If you are being kept up at night due to stress, working late or engaging in social media in the evening, such habits can creep into our sleep time. Sleep is an often overlooked factor in weight management as the focus is usually on nutrition and exercise. However, it’s important that we understand how this continuing pattern of reduced sleep can slowly but gradually impact our weight.
Many studies, as reported by Harvard University, have shown a convincing association between too little sleep and increased weight, or an increased risk of obesity due to lack of sleep. This has been found in children and adults.
Let’s explore the factors that contribute to these findings.
Studies show that people with lack of sleep take in more calories.
As the Sleep Station explains, insufficient sleep can lead to an increase in the “hunger hormone” ghrelin and a decrease in the leptin hormone that sends the message to the body that it is satiated. Both factors lead to an increase in hunger and in eating to feel satiated.
In addition, those who stay up late may be snacking more in those hours they are awake.
Finally, a sleep deprived mind means there is reduced activity in the pre-frontal cortex, the brain area responsible for self control. This can lead to loss of willpower, and to reaching for quick, easy and unhealthy food choices, those high in calories, to give us an energy hit.
On the other hand, sleep deprivation can lead to increased activity in other areas of the brain such as the amygdala, which is important for the processing of emotions. The Sleep Station explains that this means that when sleep deprived, the brain becomes more responsive to things perceived as pleasing and rewarding, such as eating sweets or fatty satisfying foods.
The UChicago Sleep Center at the University of Chicago Medicine reports that the current obesity epidemic is mostly explained by an increase in caloric intake, rather than lack of exercise. This is important, given the effect sleep can have on calories consumed, as demonstrated by their recent randomized clinical trial with 80 adults, published in JAMA Internal Medicine. It revealed that an extension of sleep time led to a decrease in calories consumed, by an average of 270 calories per day. This was without making any other lifestyle changes. It would roughly equate to 12 kg of weight loss over three years if the effects were maintained over a long term.
The study concluded that you could extend your sleep and eat fewer calories, and that if healthy sleep habits are maintained long term, this would lead to clinically important weight loss over time.
Studies have found that poor sleep may lead to lower physical activity levels. Being tired and less energy makes it harder to exercise.
Weight loss occurs when energy expenditure exceeds energy intake. When you consider that sleep deprivation leads to increase in calorie intake and lower levels of physical activity, this makes an unhealthy equation for weight loss.
Maintaining a healthy weight through improvements can also help to prevent health conditions that are linked to overweight.
If you can identify and acknowledge that there is room for improvement in your sleep habits, then the good news is that you can turn this around, by focusing on taking control of your sleep. The UChicago Sleep Center clinical trial found that just one sleep counselling session was able to improve participants’ bedtime habits, with an increase in sleep duration. The session simply involved coaching them on optimal sleep hygiene, including a discussion about their personal sleep environments, and providing tailored advice on changes they could make to improve their sleep duration.
Though the study did not assess factors that may have influenced sleep behaviour, the findings revealed that limiting the use of electronic devices before bedtime appeared as a key intervention.
Here are some other sleep hygiene tips to help support healthy weight.