Light Therapy: Shine Away the Winter Blues

It's the time of year when the days are shortest and the cold temperatures keep us mostly indoors. This lack of sunlight can make anyone feel a little blue. Daily exposure to sunlight is very important, says Dr. Andrew Weil, who is a world-renowned pioneer in the field of Integrative Medicine and director of the Arizona Center for Integrative Medicine.

To some, this case of "winter blues" is severe enough to be diagnosed as Seasonal Affective Disorder (SAD). It usually begins in late fall and early winter and goes away during summer. SAD is more common in northern states.

Approximately 10 percent of Americans suffer from mild SAD. It is more common in women and typically doesn't start in people younger than 20. Some symptoms of SAD include:   

• Change in appetite, especially a craving for sweets              
• Weight gain
• Heavy feeling in arms or legs
• Decreased energy
• Fatigue
• Too much sleep
• Difficulty concentrating                
• Irritability            
• Avoidance of social situations

Light therapy is one way to treat this severe type of winter depression. Light therapy (also known as phototherapy or bright light therapy) uses light boxes that emit full-spectrum light similar in composition to sunlight. The light boxes used for light therapy are designed to filter out ultraviolet light and therefore aren't dangerous like tanning beds.

Daily exposure to this bright light is the treatment most recommended for patients with SAD. This therapy is effective in the majority of SAD cases. Proponents of light therapy say it works by stimulating compounds in the central nervous system that regulate mood, although sometimes it takes up to two weeks to feel the effects. When used properly, light therapy has very few side effects. For some people, eye strain and headaches have been reported.

The treatments consist of 30 minutes of light therapy every day from early fall until spring. After that, outdoor light becomes strong enough to boost mood naturally. For best results you should sit in front of the light right after waking in the morning, making sure to sit in front of the light with eyes open but not looking directly at the light. It is fine to read, write or eat while in front of the light.

Light therapy has been used to treat other types of depression, to boost the effects of certain antidepressants, to lower the dosage of antidepressants for some patients, and as a substitute for some antidepressants during pregnancy and breast feeding. It has also been used in the treatment of insomnia and bulimia. Studies are currently underway to test if light therapy could be an effective treatment for obsessive-compulsive disorder, PMS, jet lag, Parkinson's disease, dementia, and ADHD.