If shorter days and colder weather have you feeling the melancholy, it may be the season that’s got you down.

Studies have shown that anywhere from 10 to 20 percent of Americans may get the winter blues, otherwise known as seasonal affective disorder (SAD).

“Symptoms of SAD can appear as the days get shorter and colder in the fall, peak in winter and subside as the days get longer and warmer in the spring,” said Mercy Clinic sleep specialist Adeel Khan, MD. “For others, symptoms may appear just in winter.”

Cases may be mild to severe and symptoms may include:

Increased appetite and weight gain;

Lack of interest in usual activities;

Inability to concentrate or focus;

Loss of energy, fatigue;

Social withdrawal;

Depression; and

Suicidal thoughts or behavior.

Sleep disturbances are also common among people experiencing SAD. They may sleep more than usual and have episodes of insomnia. Sufferers commonly complain they just don’t feel rested.

SAD is a real disorder. Lack of sunlight is its main cause. Darkness affects brain chemistry levels, impeding mood and sleep. But people can take measures to try to restore that balance. Dr. Khan said people should take steps to bring sunlight to them, such as:

Opening curtains and blinds;

At work, taking breaks outside or near windows to soak up sunlight;

Making home improvements to bring more sunlight indoors such as adding windows and skylights and removing obstacles like shrubbery that could be blocking sunlight;

Taking activities outdoors, such as walking, playing, relaxing, reading, eating, visiting with friends — or whatever comes to mind;

Taking vacations to sunny climates.

“In addition to light, exercise is one of the best things we can do to restore mood and sleep cycles,” said Dr. Khan. “Exercise releases chemicals that reduce stress and anxiety and can restore imbalances related to SAD.”

For sleep disturbances, Dr. Khan recommends trying to identify what is making people sleep too much, such as spending too much time in bed, or keeping them up too late, such as too much caffeine, and modifying those behaviors; creating a dark and silent bedroom; and setting a consistent sleeping schedule. Staying active all day and winding down an hour or so before bed also will help.

All of these measures will make notable differences in many cases of SAD. Advanced cases, however, may require advanced care.

“Some patients require medication, light therapy or psychotherapy or a combination of the three to help restore their mood,” said Dr. Khan.

Light therapy uses a special light bulb that mimics sunlight to modify brain chemistry and improve mood changes associated with SAD. Antidepressants will help stabilize mood changes and help with depression during the cold months, too. Light therapy should be supervised by physicians, and antidepressants are prescribed and supervised by physicians.

Dr. Khan is a part of Mercy Clinic Pulmonology and Sleep Medicine Washington, Suite 302, 851 E. Fifth St. in Washington. For more information, people should call 636-239-8832.

For more information about SAD, depression or sleep disorders, people should contact their Mercy Clinic physician or visit www.mercy.net/doctors.

Mercy is the sixth largest Catholic health care system in the United States and serves more than 3 million people annually. Mercy includes 31 hospitals, 300 outpatient facilities, 39,000 co-workers and more than 2,000 integrated physicians in Arkansas, Kansas, Missouri and Oklahoma. Mercy also has outreach ministries in Louisiana, Mississippi and Texas.

Mercy Clinic is a physician-governed group of more than 1,700 medical providers across Arkansas, Kansas, Missouri and Oklahoma.