Gestational diabetes?

Who had gestational diabetes while pregnant? How can lower my chances of getting it? Is eat snacks gonna make me get it? I haven't really been craving hun food.. cookies and cake and all that make me sick just looking at them.. iv basically been eating chips, fries, tacos, wedgies.. I usually never drank pop when I wasn't pregnant.. but lately iv been wanting it but only drink 1 or 2 every a week weeks and a half, when I do its caffeine free.