Light Treatment for Seasonal Depression

Seasonal affective disorder is a mood condition caused by a decrease in brightness and intensity of natural sunlight during the fall and winter. The condition is characterized by a lack of energy, oversleeping, an abnormal craving for foods rich in carbohydrates and sugars, and feelings of sadness, guilt or anxiety. Several million Americans report suffering from a mood shift during the winter, but according to research by M. Said of the University of Liverpool in the U.K., this is significantly fewer than the number of actual cases. While there are several treatments for individuals suffering from SAD, including antidepressants and talk therapy, one of the most successful treatments is light therapy.

Effects

• Light therapy, also known as phototherapy, utilizes a full-spectrum light bulb to simulate bright, natural sunlight. According to research by the Mayo Clinic, SAD is caused primarily by an overproduction of the brain chemical melatonin. Melatonin is produced when the pineal gland processes the amino acid tryptophan. It is known to cause drowsiness, sugar cravings and sluggishness. The production of melatonin is triggered by darkness and the absence of natural light and is noticeably increased during darker months. Light therapy works by exposing the brain to intense, synthetic sunlight, repressing the production of melatonin and decreasing symptoms.

Use

• Individuals managing SAD with light therapy are instructed to sit in front of a full-spectrum light, referred to as a light box, for about 30 minutes every day. It is best to use the light box first thing in the morning after waking to nip any melatonin production in the bud. It is also suggested that individuals use the light box at the same time every day to keep their sleep rhythms consistent and help regulate melatonin levels throughout the day.

Considerations

• Results of light therapy--decreased or eliminated SAD symptoms--tend to manifest after two weeks of consistent light-box use. For these benefits to occur, it is vital that the box be used every day. Many patients using light therapy will stop or become less disciplined with treatment as their symptoms decrease and they feel better, but if usage is decreased or stopped, SAD symptoms will return in seven to 12 days. To maintain success, light therapy must be used daily during low-light months.

Cost

• Light boxes are a home treatment and may be purchased through medical stores or online. Their cost range from $90 to $200, depending on their size and manufacturer. Available models include sizes ranging from desk lamps to freestanding floor lamps, but the size is for convenience and preference and does not have a bearing on the light's effectiveness. The only key aspect to look for when purchasing a light box is that the bulb is full spectrum.

Warning

• While light therapy is extremely successful in treating winter SAD, it is ill-suited for the less-common summer variety. Summer SAD is characterized by an increase in energy, irritability, lack of sleep and reduced need for food. While emotional lowness, such as feelings of sadness, guilt or anxiety, are also associated with summer SAD, light therapy actually provokes and intensifies symptoms instead of curbs them.