Angela - Wordpress FP

Do you notice yourself hungrier after a poor sleep? Your mind is not playing tricks on you, this happens and there is a strong link between your sleep and how hungry you feel.  

What is a circadian rhythm?

It is a 24-hour clock that is running in the background of your brain. It cycles between sleepiness and alertness. For most adults, the biggest dip in energy happens somewhere between 2:00 a.m. to 4:00 a.m. and mid-afternoon between 1:00 p.m. to  3:00 p.m. Have you noticed yourself needing sweets or reaching for that afternoon coffee?  

The good news is, if you are properly rested (meaning not sleep deprived) you will not feel such big dips in your energy and alertness throughout the day. The bad news is sleep deprivation will exacerbate these dips in energy, leaving you feeling worse and influencing your hunger.  

Irregular or limited sleep will disrupt your circadian rhythm and endocrine hormones. When our circadian rhythm is disrupted, it usually impacts our metabolism as well.  

There are several hormones that are affected by limited sleep that may lead to feelings of greater hunger, less satisfaction post meals, and weight gain over time. Specifically, ghrelin (our hunger hormone) increases with a lack of sleep, causing you to want to eat more. We tend to crave sweet items because our bodies primary source of fuel/energy comes from carbohydrates and sugars. In addition, leptin (our appetite suppressing hormone) decreases, so now your body is not signalling that it is full, which can lead to overeating.  

Research has found that short sleepers were more likely to consume more calories in the form of snacks than actual meals (Kant & Graubard, 2010). A 2015 review article (Dashti et al., 2015) found that short sleep duration is associated with higher total caloric intake, higher fat intake, and diets with lower protein intake. Interestingly, this review study also identified that those who slept less tended to have less consistent meals (e.g., not three times per day) and often ate high energy foods throughout the day, with an excess of calories concentrated in the evening. In addition, short sleepers reported higher intake of both caffeine and sugary foods (Kant & Graubard, 2010). It should be noted that short sleep duration was typically noted (in many research studies) as less than six hours per night.  

Sugar is our body’s primary and preferred source of energy; it makes sense that when we are tired, or our body is fatigued that we would crave/desire foods that give us a quick boost in energy. The problem is quick boosts are short lived and often lead to quick and big crashes in energy. For example, research has identified that those who sleep less are also less likely to be physically active throughout the day compared to those who had adequate sleep. This is likely attributed to a decrease in overall energy levels because of fatigue. Although not directly related to cravings, physical activity and energy levels throughout the day contribute to an overall healthy lifestyle.  

Bottom line: Less sleep = more cravings. It can lead to overeating and can influence how your hormones and metabolism are functioning. Sleeping less than six hours seems to be most problematic.  

What can you do to help?

If sleep is truly an issue, finding a way to prioritize your sleep and improve your sleep quality is crucial. Things that can help improve sleep quality include reducing screen time before bed, not eating too close to bedtime, sleeping in a dark space, and sleeping at an ideal temperature (17-19 degrees Celsius).  

To help manage cravings try:

1. Making sure you are drinking enough water throughout the day. The average person needs at least 2L. 

2. Start your day with protein and try to include some source of protein at each meal. This will help keep you fuller longer.  

3. Plan your meals and snacks. Having a plan and your fridge and/or pantry stocked to support healthy eating habits makes all the difference. 

4. Do not keep your food “triggers” in the house all the time. Save purchasing as a special treat. 

5. Do not let yourself get too hungry. It often creates cravings, lack of control, and overeating. Try to eat at regular intervals throughout the day that work for you and your body. 

6.  Aim to have healthy snacks handy and available to you. Reach for those first when a craving hits!  


Angela Wallace is a registered dietitian, family food expert, canfitpro Personal Training Specialist, and Pilates instructor. She specializes in nutrition and fitness for women and children. She specifically works with weight management, gut health, fertility, pre/postnatal nutrition, and all things family nutrition. 

Follow her on Instagram @eatright_rd