Food and sleep are among the most basic human needs and are essential to life. You’re probably already aware of how fundamental these two aspects of life are in your overall health. Being denied either of these needs for a sustained period will eventually result in serious medical consequences.
Considering how vital nutrition and sleep are to survival, it makes sense that they would have a very close relationship. The main benefactor of healthy nutrition and better sleep is your brain.
These are two fundamental pillars of mental fitness and can’t be overlooked. Improving both can go a long way toward improving your overall mental health and brain function. Remember that your sleep health and overall health are inextricably linked.
What Does Nutrition Really Mean?
Nutrition refers to the body’s consumption of food and other nourishing materials. These foods contain certain amounts of macronutrients (carbohydrates, proteins, fats, fiber, amino acids, and water), 13 essential vitamins, and various minerals. The body and brain use these nutrients to function properly and are essential to survival.
This process has three major steps:
- Food or drink is consumed, swallowed, and entered into the digestive system.
- The small intestine slowly breaks down the food or drink into nutrients and absorbs them into the bloodstream.
- The nutrients travel throughout the body, aiding energy expenditure, growth, cell repair, and essential bodily functions.
The key to maintaining proper nutrition is ensuring you get all of the essential nutrients. It typically requires healthy eating habits that include several different types of food, including fruits, vegetables, whole grains, beans, nuts, and lean proteins.
A nutritious diet can help provide sufficient energy intake, reduce your risk for obesity and weight gain, improve your immune system, and lower the risk of developing a chronic medical condition.
What Happens When We Sleep?
Sleep is the period when your body and brain functions dramatically slow down so that they can recover. The brain isn’t dormant during this period and will constantly be cycling between two types of sleep: rapid eye movement sleep (REM) and non-REM sleep.
The first several stages of sleep are non-REM sleep:
- The first stage occurs during the transition from being awake to falling asleep.
- The second stage occurs when the heart rate and breathing slow down while body temperature drops.
- The third stage of non-REM sleep is considered deep sleep and is a further descent from the second stage.
Eventually, your brain will enter the fourth sleep stage known as REM sleep. This stage gets its name because your eyes will rapidly move behind your closed eyelids. The brain patterns will appear similar to someone awake, but you’ll still be in a deep slumber.
Heart rate and breathing increase as dreams or nightmares can elicit emotional responses. The body is paralyzed by the neurotransmitters gamma-aminobutyric acid (GABA) and glycine to prevent it from acting out dreams in real life.
The first time you encounter the REM sleep stage will usually only last about 10 minutes. However, each time you enter it throughout the night, the stages will get longer and can last up to an hour. During a regular night's sleep, it’s common to cycle through the sleep stages four or five times.
How Are Nutrition and Sleep Linked?
The food that you eat can have a profound effect on sleep duration and the quality of sleep that you get. Alternatively, frequently encountering poor sleep can impact your food intake and the nutrients you get from it. First, let’s cover how sleep can affect your nutrition.
How Sleep Affects Nutrition
You’ve probably encountered a rough morning after a night of poor sleep. It’s common to wake up tired, groggy, and irritable for a while.
These conditions are known as sleep inertia and are a common part of the human experience. However, if you are constantly waking up this way, it could signify something more serious.
One potential explanation for constantly experiencing sleep inertia is that your body has difficulties regulating the glucose in your blood as you sleep. Insulin is an essential hormone that helps to limit the sugar in your blood.
Frequently experiencing a lack of sleep can increase your body’s resistance to insulin. As a result, you’ll feel more tired in the mornings, increase the amount of fat stored in your body, and become at a higher risk for developing type 2 diabetes.
As if that wasn’t enough, being sleep-deprived can also change your dietary habits via hormones. It’s common to develop a bigger appetite when constantly sleep-deprived because of a hormonal imbalance. Making food choices that aren’t sleep-promoting can also affect your sleep quality.
Leptin levels (the hormone that tells you when you’re full) will start to drop, while ghrelin levels (the hormone that stimulates your appetite) will increase. The combination of these metabolic factors will make you feel hungry more often and need more food to satisfy your appetite.
How Nutrition Affects Sleep
The effects that nutrition has on your sleep are much easier to notice. Chances are likely that you’ve overdone it and eaten too much at a Thanksgiving dinner or buffet (hello, tryptophan).
Postprandial somnolence, or a food coma as it’s more commonly known, is the feeling of intense fatigue and drowsiness after eating a large meal. Normally, these meals are very high in carbohydrates, saturated fat, or protein.
