As board-certified sleep specialist Michael J. Breus, Ph.D., explains to mbg, the circadian rhythm is a roughly 24-hour cycle that your body repeats over and over. “It basically ‘runs’ your sleep—starting it and stopping it—by sending out neurochemical signals telling each area, organ, or receptor site what to produce, what to receive, and what to do,” he explains. And according to naturopathic sleep doctor Catherine Darley, N.D., “There are also clock genes in each cell, which makes the cell do more or less of its function at different times of the day.” Many of our rhythms are dictated by the suprachiasmatic nucleus (SCN), the body’s “central pacemaker” in the hypothalamus of the brain. Environmental factors like lighting entrain this pacemaker, which is why you’ll often hear the advice to seek bright light during the day and darkness at night to maintain a healthy circadian rhythm. Keeping your body clock in sync with the actual clock and its steady cycles of day and night can pay dividends for many aspects of your health, including your sleep. Consider times you’ve been jet-lagged or lost an hour of sleep because of daylight saving. “You get sleepy when you need to be awake, and vice versa,” Breus explains. But the good news is, “The more consistent your sleep schedule, the more ‘aligned’ your rhythm becomes,” he says. And as Breus adds, other lifestyle factors can come into play too, such as drinking alcohol before bed (which negatively affects REM sleep), having too much caffeine during the day, or looking at electronics at night and exposing yourself to blue light. And of course, as anyone who’s ever been stressed before knows, a racing mind isn’t conducive to deep sleep either, so stress can affect your sleep schedule as well. Even fluctuations through a woman’s menstrual cycle can disrupt sleep, Breus notes. Not only does this help you wake up, but as your sleep drive builds throughout the day, it will help you get sleepy at a predictable time each evening. “Waking at an inconsistent time makes it so that a person isn’t predictably sleepy at the same time and can’t sleep as well,” Darley adds. And as far as alcohol goes, Breus previously explained that it takes the average person one hour to digest one drink, so he suggests limiting yourself to two drinks, having a glass of water with each, and stopping drinking at least three hours before bedtime. Consider swapping in a sleep-supporting supplement and some relaxing snacks and beverages instead.* And of course, if you can’t resist the scroll, you can try blue-light-blocking glasses, or turn on your phone’s nighttime setting if it has one.