Causes, symptoms and cure for Seasonal Affective Disorder (SAD)

Seasonal depression, also known as seasonal affective disorder (SAD), is a mood disorder that happens every year at about the same time. It usually starts in fall or winter and ends in spring or early summer. These mood changes may affect how you feel, think, and act.

According to media reports, more than 10 million people in India suffer from SAD, a condition where the season and the associated weather affects the mood of a person.

SAD usually starts in the fall and continues into the winter months, sapping people of their energy, making them feel moody. But these symptoms usually resolve during the spring and summer months. A rare form of seasonal depression, known as "summer depression," begins in late spring or early summer and ends in fall.

Also read | Seasonal affective disorder causes and tips to deal with this type of depression

• What causes Seasonal Depression

While the exact causes of SAD are unknown, scientists and doctors speculate that is it triggered by attitude-related changes at certain times of the year. One theory is that less sunlight during fall and winter months leads your brain to make less serotonin, a chemical linked to brain pathways that help control mood. When these nerve cell pathways don't work the way they should, it can result in feelings of depression, along with fatigue and weight gain.

“The real reason for SAD is unknown. Although, in India, the scorching summer and gloomy winters are the marked seasons when people feel either low, irritable or out of place because of the weather. The monsoon can also cause a sufficient amount of irritation in a person mere thinking of the inconveniences. The natural biological clock is affected and further causes changes in the mood,” Kolkata-based clinical psychologist Shinjini Deb told Hindustan Times.

Because SAD that starts in winter is related to the reduced levels of daylight, it's less often found in countries where there's plenty of sunshine year-round.

“The prevailing hypothesis is that reduced exposure to natural sunlight during these seasons disrupts circadian rhythms and affects neurotransmitter levels, particularly serotonin and melatonin,” according to Dr Shambhavi Jaiman, Consultant Psychiatrist Department of Mental Health and Behavioural Sciences, Fortis Healthcare, in many media reports.

It's not clear what causes SAD that starts in spring or summer. Some experts believe it's linked to higher levels of light that may disrupt sleep patterns. It also may be linked to increased social pressures, as more events are scheduled during warm weather.

Also read | How to recognize and address seasonal depression

Seasonal Depression Symptoms

People with SAD typically sleep much more than usual and crave carbohydrates. They also have many of the normal warning signs like:

• Feeling sad or down most of the time
• Less energy
• Trouble concentrating
• Fatigue
• Increased appetite
• More desire to be alone
• Thoughts of suicide
• Loss of interest in things you used to enjoy
• Sleeping too much
• Overeating and weight gain
• Feelings of guilt or worthlessness

• Seasonal Depression Treatment

Treatments differ, depending on how serious your seasonal affective disorder symptoms are. The type of treatment you get also depends on whether you have another type of depression or bipolar disorder.

Low levels of vitamin D have been found in people with SAD. It may be caused either by getting too little of the vitamin in your diet or not getting enough sunshine. But it's unclear whether vitamin D supplements can help ease SAD symptoms. Very little research has been done on dietary supplements other than vitamin D for SAD.

One of the most effective ways to treat SAD that starts in fall or winter is with light. Light affects our brain's biological clock, which regulates the circadian rhythm — a physiological process that can lead to mood changes in winter when there’s less sunlight. Natural or "full-spectrum" light can have an antidepressant effect

According to the US-based Mayo Clinic, “It's normal to have some days when you feel down. But if you feel down for days at a time and you can't get motivated to do activities you normally enjoy, see your health care provider. This is especially important if your sleep patterns and appetite have changed, you turn to alcohol for comfort or relaxation, or you feel hopeless or think about suicide.”

DISCLAIMER: This article, including health and fitness advice, only provides generic information. Don’t treat it as a substitute for qualified medical opinion. Always consult a specialist for specific health diagnosis.