Your baby doesn’t care that you have work in the morning or that you just spent four nights in a row attending to his nighttime messes, and it’s ruining your health. But at least you’re getting some sleep, you think. After all, it’s better than none. Well, maybe not.
A new first-of-its-kind study from Tel Aviv University has found that interrupted sleep — frequent awakening throughout the night, for 10 to 15 minutes at a time — hurts your overall health to the same degree as getting no sleep at all. New parents aren’t the only ones at risk. Doctors, too, face similar challenges if they’re always on-call, posing serious health risks to patients who need proper care.
"These night wakings could be relatively short,” said study leader Professor Avid Sadeh in a statement, “but they disrupt the natural sleep rhythm. The impact of such night wakings on an individual's daytime alertness, mood, and cognitive abilities had never been studied. Our study is the first to demonstrate seriously deleterious cognitive and emotional effects."
Sadeh and his colleagues equipped 61 healthy adults with wristwatches that monitored whether they were sleeping or awake. Each participant slept one full night for eight hours and one night interrupted every couple hours with a phone call and instructions to complete specific tasks on a computer. Each break lasted around 10 minutes. In the morning subjects reported their feelings of alertness, mood, and cognitive state, along with completing a secondary computer task designed to assess brainpower objectively. After only one night of frequent interruptions, the team says it found a direct link between disrupted sleep and poor health.
"Many previous studies had shown an association, but none had established a causal link,” Sadeh said. “Our study demonstrates that induced night wakings, in otherwise normal individuals, clearly lead to compromised attention and negative mood."
As the TAU professor pointed out, the study only reveals the effects of one night’s worth of interrupted sleep. Babies aren’t considerate enough to give their parents a day off; they demand constant attention. That means night-in and night-out moms and dads are rising in the darkness, sacrificing their own well-being sometimes three to 10 times a night for months on end, just to keep their precious miracle alive and happy.
Interrupted sleep is so damaging because the broken sleep schedule disrupts natural circadian rhythms. These natural patterns of sleep compel us to rise more or less with the sun and sleep when it gets dark. While we’re asleep, our bodies pass through necessary cycles of deep, resting sleep and lighter sleep. If we deprive ourselves of reaching those deep sleep states, our brains never reset, or rest. We feel drained. Our intelligence and emotions suffer.
“Besides the physical effects of interrupted sleep, parents often develop feelings of anger toward their infants and then feel guilty about these negative feelings,” Sadeh said.
Unlike a lot of research that tends to overstate its conclusions, these findings may undersell the true price new parents pay. Sadeh says this offers ample evidence that more research on the subject is needed. Sleep deprivation is a problem in long stretches, but also in the aggregate. “I hope that our study will bring this to the attention of scientists and clinicians, who should recognize the price paid by individuals who have to endure frequent night-wakings."
Source: Kahn M, Fridenson S, Lerer R, Bar-Haim Y, Sadeh A. Effects of one night of induced night-wakings versus sleep restriction on sustained attention and mood: a pilot study. Sleep Medicine. 2014.