An Amino Acid Found in Green Tea Might Help You Sleep For something as essential as sleep, it’s surprising how elusive a good night’s rest can be. Tossing, turning, watching the clock tick past midnight—it’s a frustrating experience that far too many of us know all too well. In fact, roughly 30% of people worldwide struggle with sleep issues, and the consequences go far beyond dark circles under your eyes. Sleep problems can increase the risk of heart disease, diabetes, depression, and even neurodegenerative disorders like Parkinson’s and Alzheimer’s.