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How Lack of Sleep Can Ruin Your Marriage

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A fight with your significant other can do more than just spoil your mood. A new study in the journal Psychoneuroendocrinology suggests it can also raise inflammation levels throughout your body—especially if you skimped on sleep the night before. Researchers say the combo of sleep loss and spousal spats could, in the long run, be bad news for overall health.

Scientists at the Ohio State University knew that people with sleep disorders or serious sleep deprivation have higher levels of inflammation in their bodies—a risk factor for diabetes, cancer, heart disease, and other chronic conditions—than those who sleep normally. So they wanted to find out if just one or two nights of inadequate sleep would temporarily raise inflammation as well.

To do so, they asked 43 married couples to report to their lab for early-morning blood tests. “We expected that people who got less sleep would wake up with higher morning inflammation levels,” says lead author Stephanie Wilson, a postdoctoral researcher at Ohio State’s Institute for Behavioral Medicine Research. “We were a bit surprised to find that that wasn’t the case.”

What the researchers did find, however, was potentially just as troubling. When they asked the couples to “discuss and try to resolve” a contentious issue like money, communication, or in-laws (in other words, they asked them to fight) and then tested their levels again, they found that post-argument inflammation was higher in people who’d lost out on sleep the night before.

In fact, for every hour of sleep lost, participants’ levels of two known inflammatory markers had risen an average of 6 percent. “This suggests that even a modest loss of sleep in the last night or two could increase your risk for increased inflammation to a stressor,” says Wilson.

Even though the research didn’t show a direct link between short sleep duration and inflammation, Wilson adds, “this study lifts the veil on another piece of why sleep is still important.” (A review published in 2016 also found that sleeping less than seven hours a night was not directly associated with higher levels of inflammation.) “Now we know the relationship isn’t that simple,” she says. “It’s when lack of sleep and stress are combined that there’s an increased risk.”

Lack of sleep was also linked to bigger and angrier fights. If both partners got less than seven hours of sleep the previous two nights, their discussions were more likely to become hostile. And that made inflammation even worse: Couples who used unhealthy tactics in their disagreements saw about a 10 percent increase in inflammation for each hour of sleep loss.

The findings are so concerning, the authors say, because lack of sleep and marital conflict are both extremely common in daily life. Case in point: About half the people in the study had slept less than the recommended seven hours in recent nights. According to the Centers for Disease Control and Prevention, about 35 percent of Americans don’t meet this guideline on a regular basis.

Part of the problem, says senior author Janice Kiecolt-Glaser, director of the Institute for Behavioral Medicine Research, is that sleep problems and marital issues often build on each other. “If one person is restless, or has chronic problems, that can impact the other's sleep,” Kiecolt-Glaser said in a press release. “If these problems persist over time, you can get this nasty reverberation within the couple.”

Ideally, she says, people should try to get seven hours of sleep a night—not just for their inflammation levels, but for their overall health and well-being, as well. When that doesn’t happen, though, “being mindful of the way you’re communicating with your spouse could help safeguard against some of the harmful effects."

This article originally appeared on RealSimple.com

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