'Lights out!': Why sleeping in 'complete darkness' is beneficial for you and your baby

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Light has dramatic effects on sleep, influencing our circadian rhythm, melatonin production, and sleep cycles.
Light has dramatic effects on sleep, influencing our circadian rhythm, melatonin production, and sleep cycles.

Lights out is a well-known phrase, indicating it is bedtime, however, there is more to it than that.  

Exposure to light is one of the most important factors when it comes to sleep.  Most people know it is easier to sleep when it is dark, but it is important to know that the link between sleep and light exposure goes much deeper.

Before electricity, humans woke and slept in sync with the rising and setting of the sun, but now there are lights in our homes, electronics and light pollution outside have made the relationship between light and sleep much more complex.  Light has dramatic effects on sleep, influencing our circadian rhythm, melatonin production, and sleep cycles.  

Also see: 'It is discipline, not punishment': A mother's tips on how to avoid a bedtime blow-up

Circadian Rhythm: Connected to a 'master clock' in your brain 

Circadian Rhythm works by helping to make sure the body's processes are optimized at various points during a 24-hour period.  Circadian rhythms throughout the body are connected to a master clock, sometimes referred to as the circadian pacemaker – located in the brain.  

During the day, light exposure through the eyes causes the master clock to send signals that generate alertness and help keep us awake and active. 

As night falls, the master clock initiates the production of melatonin, a hormone that promotes sleep, which then keeps transmitting signals that help us stay asleep through the night.  

Circadian effects vary based on the type of light and the duration of exposure. While prolonged light tends to be impactful, even short periods of artificial light can affect circadian rhythm.

Melatonin production: Why you want as much darkness 'as you can handle'

Melatonin is a hormone made by the pineal gland located in your brain.  It helps your body to know when it is time to sleep and time to wake up. 

Your body makes more melatonin at night – it increases once the sun starts to go down and decreases in the morning as the sun comes up.  The amount of light you get during the day together with your body clock determines how much melatonin you produce.  

It goes without saying, then, that we need to make sure little ones have enough melatonin when it is time to sleep.

Light inhibits the secretion of melatonin. "Even if you doze off, light can be detected through your eyelids and your brain won't produce melatonin if it's confused between night and day," says Joyce Walsleben, Ph.D., associate professor at the New York University School of Medicine.

"You want as much darkness in your bedroom as you can handle," she says.

Also read: 'Like training wheels for your emotions': Why your baby could benefit from having a blanky

Sleep cycles: 'integral to maintaining a balanced mental and emotional well-being'

Sleep cycles are a combination of different sleep stages (REM and non-REM sleep).  

When exposed to light at night, it disrupts the transitioning between sleep cycles, reducing the quality of sleep.  When exposed to too much light it will cause repeated awakenings, interrupting the sleep cycle and reducing time spent in deeper, more restorative sleep stages.  

Studies suggest that a healthy sleep cycle is integral to maintaining a balanced mental and emotional well-being. If your quality of sleep gets affected due to even a small amount of light, then you run the risk of having sleeping issues, which are well-known for causing a range of emotional problems, including depression.

How dark should it be and how do we achieve that?  

Have you ever visited a hotel, guesthouse or lodge where they have block-out curtains? 

Most people can recall how well they slept in complete darkness.  This is not only beneficial for good quality of sleep, but helps us to fall asleep easier and stay asleep.  

Teaching babies and children to have good quality sleep is so important and one of the most important (and easiest) ways to do so is to make their room dark.  

When closing the curtains during the daytime, it should mimic the night.  Not only does it signal the brain it is time to sleep, but it helps little ones to fall asleep without any distractions.  

Children’s eyes are anatomically slightly different, they do allow in more light, which is why it is even more important to make sure they sleep in a dark environment most of the time.

As a mom myself, I know every parent wants the best for their children and we will do what it takes to help them sleep better (I am sure I don't have to explain to you how important sleep is).  So why not take a few minutes to do a darkness check and if needed make the changes – it will be worth it.

Must see: WATCH | Two in three parents of newborns say they have no clue what they're doing most of the time


Block-out curtains and blinds: These are a great long-term investment. To test whether curtains are 100% block out, take your cellphone light and shine it through the fabric – if you can see the light, they are not 100% block-out curtains.

Make sure the curtains cover the whole window and no light is shining in on the sides.

An easy, cheap and effective way of blocking out light is to cover your windows with black bags, brown paper, cardboard, or even aluminium foil.

Block-out travel blinds have suction cups and stick to windows, which is an easy and effective way to sleep better when traveling! 

Take 5 minutes and switch off the lights in the room: Go and stick Prestik or double-sided tape on all small LED lights in the room – eg monitor light, aircon light, humidifier light, etc.

Keep nightlights low and on the ground so that they are not shining directly into a child's eyes.

Dim all household lights one hour before bedtime or keep toddlers in their rooms, as coming into bright light before bedtime can affect their melatonin production.

Another question one might ask is:  does this mean my child won’t be able to sleep unless it is completely dark?  The answer is no.  Darkness helps to provide good quality and longer sleep.  As most families spend at least 95% – 98% of their time at home, it is a small change to make to ensure great sleep when sleeping at home.

Republished with permission. Find the original article at Good Night Baby.


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