In modern society, sleep deprivation has become commonplace. We all know about the age old goal of 7-8 hours of sleep, but in reality, so few of us get consistent restful sleep. For most, sleep is the first thing to be put on the backburner. However, there is more and more research coming out every day about the importance of sleep to promote health and wellness. Research suggests that consistent insufficient sleep not only increases inflammation, cardiovascular disease and overall mortality but also decreases cognition and immune function. What might be the most surprising, however, is the effect of insufficient sleep on hunger, satiety and metabolism.

Physiology of Sleep

The majority of adults spend at least ⅔ of each day in the awake phase, however as the day comes to a close people snuggle up in their beds and head off to sleep. The purpose of sleep is for restoration, energy conservation and memory consolidation. 

Sleep can be broken down into two phases. Most well known is REM sleep, which stands for rapid eye movement. REM sleep has been studied quite extensively and is most often associated with vivid dreaming. The majority of time slept, however, is spent in what is known as non-REM sleep. This consists of both light and deep sleep.  Both REM and non-REM play an important role in sleep quality. Abnormalities in either of these phases can result in various sleep disorders.

For optimal health, we require sufficient sleep quality and quantity. If either of these is not met, then health begins to suffer. What’s difficult is that the sufficient duration of sleep varies based on age, stress, and other personal differences. For more information on current sleep guidelines, you can visit the National Sleep Foundation.

Physiology of Hunger

Before we dive into the relationship between sleep and hunger, let’s first learn the basics of hunger and satiety. Appetite is controlled by a number of hormones, most notably leptin and ghrelin. 

Ghrelin is a hormone produced by the stomach in times of fasting. Therefore in between meals ghrelin steadily increases to stimulate hunger. Furthermore, research has shown that ghrelin not only affects short term hunger but also long term weight regulation.

Leptin is a hormone that is produced by fat cells and circulates throughout the blood. Opposite to ghrelin, leptin is associated with appetite suppression. It is currently understood increased leptin results in decreased food intake. 

The Relationship Between Hunger and Sleep

As mentioned earlier, insufficient sleep is associated with a host of negative health effects, one being hunger dysregulation.  This relationship between sleep, hunger and metabolism has been researched extensively. Studies have shown that insufficient sleep has a direct effect on regions of the brain (prefrontal cortex, inula and amygdala) that determine food desire, specifically for high-calorie foods. These alterations in neural pathways thus have an effect on the amount and types of foods eaten after a night of poor sleep.

In addition to neural pathways, sleep also plays a role in the regulation of leptin and ghrelin. A number of studies have found that decreased sleep duration and quality are associated with increased ghrelin levels the following day, resulting in increased hunger. In addition, leptin, the appetite suppression hormone, was decreased. Ultimately, this study and others have found that as the amount of sleep increases, overall hunger decreases. In addition to disrupting ghrelin and leptin levels, other studies have found that insufficient sleep increases the potential for insulin resistance, which may potentially develop into diabetes.

Sleep Promoting Habits

Clearly sleep is important, but many people have difficulties with falling and staying asleep. Before jumping to a sleep inducing herb, supplement, or medication, it is important to first look at supporting a healthy sleep routine. 

Create Your Sleep Sanctuary

For restful sleep, it is important to first address your bedroom environment. The most important aspect is darkness. As mammals, our sleep-wake response is tied to darkness and light. For this reason, any lights can interfere with sleep quality. This includes everything from night lights to outdoor street lights and electronics.  Covering any glowing lights and investing in blackout curtains are easy ways to minimize light exposure. In addition to lights, temperature can also affect the quality of sleep. Current recommendations suggest that bedroom temperatures be between 60-67 F for optimal sleep.

Support Your Circadian Rhythm

Circadian rhythm is our natural sleep-wake cycle, mediated by hormones such as cortisol and melatonin. In our current society, it is very common for people to be “night owls”, but this is likely some sort of circadian rhythm dysregulation, such as delayed phase sleep disorder. This means that our hormonal sleep-wake cycle has shifted and is now a few hours later. This can easily be shifted back. Studies have shown that the use of morning bright light exposure and afternoon melatonin supplementation successfully shifts circadian rhythm to an earlier time. Current recommendations suggest 30 minutes of bright light therapy within 1 hour of waking. This may be done either with sunlight or a full spectrum lightbox.

Incorporate a Relaxation Routine

Our bodies love routines. For this reason, it is important to create a relaxation routine that can subconsciously remind ourselves that it is time for bed. This can be anything from a hot bath to a good book or calming tea. Providing a simple reminder each night that it is time to wind down can be especially helpful. 

References

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3. How Much Sleep Do We Really Need? - National Sleep Foundation. https://www.sleepfoundation.org/articles/how-much-sleep-do-we-really-need.

4. Liddle R. Ghrelin. UptoDate. Last Updated April 2019. Accessed October 10, 2019. https://www-uptodate-com/contents/ghrelin.

5. Mantzoros C. Physiology of Leptin. UptoDate. Last Updated April 2019. Accessed October 10, 2019. https://www-uptodate-com/contents/physiology-of-leptin.

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8. Broussard JL, Kilkus JM, Delebecque F, et al. Elevated ghrelin predicts food intake during experimental sleep restriction. Obesity (Silver Spring). 2016;24(1):132–138. doi:10.1002/oby.21321

9. Chattu VK, Chattu SK, Burman D, Spence DW, Pandi-Perumal SR. The Interlinked Rising Epidemic of Insufficient Sleep and Diabetes Mellitus. Healthcare (Basel). 2019;7(1):37. Published 2019 Mar 5. doi:10.3390/healthcare7010037

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About the Author

Dr. Hannah is a naturopathic doctor providing whole body adjunctive healthcare to patients in Maine and Massachusetts. She believes every patient has their own unique health journey, which influences her personalized treatment approach. She has a passion for helping women, mothers and families heal and thrive, all while uncovering the root cause of whatever ails them. Her goal is to empower and guide her patients on the path towards healing the mind, body and soul through natural methods of healing. Dr. Hannah sees patients locally in Portland, Maine. Through telehealth, she is happy to serve the people of Lewiston, Ellsworth, Belfast, Bangor, and all the towns in between! She now sees Massachusetts patients through telehealth as well!

Disclaimer

The information provided on or through this website is for educational and informational purposes only. This information is not a substitution for proper and personalized medical diagnosis or treatment. Always seek the advice of your physician or trusted healthcare provider before making an adjustments or changes to your healthcare regimen. Natural medicine is not inherently harmless, and therefore it is important to speak with your healthcare providers for personalized medical advice.