Why a Lack of Sleep Can Lead to Weight Gain

Health and Wellness | Health Tips

Woman's forehead and eyebrows poking out from under a large white comforter as she sleeps | Lack of sleep and weight gain

Research on Lack of Sleep and Weight Gain

Are you trying to manage your weight? Well, you might consider sleeping more. Mounting evidence shows that more sleep may be the missing link for many people who are trying to lose weight. According to the Centers for Disease Control and Prevention (CDC), 35% of US adults are sleeping fewer than 7 hours most nights which is defined as short sleep. Short sleep, or lack of quality sleep, has been repeatedly linked to higher body mass index (BMI) and weight gain. An analysis of 20 studies including 300,000 people found a 41% increase in obesity risk among adults who slept fewer than 7 hours a night. Another study showed that short sleep duration was significantly associated with greater waist circumference, which is an indicator of the accumulation of belly fat. (1, 2)

Newer research suggests that an extra hour of sleep every night could help sleep deprived people that are overweight consume between 270-500 fewer calories per day without even trying. This translates to nine pounds of weight loss over a year, according to the researchers behind the study. (3) This is significant for people who are trying to manage their weight and believe that weight management is just a product of what they eat and how much they exercise.

An analysis of 20 studies including 300,000 people found a 41% increase in obesity risk among adults who slept fewer than 7 hours a night.

A woman pinches at her browline as if she's tired and has a headache | Lack of sleep and weight gain

Although lack of sleep is one factor associated with weight gain, research suggests it also negatively affects hunger levels and appetite, influencing a person to consume more calories from high fat and high sugar foods.  One review of studies found that those who experienced sleep deprivation consumed an additional 385 calories per day, with a greater than usual proportion of calories coming from fat. (4,5)

The increase in food intake is likely caused partly by the effect of sleep on the hunger hormones ghrelin and leptin. Increasing ghrelin (the hunger hormone) and decreasing leptin  (satiety hormone) may be causing weight gain. When you do not get adequate sleep, the body makes more ghrelin and less leptin, leaving you hungry and increasing your appetite, making it extra hard to lose weight. (6)

Poor sleep may also be negatively affecting the sympathetic nervous system, which can result in increased levels of the stress hormone, cortisol which intensifies your craving for sugar and fat. It can also suppress a hormone called IGF-1 or insulin growth factor 1 which is linked to greater fat storage.

Lack of sleep can also change the way your brain works and can affect decision making. The reward centers of the brain are more stimulated by food when you are sleep deprived. This makes it harder to resist tempting foods. Therefore, after a night of poor sleep, not only is that bowl of ice cream more rewarding, but you’ll likely have a harder time practicing self-control.

A woman stretches and smiles in her bed in bright sunlight as she is waking up for the morning

How Can I Improve My Sleep?

Consider sleeping earlier than you do. This may help you avoid late night snacking which often comes with staying up past your bedtime. What’s more, eating too close to bedtime, especially large meals, may cause acid reflux and indigestion which can also negatively affect sleep quality.

Ideally, try to limit your food intake 2-3 hours before bed. If you’re hungry, consider having a small, protein-rich snack like a Greek yogurt or cottage cheese on a few crackers.

Physical activity can also help with sleep. Sleep and physical activity have a close two-way relationship. A lack of sleep decreases physical activity, and a lack of physical activity may lead to worsened sleep. Numerous studies have shown that regular exercise can decrease the time it takes to fall asleep and increases the overall quality of sleep. Furthermore, a lack of sleep can cause daytime fatigue, making you less interested and motivated to exercise and likely more sedentary which can lead to weight gain.

Try This Tonight:

Try getting to bed at least 30 minutes earlier than you usually do. If you’re not able to sleep, read a book or listen to a podcast or music instead of scrolling through your phone or watching TV which can actually disrupt your sleep.

A woman's hands hold a book propped up on wrinkles of fabric in bed

Bottom Line on Lack of Sleep’s Connection to Weight Gain:

If you’re trying to manage your weight, not getting enough sleep can sabotage your efforts. Poor sleep can lead to poorer food choices, increased hunger and caloric intake, decreased physical activity and possible weight gain.

If you are struggling to manage your weight, it may be time to look closely at your sleep habits. Though individual needs vary, most adults need between 7-9 hours of sleep per night.

Getting some much needed rest can make all the difference in helping you achieve your weight management goals! If you need a helping hand in lifestyle and diet changes for weight management, check out my Weight Management Services. It’s what I do.

Voula Manousos’ writing is featured in the “Winchester Living Magazine” and “The Winchester Star” of Wicked Local.

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