Experts explain how the products work on hair's broken bonds — and who actually needs them.
Bond repair products target the disulfide, hydrogen, and salt bonds inside each hair strand's cortex, using ingredients like amino acids, hydrolyzed proteins, and peptides to reconnect or fill gaps left by damage, according to hairstylist Izzy Dickinson and Äz Haircare founder Rodger Azadganian, who spoke to Elle.
Dickinson said the treatments are especially useful for hair damaged by bleaching, coloring, heat styling, or everyday stressors like sun exposure, hair ties, and friction from brushing. Azadganian was more cautious, saying that while the right products can improve hair's look and feel over time, there's "rarely an overnight fix" — he estimates it takes 90 to 120 days of consistent use before most people notice a meaningful difference.
Both experts agreed that anyone with over-processed or chemically treated hair is likely to see the most benefit, though even untouched hair can develop weakened bonds from daily wear. Azadganian compared bond repair to taking a multivitamin: not strictly necessary if your hair is already healthy, but not harmful to add to a routine either.
Dickinson said a properly formulated bond repair product shouldn't damage healthy hair, unlike protein-heavy formulas that can make hair brittle if overused. She recommended matching the product format to what hair actually needs — a shampoo and conditioner for everyday support, a mask for more intensive treatment, or a serum for targeted care.
