Full Spectrum Light Outshines Others in Classroom

Tuesday, November 24th, 2009

“Striking new evidence suggests that children’s development may be powerfully influenced by a factor their parents rarely consider.
“Academic achievement and physical development may both be dramatically affected by the type of lighting used in schoolrooms, Canadian psychologist Warren Hathaway reported at the annual meeting of the American Psychological Assn. in Toronto. Confirming and extending earlier research, Hathaway concluded that full-spectrum lighting fosters swifter learning, better health and stronger growth than two other commonly used types of light.
“For two years, Hathaway tracked 327 10-to-12-year-olds at schools employing energy-efficient yellow sodium vapor lamps, full-spectrum fluorescent lighting with ultraviolet light inhibited or enhanced, or traditional ‘cool-white’ fluorescent light. Students in schools featuring full-spectrum lighting (with or without UV enhancement) made faster academic progress, were sick less often and recorded greater gains in height and weight than those exposed to sodium or cool-white light. When UV-enhanced, full-spectrum light also reduced dental cavities.
“Full-spectrum lighting was unquestionably best in all regards,” Hathaway said. “Ordinary white light was about neutral, and sodium light had quite negative effects. We’re not sure why, but something important seems to be going on.”
“The results fortify previous findings by Hathaway and other investigators.
“In 1988 Vermont psychiatrist Wayne London reported that the installation of full-spectrum fluorescent lighting in three classrooms reduced sick days by a third. (See Brain/Mind, April 1988.)
Another investigator, John Ott, found that full-spectrum light helped to calm hyperactive students. Shortages of ultraviolet light have long been implicated in SAD, the “winter depression” prevalent in northern latitudes.
“These patterns have been cropping up here, there and everywhere,” Hathaway said. “We think it may be the blue component of full-spectrum light that makes the difference, but we’re not yet sure. Light’s non-visual effects are just starting to be appreciated.”
Before all sodium lamps are replaced, scientists need to determine the optimal ultraviolet balance for full-spectrum light.
“We must find the right dosage,” Hathaway said. “Parents tend to be alarmed at the thought of their children soaking up UV light, but we also know that ultraviolet light spurs the production of vitamin D in the skin. This probably helps the body absorb calcium and keeps cavities down.”
Hathaway said the investigation could also be extended to the effects of different lighting in offices, hospitals and other environments.

Brain/Mind Bulletin of Breakthroughs, Sept. 1993, p. 6.