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Seasonal affective disorder (SAD)

Seasonal affective disorder (SAD)

Seasonal affective disorder (SAD) is a type of depression that is triggered by a change in seasons, especially when autumn arrives, and notably in European countries. This seasonal depression worsens in late autumn or early winter, before eventually subsiding in the warmer days of spring.

A mild form of SAD known as the "winter blues" can also occur. It's normal to feel down during the colder months. You could be trapped indoors, and it could get dark early.

However, the full SAD goes beyond this. It is a type of depression. In contrast to the winter blues, SAD has an impact on your daily life, including how you feel and think. Fortunately, treatment can help you get through this difficult period.

Seasonal affective disorder (SAD) is also referred to as seasonal depression.

Some people suffer from a rare form of SAD known as "summer depression." It begins in late spring or early summer and lasts until the fall. It is less common than seasonal affective disorder, which typically occurs in the winter.

SAD affects about 5% of adults in the United States. It usually begins in early adulthood (usually between the ages of 18 and 30). Researchers are unsure why SAD affects women more than men.

Symptoms of seasonal affective disorder

The American Psychiatric Association classifies SAD as a major depressive disorder with seasonal patterns. So, if you have seasonal affective disorder, you will experience mood swings and depression symptoms:

The two types of SAD are winter-pattern and summer-pattern. Summer-pattern SAD occurs in around 10 percent of cases.

Symptoms of both types last around 4 to 5 months, and may include:

●     depression

●     difficulty sleeping

●     lack of energy

●     trouble concentrating

●     thoughts of suicide

Symptoms of winter-pattern SAD:

●     daytime fatigue

●     overeating

●     lack of interest in social activities

●     weight gain

Symptoms of summer-pattern SAD:

●     agitation

●     difficulty sleeping

●     increased restlessness

●     lack of appetite

●     Weight loss

●     acting violently


Researchers aren't sure what causes seasonal depression. If you are prone to the condition, a lack of sunlight may precipitate it.

➔    Change in biological clock: When there is less sunlight, your biological clock shifts. This internal clock controls your mood, sleep, and hormone levels. When it shifts, you're out of sync with your daily routine and unable to adjust to changes in daylight length.

➔    A chemical imbalance in the brain causes communication between nerves to be disrupted. Serotonin, which contributes to feelings of happiness, is one of these chemicals. You may already have lower serotonin activity if you are at risk of SAD, and because sunlight helps regulate serotonin, a lack of sunlight during the winter can exacerbate the situation. Serotonin levels may fall even further, resulting in depression.

➔    Vitamin D deficiency: Vitamin D boosts your serotonin levels as well. Because sunlight aids in the production of vitamin D, a lack of sunlight during the winter can result in a vitamin D deficiency. This change can have an impact on your serotonin levels and mood.

➔    Melatonin supplementation: Melatonin is a chemical that influences your sleep and mood. In some people, a lack of sunlight may cause an overproduction of melatonin. During the winter, you may feel sluggish and sleepy.

➔    Negative thoughts: People suffering from SAD frequently experience stress, anxiety, and negative thoughts about the winter. Researchers are unsure whether these negative thoughts are a cause or a result of seasonal depression.

Now put on your thinking hats and think about the following questions for a couple of minutes.

How would you explain the term “Seasonal affective disorder” to your students?

Can you think of some factors that may contribute to Seasonal affective disorder?

Write down your thoughts and discuss them with your students, children, and your colleagues. Listen to their views and compare them with your own. As you listen to others, note how similar or different your views are to others’.

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Happy Teaching!