We can't say it enough: Sleep deprivation is no joke — and disrupted sleep is just as bad. Now, we can safely add consistency to the growing list of your sleep needs. Quality, quantity, and consistency are all key, and according to a new study published in The Endocrine Society, even your heart health depends on a good night's sleep. Related: Can't Sleep? 6 Weird Reasons You're Still Awake The study investigated the effect of "social jet lag" (a condition that occurs when your sleep schedule during the work week varies widely from the one you keep on the weekends) on people's health, using a sample of nearly 450 men and women. Those with the most erratic schedules also had the most indicators of poor health, including high cholesterol and higher blood sugar levels. While these findings were clear overall, researchers also noticed that just one off night could negatively impact these indicators. Related: 11 Tricks To Wake Yourself Up After A Total Lack Of Sleep As the holiday season (and all the events that come with it) rapidly approaches, be sure to honor your health and your sleep schedule — keep it consistent as possible, limit caffeine and screen time, but, you know, still try to hit a few of those parties.