Answer:
Yes, if they are based on clear evidence, otherwise your claims will be misleading and deceptive. For example, Listerine previously claimed that rinsing with Listerine mouthwash was as effective as flossing in fighting gum decay. These claims were unsubstantiated with scientific evidence and the maker of Listerine was ordered to remove these ads. You need to make sure you have a reasonable factual basis for the scientific claims you make and that any percentages you use in your claims are based on truthful evidence.
