7 surprising things we learned from sleep researchers

When it comes to new parenthood, feeling perpetually and outrageously tired is a universal truth. If you’ve ever put the milk carton away with the coffee mugs or forgotten where you stashed your car keys while holding them in your hand, you’re in good company. And as all moms and dads know, the sleep deprivation doesn’t end with baby’s first birthday. Travel, changes in routine and growth spurts can all spark sleep regressions at different ages and stages. At this point, you might fancy yourself an expert on exhaustion, but there are actually researchers who study this for a living. Read on for seven surprising things we’ve learned from sleep researchers.

1. You’ll lose about 21 days’ worth of sleep by baby’s first birthday New moms and dads are missing out on a lot of sleep, says Kelly Sullivan, an assistant professor of epidemiology at the Jiann-Ping Hsu College of Public Health at Georgia Southern University, who studies sleep deprivation in parents. “Previous studies have examined the sleep loss associated with having an infant and determined that parents lose an average of two hours of sleep per night for the first five months [of] and then one hour a night until age two,” she says. That adds up to a lot of lost shuteye. And if you have more than one child, the toll is even greater. “In one study, we found that each child in the household was associated with a nearly 50 percent increase in a woman’s odds of insufficient sleep,” she says.

2. You can’t actually catch up on lost sleep It may be possible to make up for one night of tossing and turning by sleeping in the next morning or going to bed a little earlier the next night, but chronic sleep loss is impossible to recoup, says Stuart Fogel, director of the University of Ottawa’s Sleep Research Laboratory. That’s why it’s so important to catch as many zzzs as you can every day. “There’s such a thing as sleep debt, where if night after night you’re not getting enough sleep, you’re never going to catch up,” he says. “That’s why chronic sleep loss is very problematic.”

3. Sleep deprivation messes with your health An ongoing sleep debt can put you at an increased risk of depression, anxiety and weight gain, but the effects of chronic sleep loss don’t end there. “There are strong links with cardiovascular health,” says Fogel. Lack of sleep also messes with the brain’s regulation of hormones that manage a number of important functions, including fighting cancer cells, he says. “Sleep is so important for a wide range of physical and mental health issues.”

4. Napping helps—if it’s done right That often-touted motherly advice to sleep when the baby sleeps is actually what the experts recommend, too. “A mid-afternoon 30-minute nap has been shown to immediately improve short-term memory and alertness following a night of shortened sleep,” says Sullivan. But, there are a few rules for effective naps: Keep them short (no more than a half-hour) and light (snooze with the curtains open to let in some light, or on the couch instead of in your bed, to avoid associations with nighttime sleep, which will lead to deeper dozing). “Waking from a long, deep sleep can actually make some people feel worse,” Fogel says. You may experience what is known as “sleep inertia,” which means you’ll feel extra groggy and slow.

5. Co-sleeping could be making you depressed Sharing a room, or a bed, with your little one means you can avoid the “mombie” walk down the hall in the middle of the night, but as baby gets older, could it be doing more harm than good? One study published in February 2018 in Infant and Child Development found that moms who were bedsharing or room sharing with baby beyond six months were 76 percent more likely to report feeling depressed than those who had already moved baby to their own bedroom.

6. Moms are more tired than dads Women report sleep difficulties about twice as often as men, says Sullivan. Plus, our biology is such that we actually need more hours of solid sleep in order to feel rested. “This becomes particularly relevant for parents at a time when women may have particular challenges with sleep disruption due to the demands of breastfeeding and childcare,” she says. Even with an involved and supportive partner, women are likely to have greater challenges getting enough shuteye. “Biologic processes and hormonal shifts unique to women throughout their menstrual cycle, pregnancy and menopause can affect how well a woman sleeps,” she says.

7. A workout will wake you up! It can be tough to imagine going for a jog (or even a walk) when you can barely keep your eyes open, but sometimes a bit of activity is just what your body needs. Enlist the help of your partner, a family member or a friend to relieve you for a short trip to the gym or studio, or take baby with you to a “mommy and me” class, or go for a brisk walk. “Exercise will help give a burst of endorphins that can not only help parents survive the afternoon fatigue, but is likely to help their sleep at night,” says Sullivan.

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