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It has been estimated that between 14% and 40% of people do not get high-quality sleep, and the number of hours that people sleep each night has decreased due to our busy, modern lifestyles. Impaired sleep can negatively impact cognitive performance, metabolism, cardiovascular health, mood, and more.

Sleep deprivation can negatively affect our food choices, contribute to low-grade inflammation, and may even hinder weight loss efforts. Our dietary habits can either positively or negatively impact sleep factors such as quality, efficiency, and the time it takes to fall asleep (sleep latency). Perhaps unsurprisingly, an anti-inflammatory diet full of colorful plant foods can improve our sleep.

The Effects of Poor Sleep

While improvements in the diet can positively impact sleep, it is important to consider how sleep quality influences our metabolism, hunger hormones, and dietary decisions. Sleep deprivation seems to either cause an under- or overconsumption of food. When teenagers slept for 6.5 hours per night compared to their usual 10 hours, they consumed 11% more calories and 52% more desserts. Adults with normal sleeping patterns who committed to a period of 4 hours of sleep per night also consumed significantly more calories, along with a greater intake of saturated fat. They experienced less slow wave sleep (a deep phase of non-rapid eye movement sleep). An increased intake of saturated fat and sugar, along with less fiber, were associated with more sleep disturbances and lighter sleep. Increased fiber intake resulted in greater slow wave sleep.

On the other hand, a study of Indian adults found that those with insomnia consumed significantly fewer nutrients compared to those who reported normal sleep patterns. Intake of vitamins such as folic acid, B12, and thiamine as well as overall caloric intake from carbohydrates, fats, and protein were significantly different between the two groups.

A study of overweight adults showed that getting 5.5 hours of sleep compared to 8.5 hours decreased the amount of fat loss by 55% during a weight loss program. Fat-free body mass loss increased by 60% due to this sleep deprivation. Study participants experienced increased hunger, and their bodies adapted to caloric restriction. This means that decreasing calories was less impactful for weight loss. When participants were able to get in the full 8.5 hours of sleep, they lost more weight from body fat.

Finally, a small, inpatient study found that overnight concentrations of ghrelin and leptin were significantly affected by meal timing throughout the day, as well as sleep timing. Ghrelin is a hormone that signals appetite, while leptin signals satiety. Earlier sleep and meal times resulted in lower levels of overnight ghrelin, and earlier meal times led to higher overnight leptin. Based on this study, eating meals earlier in the day and committing to an earlier bedtime can exert positive effects on hunger hormones.

Nutrient Intake

Macronutrient and micronutrient intake are both important to consider for sleep optimization. For example, zinc, iron, and magnesium have been studied for their positive associations with total sleep duration. A systematic review found that people who reported good sleep consumed more protein compared to those with poor sleep. This may be due to the presence of tryptophan, an amino acid that serves as a precursor for serotonin and melatonin. The review also found that carbohydrates are supportive of sleep by positively influencing rapid eye movement (REM) sleep. A separate study looking at carbohydrate quantity found that a high carbohydrate intake was associated with longer REM sleep, whereas a low intake of carbohydrates decreased the duration of REM sleep. In a third study, men with normal sleep habits consumed a drink containing high-glycemic carbohydrate, tart cherry juice, valerian, and several other components thought to help with sleep. The drink with optimal levels of these ingredients helped participants fall asleep faster. Researchers in these studies suggest that carbohydrates elicit a positive effect on sleep because the actions of insulin help to increase the uptake of tryptophan in the brain.

The 2007-2008 National Health and Nutrition Examination Survey (NHANES) found that a lower intake of selenium, calcium, and monounsaturated fatty acids and an increased intake of saturated fat was negatively associated with sleep latency. Less potassium in the diet was associated with sleepiness, and less calcium and vitamin C along with increased dietary cholesterol were associated with non-restorative sleep. Difficulty staying asleep during the night was associated with lower food variety, while the greatest dietary variety was associated with normal sleep duration. Short sleep (5 or 6 hours) was associated with decreased intake of fiber and a greater intake of saturated fat and cholesterol. Less than 5 hours of sleep was associated with decreased intake of lycopene, thiamin, and folate, as well as minerals such as magnesium, iron, zinc, and selenium. Sleep deprivation was also associated with lower levels of leptin and higher levels of ghrelin.

Adults in Germany and the Netherlands were given online questionnaires to assess the relationships between different modifiable health behaviors. Physical activity and fruit and vegetable consumption (5 servings per day) were positively associated with sleep quality and an increased quality of life. Middle-aged adults had the lowest sleep quality and were less likely to be engaged in healthy behaviors such as exercise or healthy eating.

In a separate study, men with chronic insomnia committed to a six-month dietary protocol that involved a decrease in overall calories and a focus on improved nutrient consumption. Participants increased their consumption of fiber, magnesium, potassium, and vitamins A, D, C, and E through the inclusion of vegetables, fruits, beans, and nuts. The intervention group experienced significant decreases in body weight and fat mass and increases in total sleep time, sleep efficiency, and less time spent awake throughout the night.

