Getting enough sleep
In order to wake up refreshed and ready to conquer the day, it is important to get a good night’s rest. It is recommended by the American Academy of Sleep Medicine to get 7-9 hours per night. Less than 7 hours of sleep is considered short sleep duration, which can throw us off in many ways. Lack of sleep has been associated with poor performance in normal daily activities, reduced functional capacity, impaired glucose tolerance, altered hormone levels and increased inflammation which is related to many health conditions. Not getting enough sleep can impair your brain as much as drinking too much alcohol.
While the percentage of adults getting more than 8 hours of sleep was 38% in 2001, this number dropped to 21% in 2013. The average duration of sleep for Americans is 6 hours and 31 minutes (see table 1.), but this number is declining as well. Social pressures such as work-related stress and overcommitment may lead to intentional sleep reductions. While ultimately the solution is more sleep, diet is a powerful tool to improve the sleep we do get.
During sleep our heart rate, blood pressure, respiration, oxygen in our blood, and body temperature all decrease. These changes help the body to reduce its energy expenditure so it can enter a relaxed state in order to initiate and sustain sleep. Sleep is important for circulating hormones, repairing muscles and tissues, and preparing the body for a new day.
The signs of sleep deprivation, fatigue, and even hunger can seem similar enough to be mistaken for each other. When we have not had enough sleep, our ability to detect signs of hunger and fullness is compromised. This is due to changes in our hormones called leptin and ghrelin which tell your brain when you are hungry or full. Leptin regulates our appetite and fullness by telling the body when it is full. Research has shown that lack of sleep can cause the body to have a decrease in leptin levels making you feel more hungry the next day. On the other hand, ghrelin controls our hunger cues. Lack of sleep has been associated with an increase in this hormone, leading the body to feel hungrier.
In order to set ourselves up for sleep success here are a few tips:
Hydration is vital for proper function as our body is made up of 60% water. We lose fluids while we breathe at night, which is why we are typically thirsty when we wake up. Our bodies need about 8 cups of water per day, but registered dietitians recommend spreading fluid intake throughout the day to avoid having to get up to use the bathroom in the middle of the night. Coffee, alcohol, and caffeinated teas, are diuretics which make us urinate more frequently, and if consumed too close to bedtime can cause us to wake up with a full bladder as well. Being dehydrated can prevent the body from going into that relaxed state needed for sleep. Dehydration dries out the mouth and nasal passages, which can cause morning hoarseness, dry throat, and the need to wake up in the middle of the night and chug a glass of water. These can all cause sleep disturbances. If drinking water throughout the day is not something you typically remember, try getting a reusable water bottle to track intake.
Be Cautious when Consuming Alcohol and Caffeine
Alcohol and caffeine are diuretics, which means they actively remove water from your body. Caffeine and alcohol also disrupt sleep because they are central nervous system stimulants and depressants. Alcohol, a depressant, slows your nervous system down and has been shown to cause less restful sleep by preventing the body from fully experiencing REM sleep. REM sleep is the rapid eye movement that occurs during deep sleep when dreams occur.
On the other hand, caffeine is a stimulant, which increases the amount of activity in the nervous system, and can make it harder to fall asleep. While we typically associate caffeine with coffee, it is also found in some teas, soda, chocolate, and energy drinks. The effects of caffeine typically last from 4-6 hours. The more caffeine is consumed, the less restful sleep will be. Less restful sleep will make a person more tired when they wake up, which may cause them to want more caffeine. To avoid this cycle, registered dietitians recommend not consuming caffeine 6 hours before sleeping.
Ditch the Starchy Sugary Snacks
Our bodies run on energy, which we get by breaking down carbohydrates from food into glucose. It is important to have a steady supply of glucose in our blood to maintain energy levels throughout the day. Sleep loss has a negative effect on the body’s ability to use glucose for energy. One study showed that over one week of severe sleep deprivation (of about 4 hours per night) in a healthy, lean, fit individual, they fell into a prediabetic state based on the status of their blood glucose. We want to avoid blood sugar spiking up and down like a roller coaster, because that can make us feel fatigued, irritable, and dizzy. Rather, we want it to remain consistent throughout the day. Food plays an important role in blood sugar level regulation. If it grows difficult to manage, make sure you reach out to a registered dietitian to help with meal plans and other strategies to manage blood sugar levels and ensure better sleep.
