Good, consistent sleep has a host of benefits: Boosted immunity, reduced stress, easier weight control, better focus and more. But, if it’s typical for you to skimp on sleep all week and then try to “catch up” over the weekend, the bad news is you might not be getting these benefits. Even worse is that playing catch-up with sleep doesn’t really work that way.

Why Can’t I Make Up Lost Sleep on Weekends?

There are a few problems with trying to make up for lost sleep over the weekend. For one, research shows that even one night of poor sleep affects our mental and physical health, and the adverse effects get even worse on days two and three, building what’s known as sleep debt. So by the time the weekend rolls around, you’ve likely already suffered the effects of sleep deprivation: low mood, irritability, impaired focus, aches, stomach issues or other symptoms.

Plus, sleeping inconsistently means you’re upsetting your circadian rhythms, the 24-hour cycles managed by the brain that drive us to eat, sleep and perform other functions most optimally.

“There’s a 24-hour rhythm that governs a whole bunch of things, including when you become naturally sleepy and when you feel naturally wakeful. And you ideally want to sync your actual sleep schedule with that underlying rhythm,” says Dr. Andrew Varga, neuroscientist and physician at The Mount Sinai Integrative Sleep Center. “By having that bedtime and wake time consistency day in and day out, you're going to best sync your sleep times and your sleep schedule to that underlying circadian rhythm.”

Are Inconsistent Sleep Schedules That Bad for You?

Though we have the ability to override the signals we get from our circadian rhythms — you can stay up even when you’re tired, for example — doing so has consequences.

Inconsistent sleep “has multiple downstream effects,” Varga says, noting that it hurts sleep quality, even if you sleep a sufficient number of hours overall. It also affects how we metabolize food, he adds.

“If you have a highly variable bedtime, it tends to mean that you also have a highly variable schedule of doing the other things that you do in your life before sleep,” he says. “One of the big ones is eating. There's evidence suggesting that the circadian timing of eating has important factors to it, that the same meal eaten very late ends up being metabolized differently than the same exact meal eaten earlier. If you eat it at the wrong time, you're more likely to have higher glucose spikes, poor metabolism of things like fatty acids, and so on.”

Research shows that poor sleep negatively affects our metabolic health, putting us at greater risk for type 2 diabetes, obesity and cardiovascular disease, and banking sleep on the weekend doesn’t really help that. “You can help your overall health, including some of these metabolic aspects, by having that consistency to your bedtime,” Varga says.

Additionally, consistent sleep and wake times are one of the clearest indicators of sleep hygiene, meaning that inconsistent bedtimes often indicate poorer sleep hygiene. A recent study by SleepScore Labs found that worse scores in sleep hygiene correlated with less sleep and lower SleepScores, as well as less REM sleep.

How to Set Consistent Sleep/Wake Times

Though the notion of having a uniform bedtime and wake time can seem simple enough — just go to bed and get up at the same times every day — in practice it’s not always that easy, Varga says. Revenge bedtime procrastination, work issues, evening plans (known as social jetlag), and schedule disruptions due to a partner, child or pet can all make it hard to keep to a set schedule.

Here are some techniques he recommends for getting yourself on track:

• Manage light exposure. “The number one thing that really governs your circadian rhythm is light,” Varga says. Getting bright light in your eyes upon waking up is great to get your day started. And shutting off phones, tablets and other devices an hour before bedtime is a good practice for night when trying to wind down light exposure.
• Eat breakfast. “Being consistent with meal timing is important,” he says. “It’s important to eat breakfast. Food is generally wake promoting. When you ingest food, it's sending a signal to the body, telling the body that it's time to be awake. And if you do that day in and day out, you're sending signals to your body that this is the rhythm.” Stopping eating about three hours before bed also tends to be helpful, he adds.
• Work out earlier. “Exercise tends to be generally a wake-promoting activity,” he says. “So we generally tell people that if you're going to exercise, it's best to do it in the morning.” Or, if later in the day is better for you, like eating, try to stop three hours before bed.

Stick to the 30-Minute Rule

Though consistency is important, Varga points out that it won’t always be possible, and that’s OK. “I don't want people to not have a social life, and not do things on the weekends with family and friends, because they're trying to adhere to this,” he says. Aim to keep your sleep and wake times consistent within 30 minutes as often as possible, but don’t let it keep you from living your life.