You might want to think twice about consuming that afternoon cup of coffee or another caffeine containing beverage. While it might alleviate a mid-afternoon brain drain slump, it could affect your sleep that night, resulting in lower energy the next day. It has long been suspected that caffeine can disrupt sleep long after it has been consumed. Now there is data to support that avoiding caffeine in the later afternoon and evening can result in longer sleep. A recent study in The Journal of Sleep Medicine found that 400 mg of caffeine- equal to about 2-3 cups of coffee- taken at bedtime, 3 hours before bedtime, and even 6 hours before bedtime reduced total sleep time by more than one hour. While this is a hefty afternoon, it might be wise to make your caffeine cut-off at 2 pm in the afternoon and stick with a lower dose of caffeine. While more data is needed, you might even be so caffeine sensitive that an afternoon dose of caffeine is not advised at all.