Light

Examinations of hormone levels in blind persons compared with almost blind and people with normal vision and hormone evaluation with increased artificial light exposure show a definite stimulating effect of light on the human hormonal balance. The effect of light is mediated by an intact perception of light by the eye over an "energetic part" of the visual pathway (Hollwich 1948) - hypothalamus - hypophysis - peripheral endocrine gland. Increasing the intensity of artificial light with "neon-tubes" (fluorescent tubes) leads to "light stress" proved by increased hormone production - especially the stress hormone Cortisol. Under equal conditions, the full- spectrum fluorescent tubes produced significantly less of the "stress hormones" ACTH and cortisol, than were found with the widely used standard cool-white lamps.

"In other words, from the standpoint of health, this broad spectrum tube is much better tolerated regarding the endocrine response of the human body than the standard cool-white one."

(Page 94 of Hollwich's book, "The Influence of Ocular Light Perception on Metabolism in Man and in Animal")

To high levels of the hormone cortisol or by the overproduction of cortisol in the body include:

Ø upper body obesity

Ø severe fatigue and muscle weakness

Ø high blood pressure

Ø backache

Ø elevated blood sugar

Ø easy bruising

Ø bluish-red stretch marks on the skin

Ø In women, there may be increased growth of facial and body hair

Ø menstrual periods may become irregular or stop completely

The stress hormone cortisol causes a rise in blood pressure.

High blood pressure, or hypertension, together with its associated complications, is a common cause of death in industrialised nations. It is estimated that up to 50 million Americans have high blood pressure, and many cases of hypertension may go unrecognised.

THE FACTS YOU SHOULD KNOW:

THE FEDERAL GOVERNMENT OF GERMANY

has imposed a complete ban on the use of cool-white fluorescent tubes. This on the basis that their continued use was seen as harmful to the state of the nations health, particularly the workforce. Therefore today in Germany on a Federal level it is illegal to install cool-white fluorescent tubes.

The belief that artificial light is the same as natural light and that it can fully replace it, is inappropriate in the medical view and needs correction.

STRESS IN THE WORKPLACE

It is no secret that since the majority of Americans spend over half their lives at work, the thought of the office does not evoke the most positive images for most of us. What most people do not realize, however, is that it may be the office building itself that is causing the feelings of stress and fatigue experienced by most working people.

For at least eight hours a day each week, most of us work under lights we would never consider putting in our homes. Headaches, eyestrain, and foggy thinking - symptoms most commonly attributed to stress or fatigue are actually the result of the antiquated fluorescent lighting still being used in 99% of offices nearly 75 years after its invention, despite overwhelming scientific evidence that it is harmful to people’s health. A recent Steelcase Workplace Survey illustrated the need for change with over half of the workers surveyed stating that poor lighting in the workplace triggers tired or watery eyes, and another third of office workers stating they suffer headaches from poor lighting.

A related study found that more than 10% of workers complained of sore eyes every day. More than 50% suffered sore eyes at least once a week. (OHM issue No. 93)

Recent reports conclude, "The results support the conclusion that artificial lighting simulating natural light (full spectrum lamps) is perceived as significantly more pleasant, natural, bright and stimulating. Subjects felt more relaxed, less fatigued and as having greater eye comfort under the simulated natural light Additionally, they rated their work as being more distinct, easier and satisfying. " (Hughes. 1986)

It has been found that full-spectrum lighting in the work place creates significantly lower stress on the nervous system than standard cool-white fluorescent lighting and reduces the number of absences due to illness. These findings seem to indicate that full-spectrum lighting may act to boost the immune system in the same way as natural sunlight. Excerpt from "Light Medicine of the Future," by Jacob Liberman, O.D., Ph.D.

Our eyes evolved in full spectrum light. It is the light in which we see best. Standard cool white fluorescent light does not provide the type of light conducive for high color rendering. Lack of good color rendering is one reason people view objects next to windows to see colors and textures more clearly, although the light level in the room may seem adequate.

The advantages of full spectrum light in the indoor environment include:

Ø perceiving fine details clearer;

Ø performing visually demanding tasks (such as color matching) more effectively;

Ø reducing glare, thereby

Ø lessening eye fatigue and strain; and

Ø reducing maintenance and replacement cost due to its long life features.