Seasonal affective disorder (SAD)

Seasonal affective disorder (SAD)

Seasonal affective disorder (SAD)

Seasonal affective disorder (SAD) is a form of depression that is estimated to affect approximately one in 15 people between September and April. It can be particularly severe during December, January and February. For some people, SAD is so disabling that they cannot function in winter without continuous treatment. Others may experience a milder version called sub-syndromal SAD or ‘winter blues’.

It occurs throughout the northern and southern hemispheres but is extremely rare in people living within 30 degrees of the Equator, where daylight hours are long, constant and extremely bright.

What are the symptoms of SAD?

SAD may begin at any age, but it most commonly starts between 18 and 30. Symptoms generally appear between September and November and continue until March or April, when there may be a sudden burst of energy and activity accompanying the longer, brighter spring and summer days. A diagnosis is usually made after you’ve experienced two or more consecutive winters of symptoms.

Common symptoms include:

  • sleep problems – usually oversleeping and difficulty staying awake but in some cases disturbed sleep and early morning waking
  • lethargy – lacking in energy and unable to carry out normal routine due to fatigue. Heaviness in the arms and legs overeating – craving for carbohydrates and sweet foods, which usually leads to weight gain
  • depression – feeling sad, low and weepy, a failure, sometimes hopeless and despairing
  • apathy – loss of motivation and ability to concentrate
  • social problems – irritability and withdrawal from social situations, not wanting to see friends
  • anxiety – feeling tense and unable to cope with stress
  • loss of interest in normally pleasurable activities
  • loss of libido – decreased interest in sex and physical contact
  • weakened immune system – vulnerability to catching winter colds and flu
  • mood changes – for some people bursts of over-activity and cheerfulness (known as hypo-mania) in spring and autumn.

Six treatments for SAD


1 Maximize your exposure to daylight. Make your house brighter—trim the bushes around your windows and keep your blinds and curtains open during the day. Use bright colors on walls and light-colored upholstery. Get up early to take advantage of as much daylight as possible. If possible, sit near a window at work.

2 Engage in activities that you enjoy. Take some time off in the winter, instead of using all of your vacation time during the summer. Volunteer or participate in activities that make you happy. Spend time with friends and family members who are caring, supportive, and positive.

3 Practice healthy habits. Exercise, get enough sleep, eat a well-balanced diet, and reduce stress. Spend time outdoors if possible—skiing is an excellent way to get lots of light and exercise in the winter. Practice good sleep hygiene and make time to relax. Eat healthy foods for more energy and limit caffeine and alcohol.

4 Take all medicines as directed. Talk to your GP about prescription and over-the-counter (OTC) drugs and diet supplements (including vitamin D), as well as any herbs you may take. Follow directions carefully and watch for interactions and side effects. Avoid alcohol and illegal drugs.

5 Consider light therapy. There are several devices available—from battery-powered visors, portable light boxes and special light bulbs, to dawn simulators (lamps that switch on before dawn and gradually light your room, like the sun rising)— You should talk to your GP before trying light therapy.

6 Watch for early signs that SAD is getting worse. If you suffer from severe winter depression, consult your GP immediately. A qualified health care provider can help determine if your symptoms are related to SAD or may have another cause. Additional treatments available include psychotherapy, behavioral therapy, stress management techniques and prescribed medication.

Plan to protect your mental health and wellbeing:


Be active

Take notice

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