Light on Human Health and Welfare Paper

Shirley Bircher

Light on Human Health and Welfare

The impact of light on human health and welfare is immense.  Not only does light affect your mood, but it can also have an effect on one’s health.  Human’s bodies have evolved to recognize daylight rhythms, whereas our systems have not yet adapted to electrical lighting.
            Day light offers an amount of melatonin, and from these changing levels of melatonin one is naturally able to transition from wakefulness to sleepiness at night.  The retina detects this rise and fall of daylight and evolutionary programming does not agree with one’s eyes being filled with electrical lighting after night has already fallen.  It is said to disrupt the circadian rhythm.
           Circadian rhythms focus on cardiac responses rather than melatonin studies.  Through this ongoing study it is determined that one’s body responds to a large range of light spectra.  Designers should take this into consideration and reduce circadian disruption.  There are several ways in which they can do this, such as site planning, shading and screening systems, electrical lighting systems, building orientation, and architectural openings. 
            Unfortunately there are several harmful effects of attaining the wrong amount of light.  For example, a person who works night shifts has an increased cancer risk.  Receiving too much light at night has been proven to cause breast cancer and even weight gain.  Most commonly though, lack of light can lead to Seasonal Affective Disorder (S.A.D). S.A.D happens when a person receives an inadequate amount of lighting for a prolonged amount of time.  Not only are they lacking Vitamin D, but also their circadian rhythm has been disrupted. This is why in some parts of the world people are more likely to be depressed in the winter than the other seasons.  Ultimately, light has a major power over humans in that it not only can control our feelings, but it can even control our health.