A woman stands near a snow-covered tree. While the winter months can be beautiful, they sometimes can e seasonal affective disorder, a type of depression that’s related to seasonal changes in light. SAD can make you feel tired, crave carbohydrates, gain weight, avoid things you normally enjoy or withdraw socially during the fall and winter months. (PxHere stock photo)

HOUGHTON — Does your mood seem to mirror the seasons–maybe growing darker as the fall and winter days get shorter and lifting as the brighter days of summer approach?

You could have a condition known as seasonal affective disorder — a type of depression that’s related to seasonal changes in light. SAD can make you feel tired, crave carbohydrates, gain weight, avoid things you normally enjoy or withdraw socially during the fall and winter months.

“Sunlight helps regulate your internal biological clock. When there are changes in the amount of light you get, that clock gets out of balance, and levels of melatonin — a sleep-related hormon — can increase,” said Jason Bombard, DO, psychiatrist at Aspirus. “This hormone may cause symptoms of depression and disruptions in normal sleep-wake cycles.”

“Additionally, the lack of sunlight causes significant decreases in Vitamin D. This vitamin is activated by sunlight on the skin and can play a role in SAD. Chronic low levels can lead to many other health concerns as well including osteoporosis. Except during the summer months, the skin makes little if any vitamin D from the sun at northern latitudes. People who live in these areas are at relatively greater risk for vitamin D deficiency.”

Not only an adult condition

Both children and adults can get SAD. However, it usually develops between the ages of 18 and 30. Four out of five people affected by SAD are women. Some evidence suggests that the farther you live from the equator, the more likely you are to develop SAD.

According to the American Psychiatric Association, about 5 percent of adults in the United States experience SAD. For many, this is a recurring condition that visits from late fall to spring, with the most difficult months being January and February.

Although SAD is typically considered a fall and winter disorder, in a small number of cases, symptoms may be triggered by the longer, brighter days of summer. Some people also experience symptoms during periods of overcast weather, regardless of the season.

Shining a light

A diagnosis of SAD is based on your symptoms and history. Symptoms of typical SAD must reoccur at least twice at the same time each year, and then subside for the rest of the year.

“If you have SAD, getting more sunlight may make you feel better,” Dr. Bombard said. “It might be helpful to take walks outdoors or to place yourself near a window during the day when at home or work. If vitamin D levels are low, supplementation is recommended in either over the counter doses or prescription strength depending on the deficiency. Talking to your doctor about getting levels checked is a good place to start.”

If your symptoms are particularly bothersome, light therapy may be recommended.

This involves using special lighting while indoors. Therapeutic lighting is much more intense than standard lighting and has been shown to decrease levels of melatonin in the brain.

Your doctor can help you decide how long to spend in this lighting and the best time of day to do so. For many people with SAD, light therapy is very effective. However, if it does not work for you, your doctor may have other suggestions, including taking medicine for depression.

With proper treatment, SAD is manageable.

Aspirus is a non-profit, community-directed health system based in Wausau, Wisconsin. Aspirus serves communities through four hospitals in Michigan and six hospitals in Wisconsin. For more information, visit aspirus.org.