Hey, Crista, and welcome to DFA!
Yes, Beneful is not a good food at all, so I would definitely advise you to change your Yorkie to something else. However, changing directly to a high-quality food may seriously upset his tummy, so I would recommend switching him gradually to Nutro or some other medium-level brand, and after a little while, switching him over to a good-quality food.
Off the top of my head, Castor and Pollux Organix is a good-quality dry, organic meat-and-veggie-based food. Their other line, Ultramix, is also really, really good, but not quite all-organic. http://www.castorpolluxpet.com/our-products
Since you are an Editor’s Choice member on this site, I believe you have access to a list of GMO-free foods: /reports/gmo-free/
Just look through that, they are all quality foods to choose from. Good luck!
