If you’re sleeping too much or not enough, you may want to take a look at how much (or how little) light you’re exposing yourself to every day. Our bodies are very sensitive to light, as it is the light that helps to regulate our sleeping and waking cycles. Sleep is regulated by two body systems: sleep/wake homeostasis and the circadian biological clock. While both internal and external cues can affect these cycles, the most powerful external cue is light.
Our eyes are equipped with light-sensitive cells in our retinas that regulate our sleep patterns according to how much light they detect. The single biggest change to our natural sleeping cycles occurred with the development of the light bulb at the turn of the century. Exposure to more light in the evening caused a shift to later bedtimes. Shift workers fight the natural rhythm, which significantly alters sleep-wake patterns leading to increased sleepiness, impaired attention, impaired performance and alterations in mood. Disruption to sleep-wake patterns has been shown to increase the likelihood of fatigue-related workplace and driving accidents.
Increasing reliance on mobile devices – which many of us sit up with while in bed – has been causing a further disruption in our regular sleep cycles. If you are looking to get a sound sleep, turning off the lights and putting down the phone well in advance of bedtime could help you rest easier.
Exposure to light can also work in reverse and make it easier to get out of bed and make that morning meeting on time. Regular exposure to full-spectrum light can also leave you feeling invigorated throughout the day. Research conducted by Rensselaer Polytechnic Institute has substantiated a slew of benefits from this kind of light, and also debunked a few marketing myths. The reality is, the quality and amount of light can make a psychological and physiological difference.
This is why we often feel so much better when the sun is out. Investing in an alarm clock that triggers a warm light to turn on as you wake, or getting up and immediately turning on all of your lights, can trick your body into beginning its wake cycle. If you work in a dim home or office, investing in lamps that emit a full spectrum of light that mimics sunlight – like a Microsun lamp – can so also help reinforce these “wake up” cues throughout the day.
Do you have more questions about the effect of light on our health and moods? Find out more about the science of light here.
