How Can Poor Sleep Increase Food Cravings and Negatively Impact Mental Health?

Sleep deprivation is all too common in today’s world, affecting about one in three US adults and contributing to numerous physical and mental health concerns such as depression, anxiety, increased weight, and obesity. However, it isn’t just adults that require quality sleep; early-life sleep loss is associated with an increased risk of obesity throughout childhood and adulthood! Adults need seven to eight hours of sleep each night in order to avoid the adverse effects of sleep deficiency, while children under five require 10 to 13 hours of sleep daily. 

So how does sleep deprivation promote food cravings and weight gain, exactly? Firstly, sleep deficiency decreases energy expenditure and increases hunger and food intake. When we’re sleep deprived and fatigued, we’re less likely to engage in physical activities such as running, walking, and playing sports — and we’re more likely to snack, eat irregular meals, and choose heavily processed foods. 

Secondly, more waking time available means more time to snack. And while eating more of the right foods is super beneficial to the mind and body, our weight, mood, and overall mental health suffers when we’re deprived of sleep and eating less-than-nutritious foods (think foods loaded with trans and saturated fats, sugars, and sodium). You can learn more about the link between nutrition and mental health here.

Lastly, the hormones ghrelin and leptin come into play. Ghrelin is a hunger hormone that stimulates appetite, while leptin is a fullness hormone that induces satiety. An imbalance of these two hunger hormones occurs when we’re not getting adequate sleep each night, elevating ghrelin (hunger) levels and lowering leptin levels (feelings of satiety). These imbalances can lead to food cravings, overeating, and in some cases, obesity. 

Let’s take a closer look at how poor sleep quality affects hormones, increases cravings, promotes weight gain, and harms mental health — so you, my friend — can take steps to achieve a better night’s rest.

Why Does Lack of Sleep Increase Appetite?

Now that we’ve discussed how sleep deprivation increases cravings and promotes weight gain, let’s take a closer look at ghrelin, leptin, and a few of the other “hunger hormones” that come into play here. 

Ghrelin & Leptin

As I mentioned earlier, ghrelin and leptin imbalances commonly occur due to sleep deficiency. This is because leptin levels (feelings of fullness) are meant to rise when we sleep. When we aren’t getting at least seven hours of sleep each night, our leptin levels decrease, our appetite increases, and excessive eating occurs when we’re awake.  

Additionally, any type of sleep disruption (whether sleep deprivation or poor quality sleep due to sleep disorders and other factors) can cause our ghrelin levels (feelings of hunger) to increase. When leptin levels decrease and ghrelin levels increase, we tend to feel hungrier than we really are — resulting in overeating and possibly weight gain and obesity. 

That being said, eating lots of protein-rich meals and high-fiber foods like fruits and veggies, beans and legumes, and whole grains decreases ghrelin production and regulates appetite. One review article published in the European Society of Endocrinology reported that dietary pulses (such as fiber-rich beans, legumes, and peas) increased feelings of satiety by 31 percent. More reasons to consume a whole-food diet! 

Balancing leptin and ghrelin levels through quality sleep, regular exercise, and good nutrition can all help to regulate appetite, prevent weight gain, and support physical and mental health. My Free Food + Mood Guide is centered around foods that nourish the body and mind AND keep you full; claim your copy to jumpstart your health and wellness journey! 

Serotonin, Dopamine, Melatonin, & Cortisol

In addition to the hormones ghrelin and leptin, serotonin, dopamine, melatonin, and cortisol are three other hormones responsible for regulating appetite and cravings. These hormones also have a major effect on our mental health, sleep quality, and daily functioning. 

Serotonin, for instance, is a neurotransmitter that regulates everything from our memory and mood to our sleep, hunger, and body temperature. It works alongside dopamine, another neurotransmitter, to help us fall asleep, achieve a good night’s rest, and wake up feeling refreshed. Both hormones affect our appetite as well; serotonin suppresses feelings of hunger while dopamine stimulates appetite. 

