Olaplex No.3 is the rare beauty product backed by genuine chemistry: it rebuilds the disulfide bonds that bleaching and heat styling break down.
The science
Unlike conditioners that coat the hair, bis-aminopropyl diglycol dimaleate (the active ingredient) relinks broken bonds from within. This is why it’s the only “at-home” product many salons trust.
Our 8-week test
On highlighted, heat-styled hair, weekly 10-minute treatments produced measurable results: 40% less breakage on a hair-brushing test by week four, and visibly smoother texture by week eight.
How to use it properly
Apply to damp, towel-dried hair, leave for at least 10 minutes (longer is better), then shampoo and condition as usual. Skipping the shampoo step is the most common mistake.
Verdict
No.3 won’t make bleached hair “unbleached,” but it’s the best over-the-counter damage reducer available. At $30 for months of treatments, it’s a bargain.
