How Sleep Can Affect Your Relationship, According to Science

In a properly functioning body, sleep helps the brain process your emotions and memories from the day. You wake up well-rested with enough mental space to both create and log new memories and work through the experiences of your day.

Sleep deprivation, on the other hand, is like falling into an icy river: “The body shuts down circulation to the appendages and tries to keep the core warm. It goes into survival mode,” says W. Christopher Winter, a neurologist based in Charlottesville, VA and the author of The Sleep Solution. When you’re not sleeping well, “your brain’s ability to do things gets whittled down to: find food, urinate, get through the day,” he says.

That means superfluous activities—like conversations with your partner, social outings or remembering to pick up the dry cleaning—go out the window.

Which is why sleep is more paramount to your relationships than you think. “All of the things it takes to make a relationship work are probably completely decimated by lack of sleep,” says Winter.

Here are three ways sleep impacts relationships—and how to gain the energy to fight back.

Your emotions are thrown out of whack

Ever feel like you just want your partner to get to the point of the story already, or that you’re a little more anxious than usual after an all-nighter? You might just be a bit tired.

When you’re sleep-deprived, the part of your brain that ties emotions to memories—the amygdala—doesn’t function properly, Winter says. That could take form in the amygdala releasing more or less neurotransmitters, which Winter says could lead you to overreact or not notice someone else’s emotions, respectively. In fact, a 2013 study published in the journal Psychosomatic Medicine found that the amygdala activity to stressors in poor sleepers predicted symptoms of depression and perceived stress.

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In short: When we’re deprived of sleep, we’re more likely to overreact to situations that normally wouldn’t rattle us. “This can lead to more conflict and less satisfying relationships,”says Jennifer L. Martin, a clinical psychologist and behavioral sleep medicine specialist at UCLA.

“If you have ever seen a 2-year-old who skipped a nap, you can see a version of how we all react to sleep deprivation in terms of our emotions,” says Martin. “Small problems seem bigger. Our reactions are amplified. Some studies show that people are more likely to feel sad, depressed, or anxious if they don’t sleep well or if they are sleep-deprived.”

Unfortunately, Martin says, this is compounded by the fact that we don’t usually notice this amplification of our emotional reactions.

The next time you find yourself easily irritated, anxious or abrupt, think about how your sleep was for the past few nights. The simple realization that you might be overreacting can help diffuse a situation, Winter says.

Another tip: save the serious conversations for a day when you are more rested. Winter says sleeping better make us less prone to risky behaviors. We make better decisions, tend to be more patient and have a greater ability to listen and concentrate when we’re well rested (all components of a healthy relationship), Winter says.

A lack of sleep can make you sick and tired

Insufficient sleep can put you at a risk for health issues including diabetes, obesity, heart disease, and depression, according to the Centers for Disease Control and Prevention. But other issues stem from insufficient sleep, too—like the common cold, Martin says. And that’s yet another factor that could keep you from being out and about with your partner.

After all, if you’re home sick, your interest in spending time with anyone or anything besides your bed can plummet. “That can have a negative impact on relationships,” says Martin. Over time, missing out on dinners or events because you’re too tired or too sick can wear on a relationship, she says.

And while the common cold is, of course, a smaller scale example, research suggests that, for partners, being a caretaker can be stressful and, specifically for women, negatively impact mental health.

Different sleep schedules can cause relationship problems

If you’re in a relationship and work odd-hour shifts, making plans to see the people who matter to you can be a challenge. After all, it can be difficult to find the time for a cookout if you work evenings while your partner works 9 to 5.

“It’s a rare person who can really nail it regarding a relationship and working unusual hours,” Winter says.

That’s why he suggests sharing a Google Calendar with loved ones. It can help you not only plan ahead, but also remember the arrangements you’ve already made—especially since a lack of sleep can impact memory, Winter says.

But what should you do if your partner has the precarious schedule? Meeting in the middle—staying up a little later or asking a partner to wake a little earlier—can also help to secure more together time, she says.

And perhaps most important, respect his or her need for sleep. “For some reason, couples feel like they can ask their partner to miss out on sleep so they can spend time together,” says Martin. A better bet is to focus on spending quality time together when your partner is most alert. “A 30-minute conversation is likely more important for maintaining a healthy relationship than watching two hours of Netflix,” she says.

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