Perricone is a good huckster for the supplements and creams that he sells at a high price.
Heavy on promotion, light on facts...he makes a good presentation on the PBS pledge drives.
His biggest mandate seems to eat wild salmon a lot for a wrinkle-free skin!
Quackwatch has a lot to say about him.
He makes lots of overstatements and half-truths.
A good rule of thumb is to distrust anyone who is SELLING his own stuff. Personally, I wouldn't bother with him but there are a lot of people with more money to throw away than I.