Light and its Health Effects
Chronobiology, the influence of light exposure on humans in physical, mental, and behavioral ways has recently become a focus of research and discussion. Do light and its exposure affect humans? If so, in what ways? Light plays an important role in the health of humans. It starts with the ways our bodies react to day and night and our associations with that. We make these associations because it changes the levels of melatonin produced within our bodies. Melatonin is a hormone that helps promote sleep and helps us to alert appropriate times of day. Levels of Melatonin are connected to the light taken in through the human eye.
Ganglion, a receptor cell in the human eye, senses slowly changing light patterns. It sends these changes to the nerves which matches brain and body responses to circadian rhythms. This transfer of information affects the body’s endocrine, immune, cardiac, metabolic, behavior responses, and more. Therefore, it is very important our bodies are taking in enough sunlight throughout the day. If we do not get enough natural light, we can develop, SAD. Seasonal Affective Disorder is a disorder where depression occurs due to the lack of light. We can also develop vitamin-D deficiency. This is where we do not receive enough vitamin-D our body needs.
Because of these medical issues related to exposure to natural light, studies have started to see which lights help and which ones hinder us. One of the lights that have found to help is the LED blue wavelength lights. These light bulbs are found to slow down the release of melatonin. This allows one to stay awake longer and be more alert. They have also seen higher memory and cognition through people who have been exposed to blue wavelengths. However, though blue wavelength lights have said to be better, one has to consider the intensity of those lights. If a human is exposed to bright lights followed directly with no light without a transition it is not a natural cycle. Therefore, using a dim light to transition from a bright light to darkness is best. It will not take one as long to fall asleep.
Though blue wavelength lights and dim lights have helped humans in some way, we must also consider the time exposed to light at night in excess can affect a human’s weight. More hours awake and in the light, the more often one will eat and consume. This can create health problems too.
Therefore, it is best to follow the natural rhythms and characteristics of light when designing a lighting environment. Allowing the light to be natural or follow the natural pattern is best for our health. By doing this human health can improve and we can still get the vitamin-D we need and can improve statistics of people with SAD.