Sleep Hygiene
Sleep is the main natural restorative process for the human mind and body, and light exposure has been proven to be a main contributor to improve and/or disrupt sleep. Since the advent of electric light, that facilitates human 24/7 activities, sleep disorders have become a major concern in today’s urban lifestyle and society.
According to the US National Sleep Foundation, sixty five percent (65%) of Americans report experiencing a sleep problem. Besides issues directly associated with bad mood and lower performance at work, or at school/academia, poor sleep has also a major drawback in our social and family interactions, and drowsy driving constitutes a high risk in the road. Chronic sleep debt can also lead to poor health conditions such as hormonal imbalance, weight gain, diabetes and cardiovascular disease occurrence.
And, guess what: obesity, diabetes, cancer and cardiovascular disease are main leading causes of death in the USA. So, how can adequate light exposure improve our sleep? Light exposure means not only light, but also the need of darkness, a key element for health that has been lost in modern societies.
The circadian rhythmicity, light/dark cycle, of our nature demands high levels of light during the day, particularly in the morning, and lower levels of light before going to sleep. In terms of spectrum, wavelengths, our body requires the presence of short wavelength emissions, blue around 480nm, to wake up properly in the morning and blue depleted light before going to sleep.
Proper sleep requires total darkness so that melatonin is properly produced to induce sleep. Finally, keep in mind that sleep begins sixteen hours before starting to sleep, sleep is the consequence of a whole day process, and this means a whole day of light exposure.