Sleep – you know you need it, but are you getting enough of it? Many people aren’t, and the problem of too little sleep is on the rise. According to the Centers for Disease Control and Prevention, one out of three individuals in the U.S. gets less than seven hours of sleep per night. We’re falling short! The recommendation is that Americans get 7 to 8 hours of sleep per night.
What happens when you don’t sleep long enough? For one, you feel tired. Skimping on sleep also makes you less productive. More concerning, if you’re significantly sleep deprived, you’re at higher risk of accidents. In fact, a study showed that being deprived of sleep has some of the same effects as drinking too much alcohol. But, there’s another problem. Inadequate sleep also increases the risk of weight gain. Have you ever wondered why? Here’s what happens when you don’t get enough sleep.
You Snack More
Studies show that people snack more when they don’t sleep enough. Snacking, in and of itself, doesn’t necessarily lead to weight gain. In fact, a study published in Harvard Health found that snacking frequency and the timing of snacks doesn’t impact body mass index or weight gain. It’s what you snack on that has the greatest impact. Your body responds differently to a bag of potato chips than it does a bowl of broccoli!
In fact, snacking on fruits or vegetables is a positive because they’re low in calories and nutrient dense. Eating these foods is an ideal way to satiate a desire to munch on something that doesn’t contribute to weight gain. But, there’s a caveat! If you’re sleep deprived, you’re more likely to choose snacks higher in sugar or fat over healthier fare. So, snacking more works against you if you make the wrong snack choices – and when you’re sleepy, you’re more likely to do that.
You Eat More Total Calories Causing Weight Gain
Studies show we eat more total calories when we don’t sleep enough. A small study looked at 17 healthy guys and gals and the impact sleeping less had on their calorie intake. In the study, the participants were allowed to eat as much as they wanted. One group slept their normal sleep schedule while the other slumbered 2/3 of the time they normally slept. On average, they slept 1 hour and 20 minutes less than the first group.
Did the sleep-deprived group consume more calories? Yes! In fact, they consumed an average of 549 more calories relative to the group that slept normally.
Hedonic Eating Becomes a Problem
What is a hedonic eating pattern? It’s eating for pleasure rather than for hunger and it usually involves making less than healthy food choice. Why do we eat more pleasure foods when we don’t sleep enough? A study published in the journal Sleep found that sleep deprivation turns on endocannabinoid pathways, pathways that enhance the desire to eat for pleasure. In fact, these are the same pathways that marijuana acts on and a common side effect of marijuana use is the “munchies.” When the endocannabinoid pathway is ramped up, the desire to snack on sugary and fatty foods for pleasure is too. In other words, you crave unhealthy fare, like doughnuts and ice cream when you don’t get adequate sleep. In the study, sleep-deprived subjects were hungrier and when they had access to snacks, they ate twice as much fat.
What Causes These Changes?
We mentioned how the endocannabinoid pathways are stimulated by lack of sleep. However, lack of sleep leads to an imbalance in two important appetite hormones, leptin, and ghrelin. Ghrelin is a hormone produced by cells in the lining of your stomach that increases appetite. In response to ghrelin, your stomach starts rumbling and you make a beeline for the refrigerator. Leptin is produced by fat cells. When leptin rises, it’s a signal that fat stores are adequate. This is followed by a decrease in appetite.
When you don’t get adequate sleep, ghrelin-making cells go into overdrive, thereby stimulating your appetite, and leptin falls, providing another boost to your appetite. So, the combination of leptin and ghrelin “misbehaving” creates a double whammy that ramps up your desire to eat! So, leptin, ghrelin, and the endocannabinoid pathways are responsible for most of the boost in hunger you get when you don’t sleep enough.
But, it’s also possible that we eat more because we’re sleeping less and have more hours to eat. If you only sleep for five hours, you have three additional hours to munch on unhealthy food items. Plus, sometimes people don’t sleep enough because they’re stressed out. Stress can cause an increase in appetite due to the effects of cortisol.
The Take-Home Message?
Make sure you’re getting enough sleep, at least 7 hours per night. Skimping on sleep will lower your energy level and productivity but it also increases the risk of weight gain. Whether consciously or unconsciously, you’re likely to be hungrier, snack more, nibble on the wrong stuff, and consume a greater number of calories. Also, if you’re sleep deprived, you feel less like working out! Sometimes, we emphasize nutrition and exercise but forget about the importance of sleep. It matters!
Lack of sleep is also associated with other risks. In one study, people who were deprived of sleep performed as poorly as those who were drunk on a driving simulation test. Being sleepy impacts your reaction time as well as hand-eye coordination. That can be hazardous to your health! So, make sleep a priority, just as you do eating a healthy diet and staying active. It all matters!
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