The best diet advice you'll ever receive is "don't put anecdotal dietary advice into action unless it came from a qualified dietician".
My state at least requires a 4 year education in an area approved by the state board of dieticians to call oneself a nutritionist... but that's a far cry from the 8 year education requirements plus board certification and testing required to become a registered dietician here. IIRC they are even developing something akin to residency requirements going forward.
But in some states there are literally no legal protections on the title of nutritionist. I wonder if any aspiring dietary health bloggers (who perhaps became experts in nutrition via facebook posts) have moved residence to capitalize on this situation...