As a Ph.D. diplomate of the American Board of Sleep Medicine, I’ve devoted 35 years to the study of human sleep and clinical sleep disorders. Here are the drinks I recommend avoiding for better shut-eye—and the beverages that will help your sleep better: Milk, 90 minutes before sleep, may also help you fall asleep (if you’re not lactose intolerant). Whether you warm it up or not is a personal preference—it has no effect on milk’s sleep-inducing properties, which are tied to the essential amino acid L-tryptophan. Water is important to drink throughout the day for optimal health. However, drinking water right up until bedtime will stimulate your kidneys and you’re likely to wake up multiple times in the first few hours of sleep. Some people specifically use alcohol as a sedative. And yes, they fall asleep fast. But once the alcohol has been metabolized—maybe three to four hours into sleep—they abruptly awaken and find it difficult to return to sleep. If they do manage to get back to sleep, the remainder of the night is typically characterized by fitful sleep with frequent awakenings and intense dreaming. The sleeper wakes up groggy, tired, and unrefreshed despite having been in bed for a full seven to eight hours. Nighttime alcohol can also induce snoring in a sleeper who does not normally snore and increases the risk of obstructive sleep apnea. And so the cycle goes: larger and larger amounts of caffeinated coffee at three- to four-hour intervals throughout the day. The problem is that the stimulant effect of caffeine also increases your heart and respiratory rates, making you feel anxious and jittery right up to bedtime. Heavy daily caffeine consumption and caffeinated drinks close to bedtime are very disruptive to falling and staying asleep in most people. Afternoon and nighttime caffeine will also aggravate any restless-leg symptoms you may have. Restless legs are uncomfortable creeping, crawling sensations in your calf muscles when you are sitting or lying still that force you to keep moving your legs. These are the folks who are constantly moving their legs and shifting their positions around during meetings, movies, or plays. Restless-leg symptoms tend to increase over the day and are particularly severe during the evening and at bedtime. If you have restless legs, consider eliminating caffeinated beverages altogether or at least after lunchtime. How to cut down on caffeine: Switch to beverages that are half-caffeinated and half-decaffeinated. Confine your caffeine consumption to mornings up through lunchtime, with only decaffeinated beverages later in the day. Aim for a daily target of 10 to 12 ounces of caffeinated coffee or tea by the end of two weeks.