You cannot condition your way through bleach damage — you have to rebuild the structure.
Frequently asked
Common questions
Can bond repair fully reverse bleach damage?+
It restores 60–80% of structural integrity in most cases. The remaining damage grows out.
Is K18 or Olaplex better?+
Different chemistries with similar outcomes. K18 requires no rinsing; Olaplex is more established. Trial both and choose by feel.
How long before I can bleach again?+
Wait at least 12 weeks after severe damage. Insist on a strand test and a bond additive in the bleach itself.
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