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In today’s fast-paced world, it’s all too easy to sacrifice sleep for late-night TV, social media, or a last-minute work call. But catching some zzz’s is more than just downtime – it’s a crucial component of health. In fact, research links sleep loss with serious health risks like heart disease, dementia, diabetes, and even obesity. If you’re looking to optimize both your well-being and weight, prioritizing sleep is essential.
In this article, we’ll delve into the role of sleep in weight management, exploring its effects on eating habits and physical activity. We’ll also provide science-backed strategies to improve sleep quality and counteract the consequences of a poor night’s sleep.
How sleep affects weight management
Managing your weight boils down to balancing the energy you take in with the energy you expend. To shed pounds, you’ll have to consume fewer calories than you burn. Although this “calories in vs. calories out” concept sounds simple, many factors influence both sides of the equation. And one major factor? Sleep.
Getting a good night’s sleep makes it easier to stick to your diet. On the flip side, inadequate sleep can increase energy intake. A 2019 meta-analysis by Zhu and colleagues revealed that those who slept under 5.5 hours nightly ate an additional 252 calories per day compared to their well-rested counterparts. Sleep loss tends to spur snacking and bigger portion sizes, likely due to changes in appetite and self-control.
It’s challenging to keep calorie intake low when hunger is high. Sleep deprivation exacerbates this issue by boosting both appetite and hunger levels. Some research finds that poor sleep lowers leptin, a hormone that signals fullness, and increases ghrelin, which stimulates hunger. These hormonal shifts can leave you feeling hungrier and less satisfied after eating.
Skimping on sleep weakens self-control, making it harder to rein in your cravings. When you’re sleep-deprived, brain areas that process reward become more active, especially in response to tempting, high-calorie foods. Meanwhile, brain regions responsible for self-control and decision-making show reduced activity. As a result, you’re more likely to act on impulse and succumb to temptation despite your dietary goals.
Sleep influences energy expenditure by affecting physical activity levels, both during workouts and throughout the rest of your day. This cumulative reduction in activity can lead to lower overall energy expenditure, impacting your calorie balance and weight.
Quality sleep supports athletic performance, with research suggesting that upwards of 10 hours in bed offers additional benefits. Conversely, lack of sleep makes workouts feel harder and hampers your ability to push through long training sessions. Even a single night of poor sleep can hinder performance – particularly when workouts are done long after waking. While this effect holds up across various exercise modalities, some studies suggest speed, endurance, and strength in compound movements suffer the most.
During sleep, our bodies undergo physiological changes essential for tissue repair and recovery. If these processes are cut short, it can be challenging to grind workout after workout. For example, Skein and colleagues observed that sleep deprivation reduced post-workout recovery of muscle glycogen – the primary fuel source for muscles – and impaired performance in subsequent workouts. Other research shows similar performance decrements over time, greater sleepiness, and less motivation to train.
Poor sleep also heightens the risk of injury, which can further impede your progress and affect energy expenditure. In fact, Grier and colleagues discovered that sleeping 4 hours or less per night more than doubled the risk of injury.
The most variable component of our total daily energy expenditure (TDEE) comes from incidental movements throughout the day. Poor sleep can reduce these spontaneous activities. Research finds that individuals getting 4 hours of sleep engaged in less physical activity during the day and fewer high-intensity activities compared to those who slept 8 hours. However, a study by Wilms and colleagues suggests this effect is stronger when waking up early rather than staying up late.
The role of sleep in weight management extends beyond energy balance: it also impacts body composition by influencing muscle protein synthesis and fat oxidation. So even if you create a calorie deficit to lose weight, sufficient sleep is key for maximizing fat loss.
Muscle growth and loss depend on the balance between muscle protein synthesis and breakdown. Adequate sleep influences this balance by maintaining healthy levels of hormones like testosterone and insulin-like growth factor 1 (IGF-1), which promote muscle protein synthesis. In contrast, sleep deprivation lowers both of these hormones while increasing cortisol, a stress hormone that blocks protein synthesis. These changes ultimately favor muscle protein breakdown over synthesis, increasing the likelihood of muscle loss.
Our ability to burn and lose fat can also be affected by sleep. For instance, Nedeltcheva and colleagues found that individuals who slept only 5.5 hours a night lost 55% less fat and 60% more lean mass over 14 days compared to when they slept 8.5 hours, even with the same calorie deficit. This reduction in fat loss was accompanied by decreased fat oxidation.
Foods high in tryptophan
Foods high in melatonin
You can also consider taking 1 to 6 mg of melatonin on nights when sleep is a struggle.
Sometimes life can get in the way of quality sleep, whether it’s due to a holiday party or a sick child. If you find yourself recouping after a poor night’s sleep, follow these 10 tips to stay on track toward your health and fitness goals:
The bottom line: prioritize sleep to hit your health goals
Sleep isn’t just a luxury – it’s a necessity if you want to achieve your health and weight goals. Adequate rest makes it easier to stick to your diet, perform at your best, and stay active throughout the day. What’s more, sleep can influence body composition independent of energy balance. So if you’re serious about your weight and well-being, start making more time for quality shuteye.
Want to dive deeper into the science of sleep? Check out this recent video by Dr. Layne Norton, co-founder of Carbon Diet Coach. He breaks down the crucial role sleep plays in your health journey. Watch the video here to see how sleep can supercharge your results!
