What is the relationship between nutrition and sleep? 

As with just about every factor of our health and diet, there is a huge connection between what we eat and how we sleep, including the time spent in different stages of sleep, duration, ability to fall asleep, and ability to wake up feeling rested and energized. 

The standard American diet of ultra-processed foods, high saturated fats, and low fiber is strongly associated with poor sleep quality and duration.⁵ But does that mean you can never have an after-dinner bowl of ice cream again if you want better sleep? Not necessarily. Let’s take a look at some of the dietary patterns and foods that can help improve your sleep.

Carbohydrates and sleep

Carbohydrates have been one of the most demonized food groups in American culture for years now (as healthy fats have become more accepted). However, our bodies need quality carbohydrate sources for sustainable energy, and as it turns out, for getting better sleep. 

Research has shown that a high quality carbohydrate meal at dinner can make falling asleep easier and reduce wake time during the night, while a low carb diet caused significant sleep disruptions and difficulty maintaining sleep. This may be due to higher tryptophan and melatonin content in some carbohydrate foods.⁶

Does this mean you should only eat carbohydrates for breakfast, lunch, and dinner? Probably not, and certainly the type of carbohydrates will affect your sleep as well. Skip the processed snacks—Whole foods like potatoes, whole grains such as quinoa and brown rice, squash, and fruit are great carb sources to include with your meals, especially with dinner, for better sleep. 

Mediterranean diet and sleep

The Mediterranean diet has also shown promise in reducing the symptoms of insomnia in women in particular. This aligns somewhat with the higher carb theory above, as the macronutrient composition of the Mediterranean diet is roughly a quarter protein, a quarter healthy fats, and half high quality carbohydrates from whole food sources (although they can vary greatly by region).⁷

The Mediterranean diet is also high in a variety of necessary micronutrients (vitamins and minerals) and phytonutrients (beneficial plant compounds like antioxidants), which we’ll cover next. 

What micronutrients affect sleep? 

A number of essential micronutrients have been found to affect sleep duration and quality. 

Deficiencies in vitamin B1, folate, phosphorus, magnesium, iron, zinc, and selenium have been associated with shorter sleep duration. Low selenium, calcium, vitamin D, vitamin C, and lycopene were also connected to poor sleep quality and maintenance. 

Increasing zinc-rich foods in particular has been shown to improve the ability to fall asleep and get better sleep.⁸

The amino acid glycine, as well as magnesium, sodium, potassium, and electrolytes in general are all well-known to lower cortisol, modulate the stress response, and improve sleep quality.⁹

What foods can help with sleep? 

Now for the fun part: let’s dig into some specific foods that can help you get a better night’s rest.  

Milk

Finally, a reason to choose dairy! While many people have trouble with digesting dairy, if you can tolerate it, milk can help you fall asleep and stay asleep due to high tryptophan, calcium, and other essential minerals. Plus, it comes pre-balanced with protein, fat, and carbohydrates. Goat’s milk or sheep’s milk may be a good option for those who have trouble with cow’s milk.⁸

Kiwi Fruit

The round, furry and deliciously sweet kiwifruit has been shown to increase total sleep time and sleep efficiency (the time you spend asleep in relation to the time you spend in bed), and decrease wake time after onset of sleep. This may be due to a number of factors with kiwis: they have a high antioxidant content, high vitamin C and E, and they are one of the few foods to contain high levels of serotonin, which has been associated with improved sleep. Researchers found that two kiwis eaten one hour before bed over four weeks produced the improved sleep results.⁸

Tart cherries/juice

Research has also found favorable associations with tart cherries and improved sleep quality. Tart Montmorency cherries have a high melatonin concentration, and researchers found an increase in melatonin levels in participants who drank tart cherry juice. This led to longer total sleep time as well as increased sleep efficiency. If you struggle with sleep but have been reluctant to use a melatonin supplement, tart cherry juice might be a good food-based option to try.¹⁰

Seafood

Oysters contain high zinc levels, which we have already connected to better sleep. Fatty fish like salmon may also have some sleep benefits due to higher vitamin D content, but this hasn’t been studied extensively.¹¹

What foods interfere with sleep? 

