Sleep, Diet, Exercise: How They Are Connected

Written by
Purple Staff
Last Updated
September 10, 2022
min read

Our mental and physical health is affected by several factors, but doctors always point to three as having a significant impact: sleep, diet, and exercise. Is one of these more important than the other? What is the effect of each one on our health?

Read our guide to learn about how having good or bad sleep quality, diet, and exercise are connected. In this guide, we'll also discuss how to improve sleep quality by changing your food intake and getting regular exercise.

The Role Of Diet, Sleep, And Exercise In Health

Diet, sleep, and exercise is all part of maintaining a healthy lifestyle. Here's how each one plays a factor in your general well-being.


A healthy diet gives us the minerals and vitamins we need to maintain a healthy body. Food is fuel, and energy helps us fight off infections and do our daily activities. 

A good diet should ideally include the five basic food groups:

  • Vegetables and legumes
  • Fruit
  • Grains and cereals (e.g rice and oats)
  • Lean meat, poultry, eggs, fish, nuts, and seeds
  • Milk, cheese, yogurt (or alternatives for those with dairy allergies)

Each of these groups contains important nutrients for physical growth, mental health, and warding off fatigue. Make sure that all of these groups are present in your daily meals!


Research has consistently recommended that the average adult should sleep a minimum of seven to nine hours a night. Despite this, nearly a third of Americans get by on less than six hours a night. This reduced sleep quantity can make us feel fatigued and unfocused.

Sleep deprivation has long-term consequences on our health, such as increasing the risk of developing strokes and heart attacks. It also affects our mental health, with studies showing a strong link between mental health issues like depression and a lack of sleep. 

Conversely, getting enough quality sleep can help us recover from the day's exertions and improve how we manage stress.


Getting regular exercise is highly recommended by medical experts for better physical and mental health. Exercise strengthens our cardiovascular system, improves muscle strength, and reduces feelings of depression and anxiety.

Overall, more physical activity has been shown by research to increase our life expectancy and delay the onset of 40 chronic diseases. The CDC recommends that adults should have at least 150 minutes of moderate physical exercise a week for a fitter, healthier body.

Which Is Most Important: Diet, Sleep, Or Exercise?

None of these three factors are more important than the others when it comes to having a healthy body. A bad diet can have a negative effect on your sleep quality and keep your body from getting the fuel it needs to maximize exercise gains. Poor sleep has also been proven to increase the risk of sports injuries during exercise.

A lack of exercise can make it more likely for people to gain weight and, consequently, develop sleep problems like sleep apnea. These can interrupt your bedtime and prevent you from falling into the deep sleep your body needs.

Conversely, improving one of the three can have a positive ripple effect on the rest. A healthy diet can improve exercise results and make it easier for you to sleep. Good sleep boosts workout recovery and can reduce cravings for junk food. Regular exercise makes sleep more restful. 

How To Improve Sleep Through Diet And Exercise

If you're suffering from poor sleep, you can change your diet and exercise routine to improve sleep quality. Here are some easy changes you can make to get more hours of sleep!

Avoid Caffeine

Caffeine is a stimulant used by many people to stay up and boost their productivity. However, it also disrupts your sleep patterns, can make it hard for you to fall asleep, and even worsen insomnia.

Even in the morning or afternoon, your body will still be processing the caffeine in your coffee or energy drinks. One study found that consuming caffeine even six hours before bedtime can reduce your sleep quantity by one hour. 

Make sure you get enough rest by reducing your caffeine consumption or consuming it earlier in the day.

Have A Healthy Diet

A poor diet may be the reason why you're getting inadequate sleep! Unhealthy eating can cause weight gain, which is one of the reasons why people develop obstructive sleep apnea and keep getting their sleep interrupted. Other studies have found that not getting enough vitamins and minerals like magnesium, calcium, and vitamin A are closely linked to sleep curtailment.

Add more leafy greens to your diet, cut out the junk food, and eat more whole grains and fruits. These small steps may be the key to getting better quality sleep!

Move Your Body

Adding more physical activity to your day may help you get more rest. Research has shown that getting moderate exercise can reduce sleep complaints like insomnia in patients.

The jury's still out on the optimal time for exercise, so just listen to your body and adjust your workout days to your needs. If you're very busy throughout the day, you can add more movement by brisk walking or taking the stairs instead of elevators whenever possible.

Avoid Late Night Snacks

Eating late at night means your body will have to work to digest your snacks, keeping you from falling into a deep, restful sleep. Make sure you have a gap of at least two hours between your bedtime and your last snack or meal.

Go Outdoors For Vitamin D

Studies show a link between Vitamin D levels and sleep quality. Vitamin D deficiency has been found to cause sleep problems and reduce sleep quality. Higher levels were found to increase restfulness.

While there isn’t a consensus on the exact reason why, it may be because Vitamin D is involved in the production of melatonin, a hormone that regulates our internal body clock. 

Put on some sunscreen and get a healthy amount of sun exposure to get more Vitamin D. It just might help you sleep better!

Try Yoga And Stretching

If you're struggling with short sleep duration, try light forms of exercise an hour or so before bed. Low-impact exercises like yoga, pilates, and stretching can help you fall asleep faster and sleep more deeply. It can even interrupt the incidence of sleep disruptions and help your body maintain its circadian rhythm, a.k.a. its internal body clock.

Frequently Asked Questions On Sleep, Diet, And Exercise

Does exercise reduce the need for sleep?

Increased physical performance does not reduce the need for sleep. However, physical activity can reduce the incidence of sleep problems like insomnia and help you get restful sleep.

Does sleep count as exercise?

No, sleep does not count as exercise. However, sleep makes it possible for us to reap the benefits of exercise. When we work out, it's typically to achieve specific goals like increasing our endurance or building muscle mass. This process needs sleep to work because it's when we sleep that our muscles grow and repair themselves.

Can dieting affect sleep?

Yes, dieting can affect your sleep. Eating late at night before bedtime can make it hard for your body to fall asleep. Not getting enough calories because of a punishing diet may lead to hunger pangs and cravings that also keep you awake at night.

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