Extensive research has shown that lack of natural daylight can impair our mood, health and well being in a very dramatic way.
The quality of our daily lives is greatly affected by the type of artificial illumination we use, at home or at work, where we spend a great deal of our days. Unfortunately, ordinary cool white fluorescent lamps, that most of us use (rather than full spectrum lighting found in some lamps and the sun) have an unbalanced spectral distribution and throw a depressing greenish yellowish hue upon a room, distorting colors, stressing our eyes, creating a very unpleasant atmosphere, and may even cause cavities.
The quality of our daily lives is greatly affected by the type of artificial illumination we use, at home or at work, where we spend a great deal of our days. Unfortunately, ordinary cool white fluorescent lamps, that most of us use (rather than full spectrum lighting found in some lamps and the sun) have an unbalanced spectral distribution and throw a depressing greenish yellowish hue upon a room, distorting colors, stressing our eyes, creating a very unpleasant atmosphere, and may even cause cavities.
In recent years, full-spectrum lighting has been used in the treatment of seasonal affective disorder (SAD) through the use of "light boxes" that mimic natural sunlight, which may not be available in some areas during the winter months. But can full spectrum lights actually prevent cavities from forming?
A nine-month long study of first grade children in windowless classrooms found that those under full-spectrum fluorescent lights had many fewer cavities in their newly formed permanent teeth than those under standard "cool white" fluorescent bulbs. It turned out that ten times as many children under cool white bulbs had new cavities. Many fewer cavities were also found when incandescent bulbs, which are higher in red and infrared, were used instead of full-spectrum fluorescent bulbs. The authors also found that a broad spectrum of ultraviolet, red and infrared light was important for the formation of teeth as well as resistance to decay.
Furthermore, the development of the male sexual organs was only one fifth as great in those hamsters under cool white light as compared to those under full spectrum light. Of course, this result correlates with our knowledge that testosterone, a steroid hormone, is dependent on Vitamin D for its synthesis, a vitamin that we make from sunlight.
It has also been found that the role of full-spectrum light benefits the eyes as well as when it strikes the skin. The natural light received by the eyes plays a vital role in body chemistry. The light received by the eyes influences the hypothalamus, which in turn influences the pituitary and pineal glands. The pineal gland especially is involved in our diurnal rhythms, and our lack of quality light through the retina may be the source of many sleep disorders that are increasingly common among people who are always indoors.
Much research on this subject has been summarized by the German ophthalmologist Fritz Hollwich, MD, as well as by John Ott, Hon. D. Sci., a researcher on the properties of light. The array of bodily organs and systems that depend on full-spectrum light through the eyes is astounding. When the eyes are exposed to natural sunlight or full-spectrum light, the pituitary gland, thyroid gland, adrenal glands, ovaries, testes, pancreas, liver and kidneys all function better, according to the numerous studies. Full-spectrum light includes a balance of wavelengths from all colors of the visible spectrum plus ultraviolet and infrared. On the other hand, cool white fluorescent bulbs, which are now used for the great majority of interior commercial lighting, have strong yellow, but are very deficient in most of the other wavelengths, with no ultraviolet or infrared.
Unfortunately, however, UV light has received a bad name, primarily because of individuals who have a history of blistering sunburns followed by skin cancer. There has never been any research showing health benefits of blocking UV light to the eyes. However, it is now impossible to buy eyeglasses that allow full-spectrum light. All of the lenses made in the last ten years for eyeglasses are made to block UV light, even plastic lenses, which if untreated, would allow full-spectrum light. However, full-spectrum light to the eyes is necessary for proper functioning of ovaries, testes and thyroid, according to Hollwich and the research he summarizes.
Earl Staelin, writing in the current issue of the Well Being Journal, summarizes the recommendations of those who have studied light and its health effects, and recommends that individuals who must wear glasses try to get outdoors everyday for 20 to 60 minutes or more without wearing any glasses. If the weather makes this impractical, then it would be beneficial to try to function without glasses indoors under full-spectrum lighting, because the amount of UV light that strikes the retina from around the edges of glasses is insignificant compared to the large amount of light coming through the eye and through the lenses. The full spectrum of daylight need not come from direct sunlight, but is available also on a cloudy day or under the shade of a tree or porch. Glass windows however, do block out UV light, so try to get out in the fresh air if at all possible.
About Full Spectrum Products
"Full-spectrum" is not a technical term when applied to an electrical light bulb but rather a marketing term implying that the product emulates natural light.
Products marketed as "full-spectrum" may produce light throughout the entire spectrum, but actually do not produce an even spectral distribution, and may not even differ substantially from lights not marketed as "full-spectrum".
Color temperature and Color Rendering Index (CRI) are the standards for measuring light. There is no technical definition of "full-spectrum" so it cannot be measured. To compare "full-spectrum" sources requires direct comparison of spectral distributions.
The only real full-spectrum source is the sun. There are some electric light sources that come pretty close (with CRI 90 and color temperature greater than 5000K) but nothing available for commercial use that is truly full-spectrum. A more accurate term would be “fuller-spectrum”.
After research, I found one that seems like a great one: Here You might even be able to buy it at Home Depot for cheaper and minus the shipping.
- Earl Staelin, "The Central Roles of Hormones and Natural Light." Well Being Journal. May/June 2006. p27+.
- Mayron, Ott, Amontree and Nations, "Caries reduction in school children." Applied Radiology. July/August 1975. pp 56-58.
- Sharon, Feller and Burney, "The effects of lights of different spectra on caries incidence in the golden hamster." Archives of Oral Biology. Vol 1, No. 12 1971. pp 1427-1432.
- Fritz Hollwich MD. "The Influence of Ocular Light Perception on Metabolism in Man and Animal." Springer Verlag. New York. 1979.
- John Ott D. Sci Hon. "Health and Light." Devin Adair Co. 1976.
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