Do You Burn Calories While You Sleep?

Since your body is always in a state of activity, even while sleeping, it makes sense that you would burn calories while sleeping. Your beating heart, respirations, and even body temperature influence calorie burn while at your least active state, but exactly how many calories are we talking about?

Let’s take a look at what happens to our bodies while we sleep and what factors affect calorie burn to help us maximize effects, and create a healthy, productive rest.

What Happens to Our Bodies While We Sleep?

Even though we spend close to a third of our lives asleep, very few people are aware of what their body is doing during this time. In short, your body is repairing itself, strengthening both your physical and mental states, storing memories, applying healing processes, and giving the immune system a workout.

As your body cycles through the sleep stages, your body lowers its core temperature, lowers both respiration and heart rate, and increases blood flow through the body for this regenerative process to occur.

Your physical shape plays a huge part in this process as well, and so each person is very different in how their bodies react to and heal from their day to day activities while sleeping. Environmental factors are also part of the process and can either hinder, or support a healthy rest as well.

Does Sleeping Burn Calories?

Your body is in a constant state of metabolic burn, affected by various factors. While sleeping the average calorie burn is considered to be around 50 calories per hour, but may be higher or lower depending on these factors.

Since it is suggested by the Center for Disease Control that adults receive 7 hours of sleep each night, you could realistically be burning 350 or more calories during this time. If you have an idea of your Basal Metabolic Rate (BMR), you can better figure what your body may be burning each hour at rest.

You might want to read this: How Many Calories Do Your Burn Sleeping?

Factors That Affect Calorie Burn

Your BMR is a measurement that determines the number of calories needed to exist without any external influences – such as movement or exercise. It is dependent upon gender, body weight and height, as well as age. The BMR will decrease with weight loss, as well as with age – so there is a lot of variation from one individual to the next.

• Age

Metabolism is determined by age, weight, and heart rate. As you age your metabolism goes down in relation to weight and body function.

• Height, Weight, Gender

The larger a person, the more calories needed to function properly. Taller and heavier people require more calories, so their metabolic rate has a tendency to be higher as well. Gender also affects metabolism since biological men almost always have a higher proportion of muscle mass and thus a higher proportion of regeneration activity.

You might be interested: The Link Between Sleep and Weight

• Fitness Level and Exercise

Muscles burn more calories and so those who are fit and exercise regularly are burning more calories even at rest. Strength training and weight lifting in particular help increase the metabolic rate, but any exercise and movement will burn calories. The higher the heart rate, the higher the burn, and the longer the activity, the longer you will continue to burn calories even after you stop moving. This definitely can affect calorie burn at rest, especially if you had worked out closer to your bedtime.

• Diet

The energy needed to digest, absorb, and dispose of ingested nutrients defines the thermic effect of food (TEF). 10 – 15 % of calories are used to metabolize consumed food, but some macronutrients are better at doing this than others. Adjusting your diet to maximize this effect isn’t difficult if you pay attention to the following:

Macronutrient Calories/Gram TEF %
Fat 9 0-3%
Carbohydrate 4 5-10%
Protein 4 20-30%

• Alcohol and Caffeine

Caffeine is a stimulant and works to increase calorie burn due to the increased movement you may participate in, as well as the effect it has on metabolic increases through a thermogenic effect.

Alcohol is generally energy-dense but has a low TEF and can slow down your metabolic rate. It also can disrupt your sleep patterns which in turn may interrupt your body’s response to calorie burn.

• Hormones, Medical Conditions, and Prescription Drugs

Your body is constantly producing and reacting to various hormonal levels. Hormones can directly affect metabolism, and work to speed it up, or to hinder it. Hormones can also react to hunger, slow down your TEF rate, or react to a lack of sleep – tricking your mind into thinking you are hungry which often results in a higher caloric intake.

Pregnancy, breastfeeding, and menopause can create dramatic differences in calorie burn rates. Medication is also often a factor in hormonal response and body response to your metabolism.

Wrapping It Up

Your body burns calories while sleeping, but the exact number is dependent upon many factors that are specific to your own body type and condition. To get a rough idea of how many calories your body needs at rest during a 24-hour period, you can figure your basal metabolic rate.