You’re a restless sleeper. You roll over. You change positions. You wake up briefly. Take a look at your personal sleep data on Fitbit, and you’ll likely notice several periods of restlessness during the night.

While it probably sounds like restless nights would lead to tired days, it’s actually perfectly normal to have somewhat restless sleep, says Michael Grandner, PhD, MTR, a Fitbit sleep advisor and director of the Sleep and Health Research Program at the University of Arizona College of Medicine. “Sleep is not completely still,” he insists. “We all move during our sleep, especially in stages 1 and 2—and this is totally normal.” In fact, research confirms it’s typical to have anywhere from 10 to 30 periods of wakefulness or restlessness during the night. 

That said, certain types of restlessness can interfere with sleep quality. “About one third of Americans report that they have difficulty initiating sleep, difficulty resuming sleep when they wake up during the night, or wake up too early and can’t get back to sleep, at least occasionally,” says Grandner. “Sleep problems are very common.”

Let Grandner explain what types of restlessness are A-OK, and which deserve deeper attention.

Although the occasional sleep hiccup is no big deal, there are certain signs you’re not getting enough restful sleep each night. “When you are so restless at night that you wake up feeling exhausted, and normal ‘sleep inertia’ doesn’t wear off after being awake for 15 minutes or so, that is a warning sign,” Grandner says. “Also, if you are spending more than 30 minutes awake at the beginning of the night or in the middle of the night trying to sleep, and this occurs for more than three nights a week and has lasted over three months, then you might meet criteria for a sleep disorder.”

Grandner says that so many underlying conditions and daily issues can cause restless sleep. “In addition to stress and mental worrying, physical discomfort like pain or illness can cause it, as well,” he says. “Many people have sleep-related breathing disorders that never get diagnosed, and they can also lead to restlessness.” Disturbed “zzz” time is also the product of interruptions, like that of noise, light, or movement in your sleeping environment.

Sleep is a necessary and vital part of your overall health and ability to function, says Grandner. Consistent sleep allows the body to recharge and de-stress, the brain to sweep itself clean of toxins (says some emerging research), and will improve your mental clarity and performance throughout the day. Overly restless nights will prevent your body from rebooting properly; sleep issues have been linked to conditions like heart disease and depression. “If you feel like your sleep is restless enough that it’s interfering with your life, you might want to talk to a doctor,” says Grandner.  

If your restlessness is mild, or you haven’t tried to tackle the problem yourself, Grandner suggests a few simple adjustments to your bedtime habits. “Get rid of some obvious barriers to restful sleep,” he says. “Go to sleep at a reasonable time and keep your sleep as regular as possible. Keep your sleeping area as cool, dark, quiet and comfortable as you can. Cut down on caffeine, alcohol, and nicotine in the afternoon or evening.” If none of that works, and you’ve been dealing with tosses and turns for months, call your doc.

That said, don’t panic if you have a bad night or two. “Remember that some amount of restlessness is perfectly normal!” says Grandner. Phew.