By Myra Campbell
As a natural biological function, many people take it for granted. That is until they don’t get enough of it. Lighting impacts the body’s ability to fall and stay asleep. Smart illumination in the home can contribute to not only better sleep but wakefulness in the right times and places.
Light and Circadian Rhythms
Circadian rhythms control the sleep-wake cycle, and they’re heavily influenced by natural light. The body adjusts to feel tired as the sun goes down. This light exposure controls the release of sleep-inducing hormones like melatonin. The body relies on these rhythms to maintain regular daily cycles and events like sleep that need to happen at roughly the same time every day. Artificial light can cause the body to get confused as it can stimulate the brain during the night when the body naturally wants to be asleep.
Light, Eyes, Brain
As the receptacles of light, the eyes play a pivotal role in establishing healthy circadian rhythms.
If the eyesight begins to deteriorate, so too can the ability to regulate circadian rhythms. Poor eyesight often contributes to sleep disturbances in the elderly. Their brains have a hard time keeping a consistent circadian rhythm without enough light.
The eyes have three kinds of receptors. Each serves a purpose, but the ganglion cells absorb light and send messages to the part of the brain that regulates the sleep-wake cycle. Ganglion cells are particularly sensitive to the blue light emitted from energy-efficient LED bulbs and electronics like televisions, laptops, and smartphones.
Exposure to this kind of light close to bedtime can send the brain conflicting signals. While it may be dark outside, the brain receives light that triggers the “awake” response, resulting in lost sleep. Teens, in particular, are more susceptible to the effects of blue light as their developing brains stay awake longer than adults even if they have the same amount of exposure. Teens already experience a shift in their circadian rhythms due to hormonal changes, which makes it difficult for them to get up early in the morning. Add on too much exposure to blue light, and you’ve got sleep-deprived teens on the road, in classrooms, and in the workplace.
Creating Lighting that Supports Better Sleep and Wakefulness
Lighting can have a big enough impact on sleep quality that it’s worth taking into consideration when lighting a room. Blue lights should be removed from the bedroom. In areas of the home that need wakefulness like the kitchen, office, or study area, high-efficient LED bulbs would be appropriate. That’s also the right place for electronics. Charging stations in the kitchen can help keep smartphones out of the bedroom. Traditional, incandescent bulbs give off red light, which doesn’t interfere with sleep, making them the right choice for the bedroom.
Sleep Smart, Sleep Dark
Even natural light filtering through sheer curtains can make it difficult to sleep. The optimum sleep conditions include:
Complete Darkness: If light pollution comes into the bedroom, use blackout curtains or blinds to eliminate as much light as possible. Use nightlights low to the ground for visibility during nighttime bathroom visits.
Comfortable Mattress: The amount of light won’t matter if a bed is lumpy or sagging. An appropriate mattress allows the body to relax and enter the deepest levels of sleep.
Cool Temperature: The body temperature falls during sleep. A room kept anywhere from 60 to 68 degrees can comfortably support a lower body temperature.