What’s more, serotonin is needed to produce melatonin, a hormone that’s commonly known as the “sleep hormone” or “sleepy hormone”. It plays a role in the management of our circadian rhythm and sleep-wake cycle; our bodies produce melatonin when we’re exposed to darkness, helping us fall asleep and sleep better throughout the night. 

When we’re exposed to morning light, melatonin levels decrease and cortisol levels rise to help us wake up. Known as “the alert hormone”, cortisol is basically the opposite of melatonin. Cortisol levels should be highest when melatonin levels are low and lowest when melatonin levels are high. 

Melatonin, Cortisol, & Cravings

Like serotonin and dopamine, melatonin and cortisol also affect our eating habits and appetite. When cortisol levels are higher than normal — for instance, during times of stress — ghrelin levels increase (stimulating our appetite) and the region of the brain known as the hypothalamus becomes less sensitive to leptin (feelings of fullness). This tricks us into thinking we’re hungrier than we really are, which can lead to overeating (and in many cases, eating too many of the wrong foods). 

Furthermore, research in mice shows that food cravings and increased appetite can occur when melatonin levels are low. Melatonin levels naturally decline with age (especially after age 40), but other factors that decrease melatonin production include obesity, night work, and disruptions in light-dark cycles (for example, excess light exposure in the evening). Practicing good sleep hygiene and incorporating other healthy habits into each day increases melatonin production in the evening and improves sleep quality for a better night’s rest: 

• Wake up and go to bed at the same time each day.
• Follow a bedtime routine that relaxes you (e.g. take a warm bath, meditate, practice deep breathing, or read a book*). 
• Avoid drinking caffeine in the evening and late afternoon.
• Avoid drinking alcohol before sleep (at least 4 hours to reduce the chances of alcohol disrupting your sleep). 
• Create a calm, cool, and comfortable sleep environment. 
• Take steps to reduce stress before going to bed: try journaling, yoga, or using a weighted blanket. 
• Practice intuitive eating throughout the day (benefits of mindful eating include improved sleep, digestion, and reduced stress).  
• Eat balanced meals with a focus on fiber-rich foods, whole grains, healthy proteins, and gut-friendly probiotics and prebiotics. 
• Try Cognitive Behavioral Therapy for Insomnia (CBI-I) if you struggle to fall asleep or stay asleep. 
• Stimulate your vagus nerve daily to support quality sleep and digestion (two examples of vagus nerve stimulation include humming and gargling).

*Print books and magazines are best in the evening since electronic reading devices emit blue light, interfering with sleep. If you do use your phone, laptop, or eReader before bed, be sure to wear a pair of blue-blocking glasses. You can also use night mode or night light mode on your devices to reduce the amount of blue light they emit. I even go so far as to dim the lights in my house and avoid watching tv before bed as it gets closer to sunset.

Hunger Hormones, Body Weight, & Depression

We now know that quality sleep, regular exercise, good nutrition, and self-care can all help to balance hunger hormones, decrease cravings, and prevent excessive weight gain. Balancing these hormones also prevent mental health concerns such as depression. One meta-analysis found that over time, individuals with obesity were 55 percent more likely to develop depression. 

Furthermore, decreased self-esteem and increased body dissatisfaction are common among individuals living with obesity as well as people who are struggling with emotional or disordered eating. If you’re struggling with any of these issues, you’re not alone! Many of my clients first come to me with these same concerns. This is why my approach to wellness incorporates food and nutrition as well as sleep, stress, movement, mind-body modalities, and genetic testing. So many factors affect our physical and mental well-being!

If you’re interested in learning how to combat emotional eating or are on your journey of practicing self-compassion, I would highly recommend joining either private or collective coaching to watch my classes and get support on these topics. 

Now on the topic of genetics…

Genetic Variations & Sleep Deprivation

Multiple factors contribute to sleep loss or poor quality sleep, from genetic variations in the CLOCK gene to lifestyle choices, stress, medications, and new parenthood. But because genetic testing is a huge part of what I do at The Fulfilled Fork, we’ll dive deeper into genes in this next section. 

How Does the CLOCK Gene Affect Sleep, Mental Health, & Weight?

