The Science Behind Wella

Yes. Wella Professionals’ ULTIMATE REPAIR range harnesses AHA (Alpha-Hydroxy Acids) and Omega-9 (a bio-identical lipid) to repair the hair fiber from the inside out. AHA is an acid so tiny, it’s able to penetrate the cortex, where it repairs broken bonds. Meanwhile, Omega-9 recreates the outer protective layer of the hair to keep it smooth and protected. This dual-action system helps to repair hair damage in 90 seconds³, giving you up to 99% less breakage⁴ and up to 12x smoother hair⁵.

Copper ions – which accumulate in your hair from the water you wash with – are one of the most common culprits behind unexpected color results. They cause an oxidative reaction that can disrupt the way color develops. Metal Purifier Technology helps by encapsulating metal ions in the hair before they react, leading to true-to-tone color results.

For Wella Professionals, "dermatologically tested" means the product has been evaluated under a standardized protocol and supervision by a dermatologist to confirm it does not cause skin irritation or sensitization under normal conditions of use.

Yes, Alpha-Hydroxy Acids have been scientifically proven to support hair health, with established cosmetic chemistry research backing up the results. At the right concentration and pH, they can work as deep as the hair cortex, helping to support the rebuilding of internal bonds. AHA plays a key role in the ULTIMATE REPAIR collection, working alongside Omega-9 to repair the hair from the inside out.

This claim is generated via a standardized test method involving a combing robot that applies consistent speed and force to all test tresses. Each test includes a control set of untreated tresses and a set of tresses treated with the product, with all hair tresses prepared under the same damage conditions prior to product application. The percentage reduction refers to the difference in fiber breakage events between treated and untreated hair under identical mechanical stress conditions.