Has coffee overthrown cola as the caffeine king? Soft drink sales have been slipping over the past eight years, partially a result of public health officials targeting the sugary beverages as a leading cause of diabetes and obesity. More and more consumers have been opting for alternatives such as water, sports drinks and fruit juices, but the real competition lies in the humble coffee bean.

Coffee revenue is up 50 percent in the last decade, partially thanks to the immense popularity of national coffee chains, and partially thanks to research that finds there are little to no adverse health effects caused by coffee consumption. In fact, studies suggest the bean is effective in preventing certain cancers, as well as reducing the risk of dementia, Type 2 diabetes and depression among women.

Cola companies are also losing ground with a key demographic: 18- to 24-year-olds. This age group is more likely to drink a cup of coffee on a daily basis than they were a mere five years ago. Furthermore, in the last decade, the amount of 18- to 24-year-olds who reported drinking coffee in a two-week span increased by 56 percent.

But all the new java enthusiasts out there still need to be wary of one thing: how coffee can affect their slumber. Research shows that a “tall” Starbucks coffee has about five times as much caffeine as a can of Diet Coke. Depending on your genetics and how used you are to caffeine, a cup of coffee can stay in your system anywhere from two to 12 hours — which can easily interrupt a good night’s sleep. Studies show a correlation between high caffeine use and decreased REM, a crucial deep sleep state.

So while you’re not alone in reaching for a carafe instead of a can at 2 p.m., it could still make bedtime a nightmare.