Formally known as the Circadian Locomotor Output Cycles Kaput (CLOCK) gene, genetic variations in this gene are associated with various biological and behavioral processes such as 

metabolism, mental health, and sleep. This gene also plays a role in our diurnal preference (a preference for the morning or evening). 

CLOCK rs1801260 (A/G), for example, is one single nucleotide polymorphism (SNP aka a genetic variation) in the CLOCK gene that’s been associated with sleep, obesity, metabolic syndromes, and weight loss success. In a study published in the International Journal of Obesity, researchers found that weight loss was much more difficult among G allele carriers (minor allele carriers) and that these individuals had a greater degree of obesity than those without the genetic variant. Carriers were also more likely to be short-term sleepers, sleeping less than six hours daily. 

Moreover, a study published in Progress in Molecular Biology and Translational Science found that carriers of the G allele in the CLOCK rs1801260 (A/G) SNP had a preference for evenings, increased daytime sleepiness, and shorter sleep duration. Researchers also found a link between the SNP and metabolic traits, nonalcoholic fatty liver disease, and hypertension — as well as sleep disturbances among those with mental health conditions such as bipolar disorder, major depression, and attention deficit hyperactivity disorder (ADHD). 

A later research article further explored the link between the CLOCK gene, sleep, and appetite. Researchers found that carriers of the minor allele (C) in the CLOCK 3111 T/C SNP were much more likely to have higher fasting ghrelin levels than non-carriers with the TT allele. Plasma ghrelin levels were higher among carriers 38 years of age and older, and these individuals were more likely to overeat later in the morning — especially on weekends. Shorter sleep duration, a preference for evenings, and difficulty losing weight were also common among carriers. 

Other Genetic Variations Associated with Sleep

In addition to these variations in the CLOCK gene, several other genetic variants are associated with sleep. For example, in the aforementioned study published in Progress in Molecular Biology and Translational Science, variants in the PER1 gene were associated with extreme preferences for mornings, and mutations in the NPAS2 gene were associated with daily timing and sleepiness, depression, and chronic fatigue syndrome. 

Some of the other genetic mutations associated with sleep include the:

• PER2 and PER3 genes.
• CK1δ gene.
• DEC2 gene.
• Timeless (tim) gene.

Furthermore, genetics play a role in the development of sleep disorders as well. We won’t discuss these genes in this blog, but I encourage you to check out this study if you’re as interested in the topic as I am!

The Bottom Line: Genetic Testing Matters

Genetic testing and coaching can tell you a great deal about your body’s unique needs, especially when it comes to sleep, diet, mood, and metabolism! To learn more about how your genes, diet, lifestyle, hormones, and other factors could be contributing to mental health issues, sleep deprivation or deficiency, or food cravings, apply for private or collective coaching today.

Ready to nourish your body, mind, and spirit and start leading your most fulfilling life? Begin your holistic mental wellness journey by applying for collective or private coaching or reading the other blogs on my website!

References:

• https://www.nhlbi.nih.gov/health/sleep-deprivation 
• https://www.nhlbi.nih.gov/health/sleep-deprivation/how-much-sleep 
• https://www.hsph.harvard.edu/obesity-prevention-source/obesity-causes/sleep-and-obesity/ 
• https://www.yalemedicine.org/news/sleep-diabetes-and-obesity 
• https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6179508/ 
• https://eje.bioscientifica.com/view/journals/eje/161/1/65.xml
• https://onlinelibrary.wiley.com/doi/10.1002/oby.20782 
• https://my.clevelandclinic.org/health/articles/22572-serotonin 
• https://my.clevelandclinic.org/health/articles/23411-melatonin 
• https://kids.frontiersin.org/articles/10.3389/frym.2019.00095 
• https://revistapesquisa.fapesp.br/en/a-connection-between-sleep-and-hunger/ 
• https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3402070/ 
• https://jamanetwork.com/journals/jamapsychiatry/fullarticle/210608 
• https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4169291/ 
• https://pubmed.ncbi.nlm.nih.gov/20065968/ 
• https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0017435 
• https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3734884/