Sleep and Weight Loss – Is There a Link?
The recommended sleep duration for adults is seven to nine hours a night, but many people often sleep for less than this. Research has shown that sleeping less than the recommended amount is linked to having greater body fat, an increased risk of obesity, and can also influence how easily you lose weight on a calorie-controlled diet.
Metabolism, Appetite and Sleep
There are several reasons why shorter sleep may be associated with higher body weight and affect weight loss. These include changes in metabolism, appetite and food selection.
Sleep influences two important appetite hormones in our body – leptin and ghrelin. Leptin is a hormone that decreases appetite, so when leptin levels are high we usually feel fuller. On the other hand, ghrelin is a hormone that can stimulate appetite and is often referred to as the “hunger hormone” because it’s thought to be responsible for the feeling of hunger.
One study found that sleep restriction increases levels of ghrelin and decreases leptin. Another study, which included a sample of 1,024 adults, also found that short sleep was associated with higher levels of ghrelin and lower levels of leptin. This combination could increase a person’s appetite, making calorie restriction more difficult to adhere to, and may make a person more likely to overeat.
Consequently, increased food intake due to changes in appetite hormones may result in weight gain. This means that, in the long term, sleep deprivation may lead to weight gain due to these changes in appetite. So getting a good night’s sleep should be prioritised.

Here are five common mistakes a lot of people make (mostly in the morning) that affect their ability to fall asleep — and have good quality sleep.
1. You’re drinking too much caffeine
In general, most healthy adults can safely have up to 400 milligrams of caffeine a day. That’s the equivalent of roughly four cups of brewed coffee or two energy drinks – if that’s your thing. Remember, though: caffeine levels in energy drinks can vary widely, and there are serious concerns about their potential impact on the body.
The effects from caffeine generally kick in within 15 minutes and peak about an hour later.
“Six hours after caffeine is consumed, half of it is still in your body,” according to the Cleveland Clinic. “It can take up to 10 hours to completely clear caffeine from your bloodstream.”
That means you can absolutely have a few cups of coffee in the morning and still be feeling them by dinnertime.
2. You’re waking up at totally different times every day
Why? If you sleep for a few extra hours on a Sunday, for example, you might not be tired again until much later than usual — which means your bedtime is thrown off and you’re likely to be pretty darn tired when you wake up early for work on Monday.
An irregular sleep schedule can also increase your risk of what experts call “social jet lag” — basically, the discrepancy between your body’s natural sleep schedule (i.e., circadian rhythm) and your social schedule, which throws off the midpoint of your sleep and has been linked to health issues such as increased inflammation and higher risk of depression.
On the other hand, there can be benefits to catching up on sleep during the weekends, especially if you have a big sleep debt. To the extent, it’s possible, however, try not to make it a regular thing.
3. You’re not exposing yourself to natural light
Your body’s circadian clock is most sensitive to light starting about two hours before your usual bedtime and lasting throughout the night up until about one hour before your usual wake time.“Exposure to light during these times will affect when your body naturally gets sleepy and is ready to fall asleep.”
What all of this means is that exposing yourself to plenty of bright light in the morning can help shift your bedtime earlier; by the evening, you’re more likely to be sleepy and primed for rest.
4. You’re not thinking on paper
Not all to-do lists are created equal, though. First and foremost, it’s a good idea to write it down. It declutters and decompresses your mind from having to remember so many things.
When you try to manage your to-do list in your head, you’re likely to forget items. Jotting it down on paper (or digitally in your Notes or another mobile app, if you prefer) gives you something concrete to refer to when your brain feels like mush.
Also, make sure it’s realistic. Try to focus on three to five things you can actually accomplish. It’s a plan, not a wish list.
5. You’re glued to your phone
If you do random scrolling before bedtime, (I call it Doomscrolling), it can distract you, which keeps you awake, stimulates your brain and delays REM sleep. In fact, when your brain revs up, it can keep you awake for hours beyond your normal bedtime.
So do yourself a favour and set the tone for the day by using an alarm clock rather than relying on your phone to wake you up.
And try your best to make sure the time when you wake up and before you go to bed is phone-free.
If you’re enjoying this topic, you might also like to watch Dr Arun’s Youtube Video Does Sleep Effect Your Weight?
Helping You Discover, Empower & Prosper
Dr Arun Dhir | GI Surgeon, Health Reformist & Passionate Educator.

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About Dr Arun:
Besides having a busy private practice at Melbourne Gastro Surgery – Centre for Weight Loss, Dr Arun is an active member of the ANZ Association of Gastro-Oesophageal surgeons (ANZGOSA), ANZ Society of Metabolic and Obesity Surgery (OSSANZ) and Australian College of Nutrition and Environmental Medicine (ACNEM).
Dr Arun is also a senior lecturer (University of Melbourne) and yoga and meditation teacher, with a strong interest in the mind-body-gut connection. He regularly writes and speaks about gut health, gut microbiome, obesity, gastrointestinal surgery and healing. Arun’s published works include Happy Gut Healthy Weight (Balboa Press 2018), Creating a New You – Health Journal (Metagenics 2019), and Your Mess Has a Message (2021).