Ever since you were a kid, you’ve probably heard how important sleep is. This wasn’t just your parents being a buzzkill — quality sleep supports physical and mental health and impacts your energy, mood, focus, metabolic health, and more. (1) Additionally, good sleep habits are connected to weight management. (2)
If you’re looking to lose weight and curious how important sleep is, keep reading to discover why good sleep is a key piece of the puzzle and how it supports your metabolic health.
Does sleeping help you lose weight?
Sleep doesn’t cause weight loss per se, but it is a critical part of successful weight loss efforts. The optimal amount of sleep for adults varies from person to person, but in general, science says sleeping 7-9 hours per night is needed to support good health. (3)
It’s clear that disrupted sleep patterns contribute to increased calorie intake, poorer food choices, and undesirable changes in metabolism and the hormones that regulate it. (2) Metabolic syndrome and obesity are also associated with disrupted sleep patterns; research shows adults who consistently sleep less than 6 hours per night weigh more and have a higher body mass index (BMI). (4)
The underlying connection between sleep and weight loss centers around metabolism. Below, we explain the science and provide tips for optimizing sleep for your health goals.
The sleep-metabolism-weight connection
Circadian rhythm is your “internal clock” that regulates your sleep-wake cycle, but did you know it also affects many physiological processes including glucose and fat metabolism? (5) During the daytime when the sun is up and you’re awake, your metabolic rate is churning and kicks into high gear after each meal, which raises body temperature slightly.
Conversely at night in order to sleep, your body temperature lowers, and since you’re in a post-absorptive state (meaning you haven’t eaten in a while), your metabolism isn’t revved up.
If any part of this pattern is disrupted, such as staying awake for extended periods, sleeping less than 7 hours, being awake late into the night or overnight (e.g. shift work), or consuming food during nighttime hours, your circadian alignment will be thrown off.
Your metabolism isn’t geared towards processing food efficiently at night when it should be sleeping. Eating late at night, especially sugary or carb-rich foods this time of night when cells are more insulin resistant, causes higher and more variable glucose levels, and storage of calories as fat. (6) Without adequate down time, normal restorative processes are disrupted, which over time can wreak havoc on your metabolic health and weight loss goals.
How sleep can support weight loss
Adequate sleep allows proper functioning of your appetite hormones. Short sleep duration increases ghrelin (hunger hormone) and decreases leptin (satiety hormone), (7) not the combo you need when you’re awake longer and have more opportunity to eat. Studies show it’s not vegetables and protein that you’ll reach for when you haven’t slept enough, but rather ultra-processed, calorie-dense foods. (8)
A good night’s sleep promotes daytime energy levels, making you more likely to be energized to work out. Exercise helps with weight loss as it increases the number of calories you burn in a day, helping to create a negative energy balance and gradual weight loss over time. Strength training specifically helps build muscle, which burns more calories at rest.
Sleep stages are important for rest and recovery from exercise, allowing your body to get stronger and improve body composition: build muscle and burn fat. The body’s natural production and secretion of growth hormone, which is responsible for supporting healthy muscle and burning fat, occurs just after sleep onset and continues to rise during the first 4 hours of sleep. This becomes blunted without enough sleep. (9)
Even if over time your total body weight on the scale doesn’t change much, eating right, strength training, and adequate sleep can help you lean out and have favorable changes to your body composition.
Sleep tips for your weight loss journey
Aim to spend more time in bed than you hope to sleep. Not everyone dozes off as soon as their head hits the pillow. This means if you got into bed at 11 p.m. and woke up at 6 a.m., you probably weren’t asleep the full 7 hours. Consider keeping a sleep journal or using an app or wearable device that can paint a slightly more accurate picture of your actual sleep time. Documentation can help keep sleep time a priority and top of mind.
Consistency is key. Social jetlag refers to sleep and wake times varying more than 2 hours day to day and is associated with greater weight gain over time. (10) In reality, you will stay up later some nights, but try not to make varying sleep and wake times greater than 2 hours a habit. Consistent mealtimes can help anchor this habit and provide stable energy and physiological cues that it’s time to be awake, eat, or rest and sleep. The body thrives on routine.
Awake at night? Go low carb. Research suggests that shift workers who follow a low-carb, ketogenic diet may protect themselves against some of the adverse consequences of consuming calories at suboptimal circadian phases. (11) Restricting carbohydrate intake can help create a calorie deficit for weight loss, as well as reduce fasting and postprandial glucose, both of which are linked to numerous chronic diseases.
Schedule an early dinnertime. Eating too close to bedtime, especially if it’s a particularly large or high-carb meal, can inhibit processes that help your body get to sleep and stay asleep. Early time-restricted eating, for example only eating meals between 10 a.m. and 6 p.m., is a proven method to successfully reduce daily calorie intake to facilitate gradual weight loss over time. (12)
Give yourself a caffeine curfew. If you need a pick-me-up in the afternoon, instead of reaching for coffee or an energy drink, try having a snack with protein and healthy fats. This choice not only supports stable glucose levels and sustained energy, but also promotes satiety, potentially aiding in portion control during dinner and helping you stay within your daily calorie budget.
Limit alcohol. Alcohol has 7 calories per gram (in addition to calories in mixers), lowers inhibitions, and disrupts sleep quality — all things that can derail your weight loss goals. While you may have experienced that alcohol helps you fall asleep, it tanks sleep quality and reduces time in each sleep stage. Effects carry over to the next day when you’re feeling hungover and tend to reach for ultra-processed foods, which are high in added sugars, salt, and fat. All of this can derail your weight loss plan.
A final note from Lingo
When you’re putting in the extra effort with your nutrition and exercise to lose weight and keep it off, make sure you’re not overlooking sleep. Reaching your weight loss goals takes a holistic approach that considers many lifestyle factors including nutrition, exercise, stress, and sleep. Insights into your metabolism with a continuous glucose monitor like Lingo can help keep your diet and sleep habits on track.