Anti-Inflammatory Foods

Inflammatory cytokines such as interleukin-6 (IL-6) and tumor necrosis factor alpha (TNF-α) are involved in the sleep cycle, and their production can be increased with sleep deprivation. A processed diet can serve to perpetuate inflammation, whereas an anti-inflammatory diet can help to dampen inflammation’s harmful effects on the body.

Inflammatory cytokines may continue to be elevated in breast cancer survivors, and this population often experiences fatigue and poor sleep as a result. A 3-month dietary protocol with a focus on vegetables, whole grains, fruits, and omega-3 fatty acids led to improvements in fatigue. Participants aimed to consume five servings of colorful vegetables per day as well as two servings of fruit. At least one serving of fruit was rich in vitamin C, which is a powerful antioxidant. Anti-inflammatory omega-3 fatty acids came in the form of nuts, seeds, and fish. Serum levels of phytochemicals such as carotenoids, lycopene, lutein, and zeaxanthin significantly increased, and sleep quality improved by almost 50% compared to the control group.

A study of women with fibromyalgia found that the Mediterranean diet combined with tryptophan and magnesium supplementation led to lower anxiety and a significant increase in sleep duration. The Mediterranean diet is rich in fruits, vegetables, olive oil, and nuts and seeds. Participants specifically incorporated walnuts into their diet as this food is rich in tryptophan and magnesium.

The traditional Japanese diet, Washoku, has also been studied for its effects on sleep. This diet is rich in rice, vegetables, and fish. Participants in a study comparing rice consumption to other grains found that participants who consumed rice consistently over a 2-month period experienced significantly improved sleep quality, as well as reduced oxidative stress levels. Some participants in the rice group also experienced decreased uric acid levels, which is a marker associated with oxidative stress. Another study of the traditional Japanese diet found that rice, miso soup, natto, and green tea were associated with improved sleep quality. Miso, natto, and green tea are rich in flavonoids, which exert antioxidant effects.

Older adults with insomnia drank tart cherry juice for two weeks and experienced an increase in sleep efficiency and overall sleep duration possibly due to an increase in tryptophan. Inflammation stimulates the enzymatic process of tryptophan degradation, which may partially explain why inflammation can contribute to poor sleep. Tart cherry juice was found to inhibit this enzymatic process meaning more tryptophan was available to be converted to serotonin and melatonin.

People who consumed two kiwis every night for four weeks experienced a 35.4% decrease in sleep latency, 13.4% increase in total time asleep, and 5.41% improvement in overall sleep efficiency. This is thought to be due to the levels of vitamins C, E, and folate as well as carotenoids in kiwis.

Ellagic acid, a powerful antioxidant found in foods such as nuts and pomegranate, was found to improve sleep markers such as efficiency, duration, and the decreased use of sleep medications in a study of people with irritable bowel syndrome (IBS). It also decreased some symptoms of IBS such as abdominal pain.

A separate study using sesame lignans along with vitamin E found that daytime fatigue and sleep significantly improved, perhaps due to the antioxidant effects. Participants indicated significant improvements in falling asleep and waking feeling rested.

Finally, maintaining a healthy weight through diet and lifestyle can help to support quality sleep through the attenuation of inflammation. A study using a 6-month weight loss protocol found that participants with chronic insomnia experienced significant improvements in sleep efficiency, latency, and duration. The inflammatory cytokines TNF-α and IL-6 significantly decreased.

Closing Thoughts

• Sleep deprivation can impact food intake by influencing hunger hormones. This may explain why sweet treats and high-fat foods are more tempting after a poor night of sleep. If you spend the night tossing and turning, proactively set yourself up for success the next day by planning meals that are full of colorful fruits and vegetables.
• Macronutrient intake may impact sleep quality. Consuming carbohydrates later in the day (either for dinner or as a small bedtime snack) may help support sleep due to their effects on tryptophan uptake.
• A consistent dietary pattern full of colorful plant foods can help decrease inflammation and improve sleep. The next time you go to the grocery store, pick up a few fruits or vegetables that you have never tried before! Increasing the variety of plant foods in your diet supports improved nutrient intake and makes healthy eating fun!
• There are actionable steps you can take in addition to dietary changes to improve your sleep hygiene. A study of bedtime phone use demonstrated that people fell asleep faster and had significantly improved sleep quality as well as better working memory the next day when they avoided using their phone 30 minutes before bed.
• Consistent exercise is a modifiable lifestyle factor in addition to diet that can decrease inflammation. A study of older adults showed that aerobic exercise significantly increased sleep efficiency and duration while significantly decreasing TNF-α and IL-6.

If you plan to incorporate more colorful, plant-based, and/or whole foods into your daily eating; have food allergies or questions about which foods can best support your health and sleep; or have questions or concerns about your sleep habits, talk to your doctor, nutritionist, dietician, or another member of your healthcare team for personal options based on your individual circumstances. There are certain medications that may interact with plant-based foods.