Control Blue Light for Better Sleep

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Author: Katherine Duff
Date: Nov. 2011
From: Townsend Letter(Issue 340)
Publisher: The Townsend Letter Group
Document Type: Book review
Length: 721 words

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Great Sleep! Reduced Cancer!: A Scientific Approach to Great Sleep and Reduced Cancer Risk, by Richard Hansler, PhD [c]2008; $539; 86 pp.

In the book Great Sleep! Reduced Cancer!, Richard Hansler, PhD, writes that melatonin and its proper regulation can not only give us better sleep but reduce cancer as well. Supplementing with melatonin is not what this book is about; rather, it concerns the efforts that we should undertake to correct the effects of modern living, specifically the use of artificial light.

Melatonin is the main hormone produced by the pineal gland, and it is an important one for the proper functioning of the body. The internal circadian clock directs its production, which in turn regulates our wake and sleep cycles. Melatonin is also a powerful cancer fighter, since it interferes with linoleic acid, which is necessary for tumor growth.

The key to melatonin regulation is light entering the eyes. If a person is in darkness or dim light, the melatonin begins to flow and sleep is possible. If a person is exposed to light constantly, eventually the melatonin production is suppressed, leading to difficulties with getting to and staying asleep. Artificial light then can create havoc in this process, to the extremes that we experience in jet lag or working a job with changing shifts. The kind of light that we are exposed to plays a significant role as well.

The author reminds us that artificial light, other than fire, has been with us for only about TOO years. The artificial light that we are exposed to now has more blue wavelengths, which research has shown suppress melatonin more than those of other colors. To counter this effect, the author recommends using glasses (not sunglasses) that block the blue wavelengths for an hour or two before going to bed. This is not to say that bright light is bad for us. The melatonin production also depends upon exposure to bright light at various times during the day and early evening to keep the sleep/wake cycle synchronized.

Besides insomnia, Hansler has identified several conditions that respond to controlling light. They are seasonally affective disorder (SAD), attention deficit/ hyperactivity disorder, fibromyalgia/chronic fatigue syndrome, bipolar disorder, and postpartum depression. The author includes a discussion of these conditions, and the research that has been done showing improvements after blocking blue wavelengths at critical times. He also provides practical instructions for people attempting to change their sleep schedules and avoid jet lag.

Manipulating melatonin production by reducing blue light for better sleep is not always an instantaneous process, as we learn in the book. It takes time to adjust it and effort to maintain it. For this reason, shift workers are advised to keep the same schedule on their days off. People who want to avoid jet lag should start their preparations four days before their travel day. Those suffering insomnia, though, did remark that results were noted soon.

The discussion of cancer in the book relies upon numerous animal studies that point to the role which melatonin plays in suppressing cancer. Tumors were found to grow in long periods of light and stop or slow growth in long periods of dark.

Hansler came to this subject from his work developing light emitting diodes (LEDs). His interest in light and human health was piqued when he was approached by a friend who wanted him to design an LED blue light for the treatment of SAD. Now, after a career spent improving lightbulbs, Hansler is on a mission to alert people to the safer use of artificial light.

This is a short book at 86 pages, so the information is to the point. By coincidence, while reviewing this book, the popular media carried a story wherein researchers found blue light to be helpful for those suffering from SAD. Based upon the limited information in the articles, sufferers of SAD may bombard themselves with excess blue light and find themselves in an even worse state. They need a more complete understanding of the circadian rhythm, melatonin production, and the role of light to achieve better results. That is what this book offers.

"The main difference between our current artificial lighting and the light under which we evolved is the greater amount of blue wavelength light in artificial light. Blue light is known to suppress melatonin production."

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Gale Document Number: GALE|A271811636