It’s 2 a.m. You’ve been asleep for a few hours, but, suddenly, you wake up hungry and desperate for a snack (at least), so you head to the kitchen. Nearly everyone is familiar with this scenario as a once-in-a-while thing, but what about when this is what almost every night looks like?
If getting out of bed to eat has become a habit for you and you’re not sure why that might be, hello and welcome—especially if you’re reading this article on your phone in the kitchen with a fork in the other hand. Let’s see if any of the very many reasons for sleep-interrupting eating feel familiar to you—and what you can do about it.
Typically, our bodies know that sleeping and eating don’t go hand in hand. When we fall asleep, our bodies produce higher levels of leptin, a hormone that suppresses appetite, and when we wake up, production of the hormone ghrelin ramps up and tells our body it’s time to eat.
If your middle-of-the-night snacking is a random one-off, it’s probably because you did something different that day—maybe you had a huge workout and burned through a lot of caloric energy or your regular sleep cycle was disrupted by drinking too much alcohol or pulling an all-nighter. Anything that generally messes with your sleep schedule can also cause you to wake up hungry in the middle of the night.
If you find yourself waking up hungry during the night at least a couple times a week, there’s probably something else going on. Scientists say this pattern of eating, called nocturnal ingestions, is much more common than you’d think. The highest rates are seen in people with obesity, substance use issues, and psychiatric conditions, and estimates suggest about 1.5 percent of the general population suffers from severe, chronic nocturnal ingestions that can be classified as a disorder called night eating syndrome.
The bulk of nocturnal eating episodes is probably massively underreported, experts say, so the true prevalence is likely much, much higher. On top of that, nighttime eating behaviors are generally understudied at the moment, as they’re not exactly the National Institutes of Health’s main priority right now. While scientists have gleaned some valuable insights about why we wake up in the night ready to eat (hint: it’s probably stress), progress with newer studies has been slow—but here’s what experts do know about nocturnal ingestions.
Nicole Avena, a research neuroscientist who focuses on nutrition, diet, and addiction, said patterns of nocturnal ingestion tends to occur when people start fasting or otherwise dramatically reduce their food intake. “They bring their calorie intake down so low during the day, and then they end up having their whole circadian rhythm thrown off,” said Avena. “They can’t sustain themselves through the night, so their body just naturally awakens.” The nocturnal cravings typically subside once their body adjusts to the diet.
There’s also a notable crossover between nighttime eaters and people with diagnosed eating disorders. One study found that 51 percent of people with bulimia and about 35 percent of people with anorexia are prone to nocturnal ingestions. The reason, according to Allison, is that their basic “energy needs aren’t being met.” In addition, people’s thinking is more flexible during the night, so where someone might be concerned about what they consume during the day, those inhibitions tend to loosen up when grogginess sets in overnight.
But Kelly Allison, a professor of psychology in psychiatry at the Perelman School of Medicine at the University of Pennsylvania, says it’s most often not physical hunger that drives someone to wake up ravenous in the middle of the night. Nighttime eating can also sometimes be traced back to a stressful event. (Like, say, a global pandemic.) Through her research, Allison has found that about three-fourths of people who regularly engage in nocturnal ingestions experienced some kind of stressful event that threw off their sleep schedule and made midnight snacking seem enticing.
Other evidence suggests people diagnosed with depression and anxiety are more prone to nocturnal eating. “Any type of mood disorder can put people at risk for developing this type of night awakening and eating,” said Avena.
Emotional eating can be a powerful stress-reliever, at least in the short-term. Instead of sitting in bed mulling over anxiety-provoking thoughts that disrupt sleep, people often turn to food as a sleep aid. “It can certainly slow down your thought processes—if your body is digesting food, then maybe you’re distracted from the anxiety that’s keeping you awake,” Allison said. “It is, unfortunately, an effective way to deflect those kinds of thoughts and focus on the eating.” Once people start using food to get back to sleep, Allison said, they may get sucked into a cycle in which they routinely feel like they won’t be able to fall back asleep unless they eat, and their body also starts to expect food on that schedule.
If you’re like, OK—but I’m eating enough during the day and generally feel fine, and I’m still waking up to eat, you’re not alone. According to Allison, about a fourth of people who wake up hungry aren’t able to identify a root cause. It could be a genetic predisposition, said Allison, but researchers haven’t yet identified a specific gene that’s responsible. If someone has a family member who also wakes up and eats, that’s a clue it could be genetic, said Allison.
While sporadically snacking in the wee hours isn’t going to do much harm, consistently doing so can lead to a host of health issues. Nocturnal snackers often restrict how much they eat the next morning. Some overexercise. Their sleep is disturbed and they’re more likely to stir during the night, contributing to low moods that generally worsen throughout the next day, explained Allison—which, in itself, can help perpetuate patterns of late-night eating. Frequent nighttime eating can also impair cholesterol and insulin levels over time.
There are interventions that can help break the cycle of taking your meals in the middle of the night. Allison suggests substituting eating with another activity—playing some music, meditating, reading a book, or watching TV reruns. In extreme cases, experts recommend locking food cabinets during sleeping hours.
Trying to avoid waking up isn’t usually a person’s best bet, as over-the-counter drugs like melatonin could actually do more harm than good: They may help people fall asleep, but they aren’t great at keeping people asleep. In fact, with melatonin, people may wake up even groggier during the night and have even less control over whether they choose to eat, explained Allison.
If none of that is enough to keep you away from your refrigerator when you’d rather be resting, your best bet is to ask a medical professional what the reason could be. “If you’re having this happen to you, it’s a very good idea to consult with your physician because there could be some other underlying cause that we’re just not aware of,” Avena said. Waking up to eat isn’t a huge deal on its own if it doesn’t happen that frequently—but if you’re finding that a regular mealtime for you is 4 in the morning, it’s time to check in with your doctor.
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