On the other hand, eating food loaded with sugar or caffeine can have the opposite effect and keep you awake for much longer. Even if you ingest these foods earlier in the day, they can still disrupt your circadian rhythm.
You’re likely to experience daytime sleepiness as the effects of the caffeine or sugar wear off. A quick nap is all that it takes to disrupt your sleep pattern during the night.
One study found that sleep disorders and sleep disturbances could be traced back to certain nutritional deficiencies. The lack of vitamins A, C, D, E, K, calcium, and magnesium have all been linked to insufficient sleep. These deficiencies most likely harmed hormonal pathways that play an integral role in helping the participants fall asleep and stay asleep at night.
Which Foods Affect Sleep the Most?
The key to maximizing your sleep quality is to focus on a diet that’s high in fiber and contains lots of vegetables, fruit, whole grains, and low-fat protein. In particular, you should look for B vitamin-rich foods as they are the most responsible for regulating melatonin.
If you decide not to follow a diet featuring these foods and nutrients, then you should at least take care to avoid the following foods:
- Spicy Foods. These fiery dishes and sauces can contribute to heartburn and raise the body temperature, keeping you tossing and turning throughout the night.
- Fatty Foods. Fried foods or dishes that are heavy with butter, cheese, and fatty cuts of meat can make your stomach feel uncomfortably full and disrupt your sleep.
- Acidic Foods. Even some “healthy” foods such as onions, garlic, and tomatoes can trigger acid reflux, preventing you from enjoying a peaceful night of sleep.
- Alcohol. While it is true that alcohol can “help” you fall asleep faster, it severely disrupts the sleep cycle and limits the overall amount of time you experience REM sleep and slow-wave sleep.
- Caffeine. Having a cup of coffee or two in the morning is fine, but try to limit your caffeine intake after midday so that you don’t delay your circadian rhythm.
How Much Sleep Do I Need Each Night?
The amount of restorative sleep you need each night will change based on age. For instance, newborns need between 14 and 17 hours of sleep daily to develop and grow properly.
As you develop and age, the required total sleep time will gradually decrease. Infants need 12 to 16 hours of sleep, toddlers need 10 to 14 hours, and children/teenagers need eight to 12 hours.
By adulthood, you should get between seven to nine hours of sleep every night. If you cannot get at least seven hours of sleep every night, you are at high risk for sleep deprivation, poor sleep quality, and more sleep disruptions. You should immediately take steps to improve your sleeping schedule or potentially develop serious medical conditions.
Stay Sharp With a Healthy Diet and Proper Sleep Schedule
It’s common knowledge that eating a poor diet quality and failing to get enough sleep can quickly lead to physical and mental health problems. How closely diet and sleep are related might not be as well known.
Eating a poor diet can cause you to develop sleeping problems, making your diet even worse. It’s a vicious and dangerous circle. The only way to break this circle is to ensure you eat a healthy diet and get enough sleep every night.
It might take a little work, but your brain will appreciate your efforts. A healthier diet and more consistent sleep can lead to improved brain function, an elevated mood, and lower the risk of developing a medical condition.
Talk to your healthcare provider about any diet changes you are thinking of making, or reach out to a sleep medicine specialist if you are concerned about your sleep quality. Why go through life tired, groggy, and irritable when you can experience benefits like that?
Sources:
How Much Sleep Do We Really Need? | Sleep Foundation
Effects of Caffeine on the Human Circadian Clock In Vivo and In Vitro | PMC
Alcohol and Sleep | Sleep Foundation
Food and Gastroesophageal Reflux Disease | PUBMED
Dietary Fat Intake and Functional Dyspepsia | PMC
Spicy Food Consumption and Risk of Uninvestigated Heartburn in Isfahani Adults | PUBMED
B Vitamins and the Brain: Mechanisms, Dose and Efficacy—A Review | PMC
Meal Composition and its Effect on Postprandial Sleepiness | PUBMED
Sleep & Glucose: How Blood Sugar Can Affect Rest | Sleep Foundation
Habitual Sleep Deprivation is Associated with Type 2 Diabetes: A Case-Control Study | PMC
Waking Up is the Hardest Thing I Do All Day: Sleep Inertia and Sleep Drunkenness | PMC
The Science of Sleep: Understanding What Happens When You Sleep | Johns Hopkins Medicine