Sleep plays a vital role in optimal health and performance. Getting enough sleep can affect your mental health, safety, and physical health. Sleep is measured by many factors but to keep it simple, we will look at sleep duration and sleep quality. Sleep duration is the amount, in hours, of undisturbed sleep. Sleep quality is measured by slow wave sleep and rapid eye movement. Slow wave sleep happens when you are in deep sleep and the body is building up physical and mental energy. Certain functions decrease, such as brain and muscle activity, and the body can actually rest. Rapid eye movement occurs when the body is in the REM stage of sleep. This is the stage of sleep when you are actively dreaming. Both slow wave sleep and rapid eye movement occur more often when undisturbed sleep duration is longer. In this article, we will focus on how sleep affects physical health and how nutrition plays a role in this relationship. Studies have shown that individuals who tend to have less than optimal sleeping patterns, less than 7 hours of undisturbed sleep, tend to be at higher risk of becoming obese. Other studies have shown that sleeping less than 8 hours a night can increase your chances of injury by 70%.¹  Now that we have some background on sleep we will be reviewing how carbohydrate and healthy fats play a vital role in sleep.

Carbohydrates and Sleep

First, we will review a study which looks at the relationship of carbohydrate choices and sleep quality. The study was done among Japanese women in which a lifestyle questionnaire was used to determine eating and sleeping habits.  Findings show a strong correlation between carbohydrate choice and sleep quality. Before we go any further, let us briefly review the different types of carbohydrates. As you may know, there are two types, or categories, of carbohydrates. One category includes fast acting carbohydrates, which are foods that are high in sugar and low in fiber (i.e sugar-sweetened beverages, white grains, etc). These usually provide a burst of energy, but then come with a crash shortly after. The other category includes long lasting carbohydrates. These are high in fiber and low in sugar (whole grains, legumes, etc). The energy provided from these foods are usually sustained and distributed evenly throughout the day.  The study found that individuals who ate fast acting carbohydrates throughout the day, such as high sugar foods and noodles, usually had poor sleep quality, which means less slow wave sleep and rapid eye movement. However, those who had slow-digesting carbohydrates, such as vegetables and high fiber foods, had better and more frequent deep sleep and rapid eye movement.² Not only does the type of carbohydrate affect sleep quality but also the type of fats consume can be a factor in your overall sleep quality.

Click Here to read our past article on fiber and the importance of including fiber in your diet.

Fat and Sleep

Next, we will look at how healthy fats play a role in sleep quality. The Mediterranean diet is one known for promoting healthy fats. This eating lifestyle includes more fish and plant fats, as opposed to beef and animal fats, which is the standard for the American diet. Fish and plant fats contain omega fatty acids that possess an anti-inflammatory effect. Beef and animal fats are high in saturated fat, which can turn on inflammation. Have you ever put butter and olive oil in the fridge? You may notice that butter stays hard and the olive oil stays in a liquid state. The same happens in your body. The butter “hardens” in your blood vessels while the olive oil gets transported throughout for energy use. So how does this relate to sleep? Just like with the carbohydrates, the same study found that those on the Mediterranean Diet, and eating healthy fats regularly, had better sleep quality. Those with diets higher in fats that cause inflammation tend to have a higher occurrence of insomnia (inability to sleep).²

In conclusion, everything we put in our body affects our sleep and energy level. If you have trouble sleeping it could be your diet as a whole, certain foods you are eating, or even what you are doing leading up to when you go to bed. Along with what we mentioned in this article, here are five ways you can help improve your sleep:

  1. Establish a sleep schedule, and stick to it…even on weekends
  2. Sleep in a cool dark room without any light
  3. Refrain from looking at your phone or computer right before bed
  4. Sleep on a comfortable mattress and pillow
  5. Get outside, exercise daily and get some Vitamin D exposure. Vitamin D deficiency has been shown to decrease sleep quality.


  1. Milewski, Matthew D., et al. “Chronic lack of sleep is associated with increased sports injuries in adolescent athletes.” Journal of Pediatric Orthopaedics 34.2 (2014): 129-133.
  2. St-Onge, M. P., Mikic, A., & Pietrolungo, C. E. (2016). Effects of diet on sleep quality. Advances in Nutrition: An International Review Journal, 7(5), 938-949.