If you put the words "clinically proven" in your advertisement then you might as well have fraud written in bold letters at the bottom of the screen. I don't care if what you are selling does actually work, I am not going to believe you if you say it is clinically proven. Those two words rate right up there with "4 out of 5 Doctor's agree" in the vague statistics category. The only thing that might be more annoying are the before and after photos which make you wonder throughout the entire ad if they are the same person or if they were photoshop'd.
If your medicine/diet/hair growth is so great, why do you need a commercial? Why isn't there a buzz in the medical world? Why aren't patients and doctors writing about their experiences online? Make something worthy and people will spread the word for you.