Once those bonds are broken, the strand loses strength and elasticity. It feels rough when dry, stretchy when wet, and snaps more easily under a brush. The K18PEPTIDE was designed for exactly this damage. It is small enough to travel into the cortex and reconnect the broken keratin chains, which is why bond repair, not surface conditioning, is the foundation of any real recovery plan.

If you want the full chemistry of how bleach changes the strand, we break it down in our guide on what bleach does to your hair.

• Gummy or mushy when wet, like wet wool, means the cortex has lost its bonds.
• Stretchy and slow to recover points to lost elasticity from over-processing.
• Dry, rough and snapping at the mid-lengths usually means the cuticle is gone and breakage has started.

We cover the diagnosis and recovery in detail in our guides on how to fix gummy hair and how to fix elastic hair after bleaching.

• Treat with a bond builder in the days beforehand so the strand starts from a position of strength.
• Avoid stripping or clarifying right before, which can leave the cuticle raised and uneven.
• Tell your colourist about any recent chemical services, since stacked processes compound the damage.

The full prep routine, including timing, is in our guide on how to prepare your hair before bleaching, and the wider protection plan is in how to prevent bleach damage.

Going lighter in one sitting is where most damage happens. Spreading a big lift across multiple appointments, with repair in between, protects the strand far better than chasing platinum in a single chair session.

We set out the timing in full in how often you can safely bleach your hair and how long to wait between bleaching sessions.

• Detox first so product build-up and hard-water minerals do not block the repair.
• Treat with the leave-in mask, the step that does the structural work.
• Seal with the molecular oil to smooth the cuticle and add heat protection.

The full at-home method is in how to repair bleached hair at home, and the plan for hair that is already badly over-processed is in how to treat damaged bleached hair.

Set your expectations to the goal. Strength and reduced breakage answer in days to weeks. Growing out fried ends is a months-long job measured by how fast your hair grows, which is roughly one to one and a half centimetres a month. Patience plus consistency beats any single heavy treatment.

We explain the biology of why this takes time in why hair health takes time to rebuild, with a broader recovery plan in how to restore damaged hair.