Is Sleep Loss Slowing Down Your Metabolism?


Is sleep loss bad for your metabolism?


Can sleep loss affect your metabolism, cause weight gain and even affect your body's ability to store fat? In a recent study I found... yes it can!

First, let's look at something important that is responsible for your natural sleep cycle, and this natural cycle is called the circadian rhythm. 

Circadian rhythm is often referred to as the body’s internal clock, also known as the natural sleep-wake cycle.  Circadian rhythm is responsible for allowing us to get tired at night when the sun goes down, and waking us up in the morning when the sun rises. The environment and seasons can help the body’s natural circadian rhythm, or hinder it, depending on where a person lives on the earth. Obviously, if someone lives in Alaska, they’ll have a harder time falling asleep when they are “supposed to” during the summer, since there is daylight almost 24 hours a day. The same would be true for the winter months, when it is mostly dark.

Have you ever noticed that during the winter months, when the sun sets earlier, you also get tired earlier? This is because the body is very attuned to picking up cues from it’s environment.

Anything that keeps us up throughout the night, whether it’s something in our control, like working an overnight shift, or something out of our direct control, like insomnia, will disrupt the body’s natural circadian rhythm, bringing a potential onslaught of physical, mental and even emotional disruptions.

It’s important to know that when we sleep, hormones are secreted that help optimize the body. If the body’s sleep-wake cycle is disrupted, this means that the hormone release is also disrupted, which will lead to health problems down the road.


What chemicals get released during sleep and why are they important?


What chemicals get released during sleep and why are they important?

Melatonin: this chemical helps determine that it is time to go to sleep. It can also be taken as a supplement to help you get sleepy. It’s produced in the pineal gland and is released with increased darkness. 

Growth Hormone: this chemical is produced in the pituitary gland and is essential for tissue repair and growth.

Oxytocin: also known as the “love” hormone, because it is released during child birth, breastfeeding, hugging, orgasm, and even sleep! This chemical peaks after 5 hours of sleep, which is another great reason to get that sleep!

Antidiuretic Hormone: also known as ADH, this hormone is produced in the pituitary gland and prevents the production of dilute urine. It tells your kidneys how much water to conserve and also regulates the amount of water in your blood.

Prolactin: this chemical is produced in the pituitary gland and is involved in over 300 functions in the body, including metabolism, lactation (if you’re a breastfeeding mama) and the immune system.


Which hormone will wake me up?

Now, you may be asking... which hormone will wake me up?

This hormone is… cortisol!

Cortisol is the chemical that helps wake you up! Yes, you may associate this as the “stress hormone”, but cortisol isn’t all bad, all the time!  

As you can see, when the body isn’t getting enough sleep, the brain won’t be able to release enough of these important chemicals, which may ultimately create health problems in the long run.

How lack of sleep can affect your metabolism:

Now, onto the good stuff!

It’s obvious that with a lack of sleep, or constant sleep disruption, the body won’t be able to work as efficiently. It’s clear that if the brain isn’t producing enough chemicals during the sleep cycle, it will affect how your body works during the wake cycle. 

Now, just how does this affect the metabolism?

A recent study shows “sleep loss increases the risk of obesity through a combination of effects on energy metabolism.” 

What does this mean exactly? It means that lack of sleep, and lack of good quality sleep, is related to changes in appetite, metabolism, motivation, physical activity and even a combination of all of those factors.  Even though the underlying cause is still not clear, the fact that doctors have found a link between sleep loss and weight gain is huge!

One particular study I found suggests that sleep loss correlates and even favors weight gain in humans (this specific study was performed with human models, and not animal models). 

The study took a group of adults, and measured the behavioral, physiological, and biochemical responses to food, following sleep deprivation. The study showed that when a person was sleep deprived, they were more likely to prefer large portions of food, consume more calories, experience more pleasure from food, exhibit signs of increased food-related impulsivity, and also expend less energy. 

In short, this means that less sleep could result in increased hunger, larger portions, and more intense cravings.

As we all know by now, the nasty equation for weight gain is an increase of calories in, and a decrease of calories out. What is a calorie after all? It’s simply a measurement of energy.

Aside from behavior, what happens beneath the surface is just as fascinating. The study group’s physiological factors showed that sleep loss affects hormonal balance; particularly the hormones that are directly linked with feelings of hunger and fullness. Besides that, there was also an imbalance of gut bacteria, which is responsible for digestion, nutrient absorption and the metabolism; and a reduced sensitivity to insulin, which in turn can lead to other health conditions such as type 2 diabetes.

As a conclusion to this, it may be suggested that improving sleep could be a simple and promising lifestyle change to reduce the risk of future weight gain.

HOLLA!!! (I love me some sleep!!)

How do you sleep, in general? Have you noticed a direct link with hunger or cravings when you get less sleep? I would love to know!