Understanding the Connections between Sleep and Nutrition

By: The Duke Health & Well-Being Nutrition Team

Sleep plays an important role in health and well-being throughout the lifespan. Like most aspects of health, nutrition can play an important role. Sleep and nutrition have a cyclical relationship; sleep quality can affect hunger cues and lead to increased risk for weight gain, while proper nutrition and timing of meals can improve sleep quality and enhance health. Following a few simple nutrition recommendations can improve this relationship and help produce more nights of restorative sleep.

The Importance of Sleep

Sleep is essential not only for being productive during the day, but also for supporting brain function, growth, and physical health over the lifespan. The effects of a bad night’s sleep can sometimes be felt the next day, causing lethargy, inability to focus, and excess hunger. Poor sleep over the years can also impact an individual’s risk for chronic health problems, including heart disease, kidney disease, hypertension, and diabetes. You may have been advised by your health provider to work on getting better sleep for a variety of health reasons.

Sleep & Nutrition

Nutrition has an important effect on sleep quality and the body’s natural clock, or Circadian rhythm. Eating habits can impact sleep quality primarily by influencing neurotransmitters, hormones, and digestion. Neurotransmitters and hormones help control our sleep patterns, but they also influence all of the body’s natural processes.

Digestion slows down during sleep, causing food to sit in the stomach longer than usual. Eating heavy or large meals close to bedtime can disrupt sleep by increasing acid reflux symptoms and causing indigestion. Depressants (such as alcohol) and stimulants (such as nicotine and caffeine) can also have detrimental effects on sleep quality and should be avoided close to bedtime.

Not only is it important to pay attention to what we eat before bed, but also when we eat during the day. Most evidence suggests that a consistent diet, eating the bulk of food earlier in the day, and avoiding eating late in the evening can improve sleep quality.

Sleep & Increased Weight Risk

Research suggests that shorter sleep times are correlated with increased weight gain and waist circumference for all age groups. Sleep deficiency also increases one’s risk of developing obesity. The relationship between sleep and weight remains unclear, but a few mechanisms have been proposed to explain this relationship.

Appetite Hormones

Sleep influences the appetite-regulating hormones ghrelin (the hunger hormone) and leptin (the satiety hormone). Poor quality sleep increases ghrelin and decreases leptin, which may result in increased hunger sensations with decreased satiety. When our body feels hunger, the brain signals us to grab foods that increase energy. Frequently, these foods are high in refined sugars and fat, which give a short-term energy burst. This usually results in energy spikes that cause us to feel hungry again sooner than usual and reach for more energy, which in turn leads to higher calorie intake.

Cortisol Levels

Poor quality or insufficient amounts of sleep is also correlated with elevated cortisol (the stress hormone). Elevated cortisol contributes to the deposit of excess energy as adipose in the abdomen. Increased abdominal adiposity can lead to insulin resistance, which then makes weight loss even more challenging. Taking action to improve sleep patterns may reduce cortisol levels, making it easier to lose weight if that is your goal.

Sleep Recommendations

Most adults should aim for 7-9 hours of sleep per night. This range is a recommendation; some individuals might function better when getting more than the recommended amount of sleep, while others may function normally on the lower end of this range. Sleeping less than six hours each night is not recommended for most adults.

Quality of sleep is just as important as the amount. Sleep consists of two basic phases: rapid eye movement (REM) and non-REM. Non-REM sleep is commonly known as deep sleep and is the phase where our bodies perform the most healing and rehabilitating processes. If you frequently wake up feeling unrested, you might not be getting enough non-REM sleep. A good night’s sleep usually consists of 3-5 cycles of REM and non-REM sleep per night.

Nutrition Recommendations

Eat your last meal or snack a couple of hours before bedtime.

Eating a couple of hours before bedtime will give your stomach time to digest food before going to sleep. As discussed above, sleep slows digestion, causing food to sit in the stomach longer and create more stomach acid. Though you may not be conscious of the impacts of indigestion while you are sleeping, you will likely feel the effects of a poor night’s sleep the next day.

Keep a consistent diet.

Just as sleep contributes to the body’s Circadian rhythm, so does your diet. Eating close to the same time each day and making sure to have a healthy balance of nutrients will aid in aligning your body with its natural rhythm, which might in turn improve sleep.

Eat more during the daytime and less at night.

As mentioned previously, when food is eaten too close to bedtime digestion will slow and lead to lower quality sleep. If the majority of food is consumed during the day when the body is still active, the majority of digestion can finish before sleep. Removing the need for digestion allows the body to focus on repair, restoration, and elimination of metabolic by-products during sleep.

Consume foods that improve sleep.

Some research indicates that foods high in melatonin, tryptophan, and magnesium may help improve sleep quality. Dietary sources of each are listed below.

• • Melatonin – Eggs, fish, nuts, seeds, berries, tomatoes, and peppers.
  • Tryptophan – poultry (chicken & turkey), eggs, fish, milk, tofu and soy products, chocolate, and seeds.
  • Magnesium – Fish, nuts, seeds, legumes, fortified grains, spinach, and soy product.

Moderate caffeine and alcohol consumption.

Caffeine is a stimulant. Stimulants disrupt sleep by blocking sleep-inducing hormones and increasing adrenaline production. Though consuming up to 250 mg of caffeine, or three 8-oz cups of coffee, a day is considered safe, the stimulating effects of caffeine may impact the body’s Circadian rhythm, making it harder to fall asleep, remain asleep, and enter deep sleep cycles. Caffeine can also create a harmful dependency cycle if left unregulated.

Alcohol is a depressant. As a depressant, alcohol may increase adenosine (a sleep-inducing hormone) and help you fall asleep quicker. However, it also impacts the ability to enter deep sleep and remain asleep, causing poorer quality sleep overall.

Whether you already have an established bedtime routine or are looking for new ways to improve your sleep, nutrition is an essential component to consider. Making a few small changes to your daily diet can improve sleep quality and enhance health for years to come.

For more information:

Please visit www.SleepFoundation.org

Helpful articles include:

• Why do we need sleep?
• This is your body on no sleep

These resources were developed by Erin Hancock, Intern at the Duke Diet & Fitness Center and the Duke Health & Well-Being Nutrition team:

Duke Diet & Fitness Center
Elisabetta Politi, RD, MPH, LDN, CDE – Nutrition Director
Christine B. Tenekjian, MPH, RD, LDN – Clinical Dietitian

Duke Health & Fitness Center
Kara Mitchell – Wellness Manager, Exercise Physiologist & Dietitian/Nutritionist
Samantha Mendelowitz – Dietitian/Nutritionist – Clinical Dietitian
Jenni Biggs – Dietitian/Nutritionist – Clinical Dietitian, Certified Diabetes Educator

Duke Integrative Medicine
Joanne Gardner, MS, RDN, LDN – Integrative Dietitian / Nutritionist
Jill Brown, MS, RDN, IFNCP, CLT – Integrative Dietitian / Nutritionist
Gretchen L. Hofing, MPH, RD

About Duke Health & Well-Being Nutrition & Lifestyle Services

Our individualized nutrition services are utilized to treat specific health conditions, manage weight healthfully, and to attain optimal vitality through a wholesome diet. Our nutritionists understand that getting on the right path toward your health goals is a process that requires support, adjustment, and taking small steps to make lasting and positive changes. Work with a nutritionist to discover the connection between food, movement, stress, and rest and make strategic changes to your diet that will help you achieve your goals.

Services Available
Integrative Nutrition at Integrative Medicine
Diet & Nutrition Counseling at the Diet and Fitness Center
Nutrition Consultations at the Health and Fitness Center