Having low blood sugar puts the body into fight or flight mode. Under these circumstances, the body releases stress hormones called cortisol and insulin. These hormones contribute to cravings for quick and fast energy which will quickly raise the blood sugar back to normal levels. Foods we crave are typically starchy and high in sugar such as candy or potato chips. These foods will not sustain us for long though, so we may end up eating a few too many servings, which can bring blood sugar much higher than the body intended. This can become a cycle of spiking blood sugar, causing a blood sugar crash, and leading to more cravings. It is not sustainable! In order to maintain steady blood sugar levels throughout the day it is best to swap refined starches like white bread and white pasta for their whole grain alternative which contains fiber that will keep us full and maintain steady blood sugar levels for much longer. Another way to prevent blood sugar spikes is to create balanced meals and snacks that contain a source of protein, carbohydrate and fat.
Be Choosey with Bedtime Snacks
Going to sleep at later times has been linked to consumption of more energy dense and nutrient poor foods in both children and adults. Watching late night movies calls for a snack, right? A response to eating called the thermic effect of food, or TEF, is the energy required by the body to break down food. The acts of digestion and absorption that occur after eating cause a slight raise in body temperature which can keep the body from fully relaxing into a sleep state. It is best to avoid being overly full right before bed, as this can also cause discomfort. However, restricting the body from food when you feel hungry is not the solution. Honor your hunger cues, but choose a smart snack! When choosing a late-night snack, it is best to have one that contains both a carbohydrate and a protein.
Amino acids are building blocks of proteins. One amino acid called tryptophan is converted to serotonin which is then converted to melatonin. Melatonin is a hormone secreted by the pineal gland of the brain at night to induce and maintain sleep. Carbohydrates make tryptophan more available to the brain, which is why carbohydrate-heavy meals can sometimes make you drowsy. Some examples of protein and carbohydrate rich snacks that could be eaten as bedtime snacks include:
- Cereal and milk
- Peanut butter on toast
- Hummus and pretzels
- Cheese and crackers
- Greek yogurt topped with granola
- Cottage cheese with pineapple or peaches
It is always important to give the body some time to unwind after a long day of action. Typical strategies include dimming lights, engaging in calming activities, having regular sleep and wake times, and having a cool and quiet room. However, staying hydrated throughout the day, eating balanced meals and snacks, focusing on diet quality, and reducing consumption of caffeine and alcohol can all contribute to optimizing your rest!
If you are interested in learning more about how your diet can affect your sleep, consult with one of our Registered Dietitans at Health Loft, virtually via our telehealth platform across the United States or in person in Chicago, IL, by calling us at (312) 374-5399, or by scheduling appointment online. Remember to also check out our Facebook, Instagram, and Twitter pages for more articles on nutrition, physical therapy, and healthy living!
Written By Marissa Gusmao Edited by Alexander Franz Reviewed by Morgan Murdock, RD.
- “Food & Sleep.” National Sleep Foundation, 13 May 2020, www.sleepfoundation.org/articles/food-and-sleep.
- Golem, Devon L, et al. “An Integrative Review of Sleep for Nutrition Professionals.” Advances in Nutrition (Bethesda, Md.), American Society for Nutrition, 14 Nov. 2014, www.ncbi.nlm.nih.gov/pmc/articles/PMC4224209/.
- Lindseth, Glenda, et al. “Nutritional Effects on Sleep.” Western Journal of Nursing Research, U.S. National Library of Medicine, Apr. 2013, www.ncbi.nlm.nih.gov/pmc/articles/PMC5621741/.
- “Nutrition, Exercise & Sleep.” National Sleep Foundation, 17 Apr. 2009, www.sleepfoundation.org/articles/diet-exercise-and-sleep.
- “Surprising Ways Your Hydration Level Can Help or Hinder Your Sleep.” National Sleep Foundation, 1 Aug. 2017, www.sleepfoundation.org/articles/connection-between-hydration-and-sleep.