Up all light? The Impacts of Light Sensitivity on Quality of Sleep

Are you more of a night owl or a morning bird? Some of us are most productive in the wee hours of the night, while others enjoy meditating to the sunrise. Light is important to humans, greatly impacting our hormones and our mood. In the winter months, for example, the lack of sunlight is a factor behind winter blues and seasonal affective disorder. Light also plays a leading role in our sleep and our sleep schedules.


How does light impact sleep?


Most people find it hard to fall asleep with all of the lights on, and there is science behind this. Our circadian rhythm, controlled by the brain’s circadian pacemaker, is our internal 24 clock that processes sleep.  When someone sleeps when it's dark out, and is awake and active during natural sunlight hours, the circadian rhythm will react accordingly, helping you stay alert during hours with sunlight and feeling tired when it’s dark. This means that even a little light exposure during sleeping hours can signal the brain, which tells the rest of the body and organs that it's showtime, resulting in interrupted and/or poor sleep. 


“The hormone of darkness,” or melatonin, is a critical hormone for sleep, as it promotes drowsiness and rest while keeping your circadian rhythm regular. It naturally occurs in the pineal gland and requires darkness to produce. Melatonin levels begin rising two hours before bedtime, so exposure to light (natural or artificial) can halt or slow down the production of melatonin.


Exposure to light is significant to the quality of sleep, because light stimulates the brain and body to be alert. Research highlights that insufficient darkness throughout the night can result in ten or more minutes less sleep, and the feeling of fatigue and confusion the following day, impairing concentration.

Blue light from phones/televisions, led lights and even street lights (People who live in cities of more than 500,000 people are exposed to 3-6x brighter street lights which can disrupt sleep, than those in rural areas) will impact our bedtimes, alerting the brain to be awake.


Darkness matters

Darkness matters. This goes back to caveman days when hunters and gatherers were unable to work and provide for their families when the sun was down. It wasn't until the discovery of electricity in the 20th century that humans had to create or seek out darkness. Further, our bodies require vitamin D, only available during sunlight hours, to regulate our mood and help with bone health. As mentioned above, the pituitary gland in our brain only starts to secrete melatonin with darkness. 


As such, it is best to sleep in complete darkness and we need to help by setting the scene, as research tells us that closed eyelids are not enough to block out all external light. 


How to set the scene for a dark bedroom?


  • Gravity’s weighted eye mask: Wear Gravity’s scientifically proven eye mask to bed to make even the brightest room pitch black (perfect if your partner's routine is different to yours!) The mask provides between .75 to 1lb of pressure that increases serotonin and melatonin, helping us to relax while pushing away cortisol (the stress hormone). Plus, the masks are micro-plush with imitation cashmere with an adjustable velcro strap, so they are super comfortable to wear all night.
  • Blackout blinds: Especially for us city gals! Invest in blackout blinds to prevent any light coming in from outside.
  • Limit all technology before bed: I know, I know. We all know it's bad but it's a hard habit to break! All tech produces blue light, which basically keeps your brain on high alert. If you are a TV pre-bed person, ensure it's at least 6 inches away.
  • Limit light nights to the hallway: Limit nightlights to the hallway and use a red bulb. Red is considered a 'long wavelength light,' which has been studied as less disruptive to sleep than other light wavelengths.
  • Add lights to your sleep routine: About two hours before bed, dim the lights or turn them off and use gentle lamps or candles.  This will invite your body to start its natural sleep routine.


 A night of restful sleep requires darkness. When it is dark, our body understands that it is now time to take a break. So whether you prefer nights to morning or vise versa, you should strive to create a sleeping environment that is conducive to darkness, in order to encourage quality sleep.