Most people love their morning cup of coffee, or an afternoon energy drink, or an evening latte.  But a new study is examining whether reliance on caffeine is just a harmless habit or a more serious problem.  The team of researchers from American University, the Johns Hopkins School of Medicine, and the University of Vermont has found that some people suffer from what's known as "caffeine use disorder."  The report lists the criteria for the disorder as people who want to reduce or stop using caffeine but can't, and who suffer withdrawal symptoms like headaches, fatigue or sickness when they do quit.  "It's another way of calling it caffeine addiction," says Dr. Grant Fowler, Professor of Family and Community Medicine at UT Health Medical School.  "We know there are caffeine receptors in the brain, and everybody has kind of a different response to it."


While regular or moderate use of caffeine is fairly common and not considered harmful by most health experts, this study focused on a much smaller segment of people.  While it stops short of referring to "caffeine addiction," it does refer to people who truly can't function normally without large quantities of caffeine.  Some of these people may even resort to energy drinks or pure espresso shots as a stronger dose of caffeine than a traditional cup of coffee.  Dr. Fowler admits there are concerns about these newer, more potent sources of caffeine.  "I worry long-term what's going to be the effect on your sleep at night," he says.  "That (energy drinks) give you more energy and it persists longer, and will you crash afterward."


Dr. Fowler agrees that most caffeine use is not dangerous.  In fact, he says small or moderate caffeine intake actually has health benefits.  But, there are certain signs for people to watch for.  "If you have persistent palpitations, some people can have an irregular heartbeat, if you have stomach problems, or the headaches," says Dr. Fowler.  Generally, he sees those headaches as the most persistent symptom of heavy caffeine use.  "Some people have to make a choice," says Dr. Fowler.  "Is it worth the headache for the caffeine?"