Impact of Light on Health and Welfare
F.D.
University of North Carolina – Greensboro
Course: Materials, Methods, and Techniques IAR 333-01
Instructor: Tina Sarawgi
Date: August 30, 2009
Impact of Light on Health and Welfare
Human health and welfare is greatly affected by natural and electric light. In what ways has natural and electric light impacted human health and psyche? Whether light promotes or disables good physical and mental health is based on the quality of the light and how/when it is used for interior and exterior lighting. Current and future studies linked to lighting and healthcare are bound to reflect the way in which interiors are designed in the health industry and in residential dwellings.
The quality of natural light can create beneficial and damaging affects on our health and psyche. Natural light can be glaring, diffused, reflective, harsh, dim, and luminescent, etc. These descriptions of light can be controlled to reduce its bad affects (Edelstein, 2009). Harsh direct sunlight can contribute to someone feeling hotter in an air-controlled room. By diffusing natural light, the light can still be bright, but not harsh. Thus, light can be evenly dispersed to simulate natural light in an open field, on a cloudy day. Usually, it feels cooler when it is cloudy out, and hot under the direct sunlight. By controlling the intensity of the natural light we can create a more comfortable interior atmosphere (Edelstein, 2009). This can be put into even a broader topic of how the reflective qualities of finish materials and products, such as blinds or curtain determine how natural light enters and exists in a room.
The quality of electric light can also create positive and negative affects on our physical and psychological health. If a person lets natural light into their home during daylight hours, they will generally use electric light in the rooms not well lit by the sun. So when are bulbs that are energy-efficient necessary? It seems that these would be best used in a room that is not well lit, while coinciding with daylight hours. If a bulb such as an energy-efficient fluorescent were used, it would inhibit a person’s melatonin production (Weiss, 2008). Based upon the 2009
article by Edelstein and the fact that fluorescents give off a blue light, this type of light creates a wakefulness response. One can concluded, that if used at night, this same light would pose a problem by restricting the production of melatonin. The problem is our bodies aim to produce more melatonin during the nighttime (Weiss, 2008). Such a situation, disrupts our internal circadian rhythm, “biological cycle” (Steffy, 2008). Our bodies are not naturally meant to feel alert when we are mentally aware it is nighttime outside. The receptor cell, ganglion, signals “light changes to nerves to synchronize the brain’s and body’s response to circadian rhythms” (Edelstein, 2009). This process “provides cues that can in turn affect the body’s endocrine, immune, cardiac, metabolic, emotional, cognitive, and behavioral responses” (Edelstein, 2009). Thus, if we align darkness hours with electric light, we are disrupting all of the body’s cycles that circadian rhythm plays a role in.
In a healthcare facility, how and when people are exposed to natural light in, can impact the recovery of a patient (Edelstein, 2009). Doctors will always tell you that when you are sick, rest is important. Use of darkened conditions will promote rest and sleep, at anytime of day. (Edelstein, 2009). As we have stated before, the body has a circadian rhythm, so once a patient is in remission they may receive more exposure to natural. In turn, this should help adjust the patient’s body to its typical association of light and time. One could conclude, that over exposure to darkness could create illness in healthy bodies. For instances, being under exposed to natural light can cause physical and psychological aliments (Steffy, 2008). Seasonal effective disorder, SAD, “is a seasonal disorder attributed to” the limited time exposed to and/or intensity of natural light (Steffy, 2008).
A friend of mine recently told me of how depressed her sister was and how her home was always kept in darkness, with the blinds and curtains closed. Her sibling has created an
environment of darkness, which countries like Iceland have because of the length of its seasons. When comparing both cases to the Weiss 2008 article, you could infer that melatonin levels for both would be high. Ultimately, this creates a change in the body’s circadian rhythm. In the 2009 Edelstein article, she mentions darkness as a condition supporting rest. Therefore in both of the cases listed above, the body would want to be in rest for these long periods of darkness. Have you ever still felt tired after consistently over sleeping. Well over resting and lack of sleep can be harmful. The body isn’t maintaining its natural circadian rhythm if you’re sleeping into daytime, while driving on lack of sleep is dangerous. In order to maintain a healthy balance in societies that have long dark seasons, light therapy can be successful (Steffy 2008). Exposure to even electric light like fluorescents, which omit a blue light, can help in the recovery of SAD (Steffy, 2008)
How and when electric light is used can be negative and positive. Electric like create positive results in the workforce. Emergency rooms are always well lit with fluorescent electric light. As Edelstein mentioned in her 2009 article, adequate levels of electric light, blue light, aid in stimulating an alert response. At anytime of day or night, this would defiantly be a place employees would need to be fully awake and aware. The negative side to this is based on the 2008 article by Weiss. It sates the study of the negative physical affects that are linked to great amounts of electric light at nighttime. The study was on satellite images, which suggest the nighttime illumination of Earth links electric light to breast cancer (Weiss, 2008). The more excessive the nighttime illumination, the more susceptible the women were to breast cancer (Weiss, 2008). In turn, creating this illusion of natural light during nighttime hours is damaging the body’s natural cycle of maintaining its health. This deception disturbs our circadian rhythm.
The future of designing around how lighting affect health and welfare is vast. As more and more studies become available about how light impacts humans positively and negatively, there can only be a push for creating the positive. The quality of light and how/when it is used will need to become a priority of designers, since it will be one for the public. The focus will not only be on new construction, but also in revamping existing structures. We as designers are not only looked to for innovation, but also for problem solving. Once the general public takes notice of the positive and negative links and prioritizes them, we will be the designers they turn to. The need will expand beyond healthcare facilities and into residential dwellings.
References
Edelstein, E. (2009). Influence of Architectural Lighting on Health. InformeDesign Newsletter, 7 (2), 1-5.
Steffy, G. (2008). Architectural Lighting Design. New Jersey: John Wiley & Sons, Inc.
Weiss, R. (2008). Lights at Night Are Linked to Breast Cancer. Washington Post. February 20
Lighting, Health, and Welfare
