Oprah Winfrey and America's favorite physician -- Dr. Memhet Oz -- want you to know they don't endorse dozens of açaí berry products that claim their seal of approval -- and they're suing to prove it. "Many Americans have seen images of me, and Oprah and others supporting, it would appear, products that actually don't work in the ways that are described," Oz said in an exclusive interview Thursday with ABC's "Good Morning America." "And more importantly, when consumers trusting us try to buy these products over the Web, what they end up getting are fake products, pills that don't really have what's promised in them. They're often duped into paying more than they should. If my picture is next to a product, endorsing it and supporting your purchase of it, I did not give them permission." 

Winfrey and Oz have filed suit against 40 companies either selling açaí or related products, with their name endorsements on them. 

According to their complaint, such companies are "fabricating quotes or falsely purporting to speak in Dr. Oz's and/or Ms. Winfrey's voice about specific brands and products that neither of them has endorsed." 

"Consumers should be aware that neither Oprah Winfrey nor Dr. Oz are associated with nor do they endorse any açaí berry product, company or online solicitation of such products, including MonaVie juice products," a statement read on Winfrey's Web site. "Neither Oprah nor Dr. Oz are associated with nor do they endorse any specific resveratrol product, company or online solicitation of such products. Any companies that misrepresent their affiliation are making false claims."