Bond repair shampoos and treatments: do they fix bleached hair or just coat it?

Bleached twice this year, hair snaps when I brush it. Olaplex, K18 and every "bond repair" shampoo promise to fix it. Is any of this real, or is it conditioner with a story?

Some of it is real, some of it is conditioner with a story, and the word "repair" is doing a lot of work either way.

What bleach does: it breaks disulfide bonds inside the hair. Broken bonds are why it stretches, snaps and feels like straw.

What the real bond builders do: Olaplex's active ingredient (bis-aminopropyl diglycol dimaleate) and K18's peptide both reconnect some of those broken bonds. The in-salon steps during the bleach service do the most; the at-home versions (Olaplex No. 3, K18 leave-in) maintain and add a little. Results are real but partial: less breakage, more stretch before snapping, better feel. It does not become virgin hair.

What the shampoos do: the "bond repair" shampoos mostly keep the hair clean without stripping and carry a small dose of the actives. Fine as maintenance, not the fix.

What nothing fixes: split ends. Once the end has split, cut it. Anything that claims to seal splits is glue that lasts until the next wash.

For your case: a proper treatment every one to two weeks for a couple of months, a trim now, and, more than any product, longer gaps between bleach sessions and a lower-volume developer next time. The treatment cannot outrun the damage if the damage keeps coming.