Of course, there are also foods that can make sleep more difficult. If you have sleep troubles, it may be beneficial to avoid these foods for a while and see whether your sleep changes. 

Caffeine

Of course, we all know that caffeine can disrupt sleep. Whether you drink coffee, soda, black or green tea, or eat chocolate, consuming these in small amounts earlier in the day may be better for your sleep quality. Some of these foods have health benefits too, such as antioxidants and essential minerals, so you don’t necessarily have to eliminate them completely. But depending on your caffeine sensitivity, it might benefit you to cut back.¹²

Processed Sugar (by itself)

Our cells run on glucose, so some sugar is absolutely necessary to maintain your metabolic health. But high-sugar, low-fiber (usually processed) foods like candy, cookies, cake, sugary cereals, etc. aren’t good for your health or your sleep quality. A study on Japanese women found that a diet high in confectionary and noodles was associated with poor sleep quality, while a diet high in fish and vegetables was associated with higher sleep quality.⁸

Tips for supporting sleep with nutrition

There are a few different strategies you can try with your diet to improve your sleep quality and hit the recommended 7-9 hours. To determine what works well for you, try out just one strategy at a time and see how your sleep is affected. 

Try a bedtime snack

Believe it or not, your body needs fuel to sleep. Although you aren’t awake and moving, your body is doing a huge amount of work repairing, and regenerating your body while you’re asleep (especially during REM sleep). And to do this, it needs fuel. So some people may benefit from a small bedtime snack an hour or so before bed.¹³ 

As some of the research has suggested, a glass of milk might be a good option for a balanced protein, fat, and carbohydrate snack, if dairy is tolerated. Kiwifruit or tart cherries may be another option to try for their high serotonin and melatonin content. Others may do better with a carbohydrate source like a small sweet potato or a slice of whole grain toast. Every dietary pattern is unique, so explore different options to see what suits you the best.^{8, 10} 

On the flip side, some research advises you to avoid eating before bed 

Research suggests some people sleep better by not consuming anything for several hours before bedtime. This might be you if you have digestive trouble or you tend to have your largest meal for dinner, so you don’t feel hungry before bed.

Eat regular meals

Skipping breakfast and eating meals irregularly were strongly associated with poor sleep quality.⁸ Make sure to eat regularly and eat balanced meals with protein, fat, and carbohydrates. Remember, some people do well with fasting, but others don’t. Establish an eating schedule and listen to your body’s cues to see if you need to make adjustments. 

Don’t fear carbohydrates

If you’re eating a very low-carb diet and not sleeping well, don’t be afraid to add in some more fruit, whole grains, potatoes, or other balanced carbohydrates. Carbohydrates are fuel for your metabolism, and not sleeping well is your body’s way of telling you that something is off. Slowly increase your carbohydrates, and see if eating more of them at dinner helps with your sleep.⁶ 

How you eat matters

This is one tip that isn’t talked about as often, and that’s to be mindful of how you eat your meals. Are you eating on the go, chewing just a few times before swallowing and reaching for the next bite? Do you feel rushed when you eat? Or can you take the time to slow down, chew each bite thoroughly, use all of your senses to experience your food, enjoying yourself in the company of family and friends during meals? 

The former puts you in sympathetic overdrive, heightening stress hormones and negatively impacting digestion while you eat, while the latter promotes the parasympathetic rest and digest state, allowing you to digest your food properly and assimilate all of the nutrients your body needs. Less stress + more nutrients = better digestion + better sleep.¹⁴

Connecting your diet to your sleep

Diet and nutrition absolutely have an effect on sleep duration and quality. If you are one of the millions of Americans that are affected by poor sleep, we hope that you give these tips a try and see how you can improve your sleep with specific diet and nutrition changes. 

For more information on circadian rhythms and how they affect sleep patterns, check out the UT Department of Nutritional Sciences’s blog on Dr. Takahashi and his research.