If you’re feeling a bit blue as winter sets in, you’re not alone. According to Dan Adams, Research Manager at Apollo Health (now part of Philips Home Healthcare Solutions) 14 per cent of the US population experience the “winter blues” and 6 per cent suffer the more severe symptoms of Seasonal Affective Disorder (SAD).

In years gone by, humans rose and set with the sun, keeping their circadian rhythms in sync with nature. When the light bulb was invented, our sleep problems began as technology interfered with darkness, our natural sleep cue.

Today, Adams and the team at Philips work with leading researchers to better understand how light effects us and to apply new technology to the problem. They’ve made a lot of progress in the last several years.

Our bodies produce different hormones during the day and night, and early studies established that light causes the body to stop producing melatonin. This led to the first light therapy products, which used 10,000 LUX of white light (usually fluorescent) to simulate sunlight. While that’s much brighter than normal indoor residential lighting (typically 50 to 200 LUX), it’s still less intense than what you’ll experience outside on a sunny day (50,000 to 100,000 LUX).

Then, earlier this decade, things got even more interesting.

In 2001, Dr. George Brainard, a neuroscientist, discovered the “action spectrum of light” at at a wavelength of 464 nm and hypothesized that, since 464 nm didn’t correspond with the known response ranges of rods and cones in the eye, there must be a novel photoreceptor that was responsible for circadian regulation.

In 2002, Dr. David Berson at Brown University discovered that this novel photoreceptor was melanopsin. The discovery set off an explosion of interest and studies and, later in 2005 and 2006, several articles were published in Nature and Science, describing the role of melanopsin including how it regulated pupilary constriction and dilation and the circadian response.

Since LEDs can be manufacturer for specific wavelengths, this series of discoveries has lead to the development of smaller, lighter and safer light therapy products. For example, the Philip’s goLITE BLU emits the approximate equivalent of 200 LUX.

The device is 14 cm x 14 cm x 3 cm (5.5 in. x 5.5 in. x 1in.), weighs 400 g (14 oz.) and is rechargeable — all things simply not possible in a 10K LUX lamp.

During my research on the topic, I found Web sites, including that of another manufacturer, claiming blue light is more dangerous to the eyes. Adams explained that any colour of light can be dangerous if the intensity is too high but that, to put it into perspective, the goLITE BLU produces about 5 per cent of the blue light that one would be exposed to by walking outside on a sunny day. According to Adams, the company has performed safety studies on the product and two independent third parties have also confirmed that the product is safe.

For another opinion, I asked my optometrist. He confirmed that the primary concern is exposure to ultra violet (UV) light and that the blue light therapy devices are considered safe (assuming no UV, which is the case with the Philips products.)

The goLITE BLU is used for 15 to 30 minutes per day, at about an arm’s length away off to one side, while eating, reading, etc. Light reaches the melanopsin through peripheral vision and it is neither preferable nor more effective to stare into the light. In essence, the product simulates exposure to sunlight, which can reset your internal clock and also help compensate for the decreased sunlight those of us at higher latitudes experience during the winter.

Philips offers a free online assessment on their Web site. You simply answer a set of questions, and the site determines what is happening to your circadian rhythm and presents recommendations on when and for how long you should use the product. And, if you’re a business traveler, they also have a neat tool to help you beat jetlag.

The Philips Home Healthcare Solutions product portfolio also includes another interesting product, the Daybreak Duo: A clock radio that controls your bedside lamp to simulate dawn and dusk.

According to their Web site, “The Daybreak Duo creates a natural sunrise that tells your body clock that it’s time to wake up, gently waking your body from its final sleep stage so you can wake refreshed and alert.”

The theory behind this, Adams explained, is that our body recognizes even a small amount of light as dawn, and it triggers us to stop producing melatonin.

Philips was kind enough to send me both a Daybreak Duo and a goLITE BLU to test. Keep your eye on techlifepost.com for upcoming full reviews!

As for the future, it does appear that circadian regulation effects all of the body’s major systems and that light plays a critical role in our internal body clock. To quote Dan Adams, “This science is young but we’ve made great strides and I think you’ll see even more amazing revelations in the future.”