How does watching TV or using my phone right before bed affect my sleep?
Melissa Lipford: Watching TV or using your phone right before bed can impact your sleep in several ways. Social media, games, and shows/movies engage the mind, at a time when it should be winding down. Stimulating digital content makes us want to stay up later (just one more episode) and delays our ability to relax and fall asleep. Even if you fall asleep with the TV on, the ongoing sounds and dialogue can disrupt sleep and awaken you.
Try limiting screen time to at least an hour before bed. Instead of falling asleep in front of a screen, try establishing a relaxing bedtime routine. This could include pre-sleep activities like taking a warm bath or shower, relaxation exercises, or reading. You may find these steps make your sleep deeper and more restful.
Maya Ramagopal: Electronic screens like smartphones and TVs emit blue light. It is a short wavelength light, that delays or reduces the production of melatonin. A high level of melatonin is needed for sleep onset. Blue light can also decrease the amount of time spent in slow wave and REM sleep, two sleep stages that are vital for cognitive functioning.
Matteo Cesari: Natural light is brightest at midday, and darkest after sunset. It is measured in lux, ranging from 130,000 at the brightest point to 30 at night. The circadian rhythm functions around this type of light schedule. Awake periods coincide with the brightest midday light, and sleepy periods are associated with low light. Artificial light and light emitted from screens range somewhere between the two extremes. When they are used after dark, there is a potential for circadian disruption.
Robert Thomas: I have stopped recommending “no screens before bed” because patients will not stop screen use. It makes sense to adjust screens to dark mode, lowest intensity, and avoid intense material. For my most “disobedient” patients, I have recommended low doses of melatonin at 8 PM. This has been successful in countering bad light behaviors around bedtime. If you cannot beat them, darken them.
Does natural light affect my sleep differently than artificial light?
Robert Thomas: It depends on when (time of day) and where (latitude). Nothing quite matches intense tropical light. Light in winter in the extreme north can be limited, so artificial lighting preserves sanity. Wavelength-wise, both white artificial light and sunlight have enough blue light to support circadian functions.
Maya Ramagopal: The body’s circadian rhythm is in line with natural light. This allows us to stay awake during the day and sleep at night. Exposure to artificial light at the ‘wrong’ time can mess up a person’s circadian rhythm. Being out of sync with the day-night schedule can cause a variety of health problems.
Matteo Cesari: Artificial light is different from natural light. The brightness of natural light is far greater than artificial light. Artificial light is available all the time. This creates the potential to confuse the circadian rhythm. Whereas natural light exposure during the day reinforces circadian rhythm, making it easier to sleep at night. Sleeping with any light, natural or artificial, will negatively affect the quality of sleep.
My child feels safer with a nightlight while sleeping, will that affect the quality of their sleep?
Maya Ramagopal: Children in general are more sensitive to light than adults. So, melatonin suppression with light exposure can be more pronounced in children than in adults. Of course, young children can be frightened of the dark, so a night light that is dim (less than 1.5 lux) and gives off a red or orange glow is best.
Robert Thomas: Excessive light while sleeping disrupts the biology of sleep. A dim light, ideally zero lux, at the child’s eyes should be fine. If the light exceeds 30 lux at the child’s eye, that is too much. Less than 10 lux is probably OK. You can measure the light around yourself with apps like Light Meter or Lux Meter, they are not perfect, but they will do.