It seems most people need a jolt from java in the morning (and maybe a few more boosts later in the day), but for some, that regular hankering can actually be Caffeine Use Disorder (CUD). The World Health Organization recognizes CUD, as they do other drug dependencies-not that you've necessarily heard of CUD before. So how do you know if you have it? That's what Laura Juliano, PhD, a psychology professor at American University, set out to determine when she teamed up with colleagues to specify CUD's symptoms and causes in a review just published in the Journal of Caffeine Research. Photo by Jonny Valiant; Prop styling by Marina Malchin.