The concept of light and darkness as opposing forces of nature has been infused in human text since our earliest beginnings. The Bible's divine proclamation of "Let there be light" is one example that comes immediately to mind. Such imagery is often utilized in literature to contrast good and evil, knowledge and ignorance, love and hate or happiness and despair. Medical science might soon start to call upon such literary reference points as the role of light and darkness as its relation to human health takes on new meaning.
A recent example of this is found in a small study conducted by the Laboratory for Sleep & Consciousness Research at the University of Salzburg in Austria. It was found that shining bright lights on patients could have served to help some to awaken from a coma. In this study, scientists discovered they could induce increased levels of consciousness in comatose patients after a treatment with carefully timed bright lights. This therapy was intended to trigger circadian rhythm activity and natural daily body-temperature fluctuations. Circadian rhythms are found in most living things. These rhythms represent physical, mental and behavioral changes that follow a roughly 24-hour cycle that tell the body when to eat, sleep or wake. They are calibrated primarily by light and darkness in an organism's environment and essentially keep a person's internal clock aligned with the environment.
While the findings (published in the journal Neurology) are considered very preliminary, it is hoped that they may one day serve as a diagnostic tool to monitor a comatose patient's chance for recovery.
"We indeed hope we can encourage the cycle to return," said study leader Christine Blume. "We therefore encourage doctors to create an environment in the hospital that mimics the natural cycle of light during the day and darkness during the night."
I talked last week of how the right balance of sunlight during the day can have many mood-lifting benefits. This boost is believed to occur through the release of a hormone called serotonin. Serotonin is associated with enhancing mood and helping a person feel calm and focused. At night, darker lighting cues trigger the brain to produce another hormone called melatonin. Melatonin, as many of you may know, is responsible for helping a person feel sleepy and to fall asleep. When these two hormones fall out of balance, problems occur.
Without enough sunlight exposure, a person's serotonin levels can plunge. Low levels of serotonin, for example, are associated with a higher risk of what is known as seasonal affective disorder, a form of depression that is triggered by changing seasons. One treatment for SAD is light therapy, also known as phototherapy. According to the Journal of Psychiatry & Neuroscience, it's been found that exposure to sunlight can also benefit those suffering from other forms of depression as well as many anxiety-related disorders.
But not all light is created equal and we know that too much light can create health problems. And overexposure to natural sunlight is but one of them. Since the invention of the first practical incandescent light bulb in 1879, and the advent of artificial lighting, evenings tend to be are illuminated in populated areas. We may be paying a price for all that nighttime light.
We are now learning that blue wavelengths, which are beneficial during daylight hours, seem to be the most disruptive at night. Virtually every electronic device we now own — as well as today's energy-efficient lighting — increases our exposure to blue wavelengths. This is especially true after sundown. It can throw your circadian rhythm out of whack. Your sleep can suffer — or worse. Researchers have linked short sleep to increased risk for depression, as well as things like diabetes and cardiovascular problems.
It has also been said that the current trend of switching from traditional streetlamps to LED lighting can be akin to going from a subtropical sunset to high noon at the equator. Today's blue-rich outdoor LED lighting is estimated to have an impact on the circadian rhythms associated with sleep that is five times greater than that of conventional streetlamps. The harsh glare of blue-rich LEDs is thought to not only be a major culprit in disrupting people's sleep patterns, but has been shown to harm nocturnal animals.
It has been only in the past decade or so that experts have become aware of the threat this form of lighting poses to wildlife, to human health, and to quality of life.
LED lights are popular because they are about five times as efficient as traditional incandescent lighting. They are up to 10 percent more efficient than compact fluorescents and said to last anywhere from 2-to-50 times as long as competing products. It's estimated that, to date, municipalities across the United States have installed more than 5.7 million outdoor LED street and area lights in public spaces.
The current challenge with LEDs, as with other energy-saving technology, is to improve energy efficiency without creating further health issues for humans and nonhumans alike. In this case, by messing with our internal clock's alignment with our environment.
Write to Chuck Norris ([email protected]) with your questions about health and fitness. Follow Chuck Norris through his official social media sites, on Twitter @chucknorris and Facebook's "Official Chuck Norris Page." He blogs at http://chucknorrisnews.blogspot.com. To find out more about Chuck Norris and read features by other Creators Syndicate writers and cartoonists, visit the Creators Syndicate Web page at www.creators.com.