While a few sleepless nights won’t automatically lead to weight gain, experts say consistently poor sleep may contribute to increased belly fat over time. From triggering hunger and cravings to affecting stress hormones and making us less inclined to exercise, here’s why sleep and belly fat can be linked – and what you can do to help yourself.
Whilst poor sleep is very common, many people may not know that it can (unfortunately!) contribute to belly fat for a number of reasons. Not the best news you want to hear considering bad sleep is a nightmare in itself so to add in a double whammy of the link to belly fat, is hardly what we need (yes, I’m a bad sleeper!). That said, to provide a bit of reassurance, it doesn’t mean that a few bad nights will automatically cause belly fat; there are other factors that can also play into it.
Body fat distribution
“Body fat distribution is influenced by many things including genetics, hormones, age, diet and activity,” explained Nikkii Behrens, a nutritionist, sleep specialist and pilates teacher at Rare Pilates
“However, the bad news for poor sleepers is that consistently sleeping too little can create an environment that makes weight gain, including increased abdominal fat, more likely.
“Research has linked short sleep with increased calorie intake and changes in abdominal and visceral fat. One reason is that sleep affects several systems involved in appetite, stress, blood sugar regulation and decision-making around food.”
She explains this is because when we are sleep-deprived, the body can become much more focused on finding quick sources of energy. We may feel hungrier and find highly palatable foods, particularly sugary, fatty or carbohydrate-rich foods, more appealing.
Sleep loss and cortisol
“Sleep loss can disrupt normal appetite regulation and may alter hormones and signalling involved in hunger and fullness. It can also affect insulin sensitivity, meaning the body may not handle glucose as efficiently,” pointed out Nikkii.
“Cortisol is another piece of the puzzle. Poor or insufficient sleep can disrupt our normal stress response and cortisol rhythm. Chronically elevated or poorly regulated stress, alongside other lifestyle factors, has been associated with greater abdominal fat accumulation.
“There is also a very practical explanation: when you are exhausted, you’re often less inclined to exercise, prepare a balanced meal or make the food choices you might make when rested. So the effect of poor sleep can accumulate through both physiology and behaviour.”
In agreement with Nikkii Behrens is Dr. Muhammad Qasim, a medical writer at My Sleep Apnea and a pulmonologist with over 10 years of clinical experience in sleep-related breathing disorders and sleep health.
Why sleeping too little is associated with belly weight gain
“Poor sleep is common, but I would not say belly fat is caused by lack of sleep alone. Regularly sleeping too little is associated with greater weight gain and more abdominal fat, partly because sleep loss changes appetite, food choices, metabolism, and activity levels,” Dr Qasim explained.
“Abdominal fat usually develops from several factors working together, including calorie intake, genetics, hormones, activity levels, age, and sleep. Sleep deprivation can increase hunger and cravings while altering hormones involved in appetite and stress, which may make weight gain around the abdomen more likely over time.
“When we are sleep deprived, the brain tends to become more responsive to rewarding, high-calorie foods, and people often eat more the next day. Poor sleep can also impair insulin sensitivity and increase stress-system activity. On top of that, tired people may simply have less energy to exercise.”
How much sleep is generally enough to support healthy weight regulation?
According to Nikki, for most adults, around seven to nine hours per night is a useful target. “But sleep quality and consistency matter too. Seven or eight hours of fragmented sleep may not leave you feeling as restored as good-quality, continuous sleep,” she explained.
“Rather than obsessing over a perfect number, I encourage women to look at how they feel during the day. If you’re regularly waking unrefreshed, relying heavily on caffeine, struggling with daytime sleepiness or experiencing strong cravings when tired, your sleep may need more attention.”
Advice on how to get better sleep
For those of you concerned about not getting enough sleep, Dr Qasim advises the following:
“Try and keep a regular wake time, get morning daylight, limit late caffeine and alcohol, and create a consistent wind-down routine. If you get enough hours but remain exhausted, particularly with loud snoring or gasping, it is worth being assessed for sleep apnea.”
Regular movement is also something to incorporate into your day.
“You don’t need an intense workout every day, walking, pilates, yoga and strength training can all form part of a lifestyle that supports better sleep,” added Nikki Behrans. And be mindful of what you eat before bedtime.
“Try not to eat a very large, heavy meal immediately before bed, particularly if you’re prone to reflux or digestive discomfort. Equally, going to bed genuinely hungry can make sleep difficult, so a small snack can be completely appropriate. Something like Greek yoghurt with berries, a banana with a little nut butter, or oats can be a good option.”
Other ways to try and help you sleep
Finally, Dr Lucy Hooper, private GP and co-founder of Coyne Medical suggests other things to try if you are finding it hard to get some shut eye.
“We have seen some really interesting scientific data, with one study showing that just 14 days of restricting people’s sleep led to them eating around an extra 300 calories per day. They gained about half a kilogram in weight and had an 11% increase in their visceral fat. “So poor sleep is not just a feeling-tired problem. It certainly can have significant effects on our health and metabolism. But we can’t blame one bad night’s sleep for this. It’s much more about our regular habits over time.
“We know that people who regularly sleep for less than six hours are at higher risk of metabolic problems, and studies suggest they may also tend to eat more calories and gain more weight over time.
“To help improve sleep, most of us know the basic sleep hygiene advice now: avoiding screens before bed, keeping the bedroom cool, dark and quiet, and being aware of caffeine. Some people are particularly caffeine sensitive, so it may help to finish caffeinated drinks earlier in the day, and remember that this includes lots of teas as well as coffee.
“Lying awake worrying about sleep, though, is one of the worst things you can do. Try to look at the bigger picture, focus on small steps and think about what you can realistically improve. If waking very early in the morning is a problem, I sometimes actually suggest shifting bedtime slightly later for a while. That can help consolidate sleep and, for some people, reset their sleep pattern.”
