How can white light therapy help you get through the winter blues?

Melatonin production increases as light intensity falls and it is responsible for inducing sleep. Alertness, vigilance and mood are all directly related to the levels of melatonin in the circulation. Melatonin production is suppressed by early morning sunlight and this action resets the body clock on a daily basis. Melatonin is produced from the feel-good hormone serotonin. If there is no suppression of melatonin we experience the combined effect of high melatonin and low serotonin with symptoms including depressed mood, lethargy, lack of energy, poor sleep patterns, loss of libido and carbohydrate craving. In summary, low exposure to sunlight causes elevated melatonin levels and low serotonin levels.

The reverse is true when we are exposed to plenty of sunlight. We all know how much better we feel when the sun is shining. SAD Light therapy first became an option for the treatment of seasonal onset depression (SAD) following the discovery in 1971 that very bright light could influence the control of the hormone melatonin. 40% of the population suffers from SAD, usually defined as winter blues. There is growing evidence that the lack of bright morning light can also cause non-seasonal depression with all the attendant symptoms. Light deprivation symptoms are also experienced by those who live in conflict with their body clock such as night workers, shift workers and international travellers (jet lag).

For physiological reasons the body clock is also shifted at two key life stages. It moves forward by 4 – 6 hours at puberty meaning that teenagers and students do not feel sleepy until the early hours and cannot wake before noon, Later on in life the body clock shifts back leading to poor sleep patterns and a tendency to wake in the very early hours. Research in the last few years has also confirmed that melatonin suppression is under the control of very specific wavelengths of light. 460-470nm at the non-visible blue end of the spectrum activates melatonin and green light at 540nm resets the receptor. Bright sunlight peaks at 470nm with a second smaller peak at 540nm suggesting that the primeval development of the process was very much determined by environmental factors.

If you want to wake up quickly, in a good mood with a smile on your face, then you need to reduce your melatonin levels and boost your Serotonin levels and the Litebook is one very easy way to do this.