How Sleep Can Help Weight Loss

New "miracle" weight loss remedies seem to surface each week, but the answer might lie in the simple activity we spend a third of our lives doing: sleeping. Find out how bad quality sleep can hinder your weight loss efforts.

Published: Monday 22 March 2021



For many of us, shedding a few pounds has been on the to-do list for a while now, yet it’s an ongoing struggle. It seems simple for the most part: consume fewer calories than you expend, eat a fairly balanced diet and exercise regularly. But unless you’ve got the patience to consistently count every calorie you’re eating, and are disciplined enough to exercise as frequently as maybe is best, losing weight often feels like an uphill battle. Clinically proven weight loss medication such as Alli and Orlos are shown to be effective, but for the best results, it’s also worth assessing how well you’re sleeping. You may be surprised to learn that sleep has just as much of an influence on our weight and well-being as diet and exercise! Despite this, sleep is often a neglected factor of our busy lives, with half of UK adults admitting to not getting enough sleep, and a quarter managing no more than five hours per night[1]. Here in the UK, we average six hours of sleep per night, although the National Sleep Foundation recommends seven to nine hours of sleep is optimal[2].

This article uncovers the considerable impact sleep can have on your weight, suggesting methods to improve your shut-eye.

What’s the Link?

Sleep plays an undeniably important role in healthy bodily functioning and mental wellbeing. Epidemiological evidence suggests that whilst rates of obesity have been increasing over the past 50 years, our sleep duration and self-reported quality of sleep has decreased[3]. Multiple studies have indicated a likely causal relationship between poor sleep and higher rates of weight gain, with numerous explanations proving poignant. Research that has investigated sleep deficit demonstrates an increased likelihood of developing metabolic disorders, gaining weight, and an increased risk of other chronic health conditions. Whilst further research is needed to fully understand the intricate connection between sleep and weight, a number of theories provide convincing evidence.

How Sleep Affects your Weight

Appetite

You’d be forgiven for thinking that succumbing to food cravings is ultimately just a mental weakness, something that fit and healthy people still experience but choose not to act upon. Far more than simply a mindset, evidence indicates that those getting plenty of sleep may not have nearly as big an appetite as those deprived of a full night’s sleep. The neurotransmitters ghrelin and leptin are key to dictating appetite: ghrelin stimulates the appetite, whilst leptin suppresses it. Throughout the day, our bodies produce these neurotransmitters in various quantities to signal when we ought to consume more calories. Sleep helps to sufficiently regulate these neurochemicals, with research finding higher levels of ghrelin and lower leptin levels in sleep-deprived individuals getting fewer than the recommended hours of sleep per night[4]. Therefore, if you struggle to get in seven to nine hours of sleep, you’re likely to have a larger appetite and not feel as satiated as healthy sleepers.

Food Choices

Irrespective of our altered levels of hunger-signalling hormones depending on sleep duration, we may be choosing to consume more calories following a bad night’s sleep. One study found that participants in a sleep-deprived test group were more likely to select snacks that contained 50% more calories than the group that had a full night’s sleep, as well as being drawn towards high carbohydrate foods. Additionally, the test group were less likely to be able to resist high calories snacks like ice cream and cookies, despite having eaten a large meal only two hours prior[5]. Similarly, another study found late-night snacking increased in those starved of a good night’s sleep[6]. The suggestion here is that the lack of a good night’s sleep is likely to affect our ability to make healthy choices the following day, making it that much harder to resist temptation and say no to calorie-dense foods, which contribute to weight gain. This is a particularly important factor in reducing obesity in children and adolescents, who may be less concerned with dieting, and where high-quality sleep is vital during this crucial stage of their development.

Metabolism and Insulin

When we don’t get enough sleep, we experience a spike in the stress hormone cortisol, which triggers the conservation of energy meaning we store more fat. One study found that when they decreased the sleep of their experimental group over a two week period, the weight they lost from fat reduced by 55%, even though their calorie intake didn’t change[7]. As well as increased hunger and a depletion of energy levels, their base metabolism declined, a greater proportion of the calories they were consuming were not being used for necessary bodily functions but instead were being stored as fat. With a lack of sleep, our body finds it more difficult to process insulin, the hormone needed to convert sugar, starches and other foods into energy. A reduction in insulin sensitivity means your body won’t be able to properly process fats from the bloodstream, again leading to more fat being stored.

Physical activity

Following a sleep-deprived night, we’re far less likely to engage in physical exercise the following day, due to feeling like we have less energy and a reduction in our motivation. Not only this, but being tired when engaging in sports becomes less safe, negatively affecting balance and ability to concentrate (especially key for activities such as weightlifting). Not only is exercise key to keeping us healthy and expending calories, but it helps speed up our metabolism, reducing the likelihood of excess calorie intake.

Tips for Quality Sleep To Aid Weight Loss

We’re all well aware of the importance of sleep, but it’s easy for our hectic schedules and the temptation of social media to throw a spanner in the works. Here are our top tips for getting a plentiful night’s sleep: