True or false: Does shampoo necessarily have to lather to be effective?. The origin of this preconceived idea? “The foam has a dispersing action, we compare it to washing,” according to Denise Guillouet.
The L'Oréal Paris expert warns us: it will be more difficult to remove and will make the hair greasy. A small amount in the palm of your hand is enough. It will be useful to make two if a dry shampoo has been used before.