What to know about Seasonal Affective Disorder during the winter months

"SAD is characterized by depression that can begin with sleeping more, feeling exhaustion, and a lack of motivation," Deborah Humphrey, executive director of the Madison County Mental Health Board wrote in an email. "There might be a change in not wanting to do those normal daily activities like caring for yourself, family or going to work or school. Untreated depression also causes individuals to socially isolate themselves."

SAD is not considered a separate disorder but is a type of depression characterized by its recurrent seasonal pattern, with symptoms lasting about four to five months per year. Not every person experiences the same symptoms, the National Institute of Mental Health wrote, although signs and symptoms of SAD include those associated with major depression with some specific symptoms that differ for winter-pattern and summer-pattern SAD. 

Millions of Americans may suffer from SAD, NIMH wrote, although many may be undiagnosed. SAD occurs much more frequently in women than in men and is more common in those living farther north with shorter daylight hours during winter months. In most cases, SAD begins in young adulthood. 

"The Christmas holiday season when everyone else is experiencing happiness, joy, and peace during the holiday season can also further depression when your mood doesn’t match the emotions that others are experiencing," Humphrey wrote. "New Year’s Day is also approaching which for some is the most depressing day of the year. While many celebrate their past years achievements, others reflect on their failures, unmet goals or lack of accomplishments."

SAD is more common in people with major depressive disorder or bipolar disorder, especially bipolar II disorder, which is associated with recurrent depressive and hypomanic episodes. Additionally, people with SAD tend to have other mental disorders, such as attention-deficit/hyperactivity disorder, an eating disorder, an anxiety disorder, or panic disorder. 

SAD sometimes runs in families, being more common in people who have relatives with other mental illnesses, such as major depression or schizophrenia.

Treatment for SAD may include light therapy (phototherapy), medications and psychotherapy.

Symptoms of SAD include: 

Feeling depressed most of the day, nearly every dayLosing interest in activities you once enjoyedExperiencing changes in appetite or weightHaving problems with sleepFeeling sluggish or agitatedHaving low energyFeeling hopeless, worthless or guiltyHaving difficulty concentratingHaving frequent thoughts of death or suicide

Winter-pattern SAD may also involve specific symptoms including: 

Oversleeping (hypersomnia)Overeating, particularly with a craving for carbohydratesWeight gainSocial withdrawal (feeling like "hibernating")

Scientists still do not fully understand what causes SAD, NIMH wrote. Research indicates that people with SAD may have reduced activity of the brain chemical serotonin, which helps regulate mood. In people suffering from SAD, regulation of sunlight, which helps control the levels of molecules that help maintain normal serotonin levels, resulting in decreased serotonin levels during the winter.

Other studies suggest people with SAD produce too much melatonin, a hormone which maintains the normal sleep-wake cycle. Overproduction of melatonin can increase sleepiness. 

Both serotonin and melatonin help maintain the body’s daily rhythm that is tied to the seasonal night-day cycle. In people with SAD, the changes in serotonin and melatonin levels disrupt the normal daily rhythms. As a result, they can no longer adjust to the seasonal changes in day length leading to sleep, mood and behavior changes.

"During the winter season, there is less sunlight," Humphrey wrote. "Studies have found that reduced light during the winter months can affect mood and bring about depression." 

Deficits in vitamin D may exacerbate these problems because vitamin D is believed to promote serotonin activity. In addition to vitamin D consumed with diet, the body produces vitamin D when exposed to sunlight on the skin. With less daylight in the winter, people with SAD may have lower vitamin D levels, which may further hinder serotonin activity.

Negative thoughts and feelings about the winter and its associated limitations and stresses are common among people with SAD (as well as others). It is unclear whether these are "causes" or "effects" of the mood disorder, but they can be a useful focus of treatment.

"If you are experiencing seasonal depression there are things you can do to help combat your depression," Humphrey wrote. "If depression is immobilizing you, Seasonal Affective Disorder Therapy and other depression treatment can help when you feel crippled by intense sadness, hopelessness and emotional numbness."

Other tips Humphrey had for those who may be suffering with SAD include: 

1.    Get out of the house. Go outdoors. Take a walk, walking helps with relaxation when you are overwhelmed and getting sunlight can help with SAD. There is also light therapy when there is limited exposure to sunlight.2.    If money allows, take a vacation somewhere warm.3.    Eat a balanced diet with foods high in vitamin D or take vitamin D supplements 4.    Spend time with a close friend or small circle of friends.5.    Volunteer to help with a children's gift drive, serving food at Christmas dinner for homeless people6.    Join a virtual peer support group or call the IL Warm Line, "Hope Is Just A Phone Call Away"7.    Talk with a counselor8.    If depression worsens to thoughts of suicide, call for help to the National Crisis Helpline (1-800-273-8255)