London Drugs

Focus On Health

Winter - Spring 2010

Spring - Summer 2009

Winter - Spring 2009

Just How Healthy Are You? (Part1)

Silverts Adaptive Fashions

Catching a Cold

The Relaxing Power of Colour

Reducing Workplace Stress

Just How Healthy Are You? (Part 3)

Say Goodbye to Dry Winter Skin

Quit Smoking the Easier Way

When Little Ones Are Sick

Relieving Ear Pressure

Controlling pain

Blood Pressure and Your Heart

Oops what did you just touch?

Measuring Your Personal Metabolism

Don't Worry: Be Healthy

Seasonal Affective Disorder

Just How Healthy Are You? (Part 2)

In This Issue

The Science of Cold Prevention

Supplements for Heart Health

Seasonal Affective Disorder

Seasonal Affective Disorder

Feeling low from time to time is perfectly normal. A late night, too much on one’s plate or an unhappy event can cause temporarily sadness or the“blahs.” When feelings of melancholy are ongoing, however, and coincide with the shorter days of winter, you could be experiencing Seasonal Affective Disorder (SAD).

Seasonal Affective Disorder (SAD) or “winter blues” is a type of depression that researchers believe is caused by an increase in the brain’s daytime output of the sleep hormone, melatonin. Melatonin is secreted by the pineal gland—a small structure at the base of the brain—when the retinas of the eyes detect the absence, or near-absence, of light.

For most adults, melatonin is typically released between 9 and 11 p.m., when we begin to wind down in preparation for sleep. Melatonin levels continue to increase throughout the night, peaking between 3 and 5 a.m. and gradually drop off as morning approaches. People with SAD or winter blues continue to produce melatonin after waking. Scientists believe that the absence of early morning sunlight during the winter months results in the eyes not receiving the cue that nighttime has ended. The body therefore continues to produce melatonin, giving rise to feelings of sluggishness and fatigue, when everything is an effort, and the desire to rest or sleep can be overwhelming. Other symptoms of SAD include the desire to keep eating, particularly sugary and starchy foods, and a general feeling of melancholy and sadness.

Who is most affected?

The symptoms of SAD usually begin in October or November and subside in March or April. Women (particularly younger women in their 20s and 30s), are most likely to experience SAD.

The frequency of SAD and winter blues rises as distance from the equator increases and when daylight hours decline with the onset of winter. In the United States, for example, incidence of SAD and winter blues is ten times more common in the northern states than in the south. Here in Canada, incidence of SAD is high due to our northern location on the planet. Weather patterns may also affect the frequency, with cities that experience prolonged cloud cover and/or rainy climates in fall and winter—such as Vancouver and Halifax— reporting a higher incidence of SAD or winter blues.

What can be done?

Light therapy, also known as phototherapy, is a highly effective way to treat SAD. It is generally believed that light therapy suppresses the daytime release of melatonin, accounting for the increased energy and absence of melancholia reported by light therapy users. A small, portable form of light therapy device, The Litebook® Elite™, emits light that peaks within the exact wavelength shown to be most effective for suppressing melatonin. The device requires only 15 to 20 minutes’ use per day.

A 2007 study reported in the BioMed Central Psychiatry Journal, looked at the effectiveness of a Litebook® LED light therapy device in the treatment of SAD. The randomized, double-blind, placebocontrolled trial followed 23 participants aged 18 to 65. At the end of four weeks, the participants who had received the true LED light therapy emitted by the Litebook® (as opposed to a placebo) showed significantly better ratings in depression scores than those receiving the placebo light. While light therapy is considered safe and effective, it is important that you consult your doctor if you have a history of eye disease, or if you have not yet received a diagnosis of SAD or winter blues.