The claims made by puffery may be false, but they are not really lies because no one can disprove them. No one can prove them either. A company may claim that its hamburger is the best hamburger in the world. No one can prove the hamburger is really the best, but no one can prove it is not. However, if the advertiser says that its hamburger contains ingredients that help to prevent cancer, that is something science could prove or disprove. Trying to persuade someone that hamburgers prevent cancer would be a false claim.
Hyperbole