We don’t need scientific research to realize the benefits of a good night’s sleep. For starters, we feel better when we’re well-rested. We are also less likely to suffer from chronic health conditions such as high blood pressure, heart disease, and type 2 diabetes. Of course, a healthy diet is critical for optimal health, as well. But few people realize the role good nutrition plays on sleep — and vice versa.
Sleep problems are often chalked up to stress, pain, medications, or schedule changes. But one trigger that’s often overlooked is our nutrition. Large epidemiological studies through the years have found that people with chronic sleep problems tend to have poorer diets, consume less protein, fewer fruits and vegetables, and more sugary or processed foods. Poor sleep is also linked to weight gain. Conversely, being over or underweight can adversely impact sleep.
So, do our eating habits affect sleep? Or does the quality of our sleep impact nutrition? Or both? We asked experts to weigh in. The good news is that by making some small lifestyle changes, you can improve both your sleep and your diet.
How Does Nutrition Affect Sleep?
Eating a good, balanced diet ensures your body gets the nutrition it needs to function during the day and keep you in optimal health, which protects you against chronic diseases. Nutrients are substances in food such as carbohydrates, fats, proteins, vitamins, minerals, and water. It turns out, the amount and quality of those nutrients can affect sleep.
For example, studies have found that people with high-carbohydrate diets drift off to sleep faster at night compared to those who consume high-fat or high-protein diets. But, according to a study published in the Journal of Clinical Sleep Medicine, the quality of those carbs count. It found that when people eat more sugar and simple carbs (white bread, pastries, pasta), they wake up more frequently during the night.
Hormones may be to blame. When you eat carbs, glucose from these foods travels into your bloodstream and triggers your pancreas to release insulin — one of the most well-known hormones that affect diet.
“The body makes hormones that regulate sleep/wake cycles, and the food we eat are the building blocks. Therefore, what we eat or don’t eat can influence these hormones that can have an impact on sleep,” says Holly Klamer, a registered dietitian with My Crohns and Colitis Team. “According to a 2020 review, nutrition can profoundly affect the hormones and inflammation status which directly or indirectly contribute to insomnia.”
How Does Sleep Affect Nutrition?
The quality of the nutrients we consume during the day and, especially before bedtime, can impact sleep. But what about the reverse? Can the quality of our sleep impact our dietary choices?
“Lack of sleep is not uncommon. I have come across so many people who have been going out of their way to eat right and stay healthy but the weight simply does not seem to budge on the scale. A good night’s sleep of 7-8 hours is the only lifestyle change they needed,” says nutritionist Vasundhara Agrawal.
That’s because sleep deprivation leads to an imbalance in the hormones ghrelin and leptin which control appetite and hunger. “Leptin tells our body when to stop eating and lack of sleep reduces leptin levels. Ghrelin levels on the other hand are raised which trigger feelings of hunger,” she says. “This is probably why you are reaching out for a packet of chips or cookies when you’re hungry late at night.”
That is likely why there is an association between inadequate sleep and weight gain. “Not getting enough sleep and feeling tired throughout the day can lead to overeating,” Klamer says, citing a 2013 study that concluded that eating more when not getting enough sleep is a physiological adaptation to provide the energy needed to sustain additional wakefulness. “Not getting enough sleep, along with a late bedtime, can also lead to eating more at night which can further promote weight gain,” she says.
To add injury to insult, Agrawal adds, “Lack of sleep also puts your body under stress and the body releases the stress hormone cortisol which decreases your blood sugar levels resulting in poor food choices and cravings for foods high on fat or sugar.”
How to Improve Sleep and Nutrition
The good news is that the reciprocal relationship between nutrition and sleep means that you can also improve your sleep by improving your diet. And getting plenty of restful sleep means you are less likely to reach for a late-night snack of Twinkies. How do you go about making these changes? Our experts offered these suggestions:
- “Eating balanced and consistent meals with a balanced distribution of carbohydrates, protein, and fat, can help moderate blood sugar and energy levels, which can help moderate blood sugar and energy levels, which can help with overall energy levels and sleep,” says Sarah Schlichter, a registered dietitian with Bucket List Tummy.
- Avoiding high fat and high sugar snacks before bed also helps balance insulin levels to help you sleep better.
- Drink plenty of water during the day to help stay hydrated and flush out your system, But avoid guzzling too much water before bedtime. Otherwise, you’ll frequently be waking at night to visit the bathroom, Schlichter cautions.
- Wait at least two hours after your last meal of the day before going to bed, says Alexandra Soare, a registered dietitian at Food-on-Mars.com. “In case you’re still hungry, make sure to pick the right bedtime snack,” she says, such as foods naturally high in the sleep hormone melatonin, like cherries, kiwis, and bananas.
- Steer clear of stimulants too close to bedtimes, such as caffeine and nicotine. Remember that caffeine is often present in sodas, chocolate, and hot teas.
- Alcohol is a depressant which means a nightcap can help you fall asleep faster. But be sure to limit your intake. Too many drinks before bedtime can interfere with restorative REM sleep.
- Improve your sleep hygiene. For example, create a relaxing nighttime routine by incorporating time to practice stress-relieving activities such as yoga or meditation before bedtime, Agrawal suggests.
- Improve your sleep environment by investing in a comfortable and supportive mattress, using light-blocking blinds to keep out unwanted light, setting the thermostat a few degrees cooler than you keep it during the day, and being sure you’re wearing comfortable pajamas.
- Monitor your sleep with a sleep tracker or mobile app. This can help you keep track of the hours of sleep and whether adjustments need to be made with your bedtime or wake time.
- Consult with a professional. If you have certain dietary restrictions or need assistance structuring a healthy diet, consult with a dietitian or nutritionist. If you are concerned you may be suffering from a sleep disorder, talk with your doctor or a sleep specialist.
Scientific research shows that the relationship between sleep and nutrition is closely intertwined. Not only do poor food choices interfere with restorative sleep, but we are also more apt to make poor food choices when we are deprived of restful sleep. The good news is that by making some small lifestyle changes, we can improve the quality of our sleep and our diets — which translates to better overall health.
If you struggle to transition to a healthier diet or have health issues that limit the types of foods you can eat, consider talking with a dietitian or nutritionist to identify a better nutritional diet that helps promote restful sleep.