What is Seasonal Affective Disorder (SAD)?


I think it’s worse this year, but there are a few other things going on that are exacerbating my symptoms.   I seem to have a weird form of it, which starts in late July or August, when my body begins to notice the reduction of light, even though summer is at its peak. Even though I detest winter, my mood starts to pick up in late January or February, when my body notices the lengthening days. I’m at my best in April – June and at my worst in November and December. My SAD seems to imitate the sleep/wake patterns of hibernating animals.

Graph I made showing my moods throughout the year. This never varies much.

Here’s an overview of what SAD is, from mayoclinic.org.

Seasonal Affective Disorder (SAD)


Seasonal affective disorder (SAD) is a type of depression that’s related to changes in seasons — SAD begins and ends at about the same times every year. If you’re like most people with SAD, your symptoms start in the fall and continue into the winter months, sapping your energy and making you feel moody. Less often, SAD causes depression in the spring or early summer.

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

Don’t brush off that yearly feeling as simply a case of the “winter blues” or a seasonal funk that you have to tough out on your own. Take steps to keep your mood and motivation steady throughout the year.


By Mayo Clinic Staff

In most cases, seasonal affective disorder symptoms appear during late fall or early winter and go away during the sunnier days of spring and summer. However, some people with the opposite pattern have symptoms that begin in spring or summer. In either case, symptoms may start out mild and become more severe as the season progresses.

Major depression

Seasonal affective disorder is a subtype of major depression that comes and goes based on seasons. So symptoms of major depression may be part of SAD, such as:

Feeling depressed most of the day, nearly every day
Feeling hopeless or worthless
Having low energy
Losing interest in activities you once enjoyed
Having problems with sleeping
Experiencing changes in your appetite or weight
Feeling sluggish or agitated
Having difficulty concentrating
Having frequent thoughts of death or suicide

Fall and winter SAD

Symptoms specific to winter-onset SAD, sometimes called winter depression, may include:

Tiredness or low energy
Problems getting along with other people
Hypersensitivity to rejection
Heavy, “leaden” feeling in the arms or legs
Appetite changes, especially a craving for foods high in carbohydrates
Weight gain

Spring and summer SAD

Symptoms specific to summer-onset seasonal affective disorder, sometimes called summer depression, may include:

Trouble sleeping (insomnia)
Weight loss
Poor appetite
Agitation or anxiety


Seasonal changes in bipolar disorder

In some people with bipolar disorder, spring and summer can bring on symptoms of mania or a less intense form of mania (hypomania), and fall and winter can be a time of depression.

When to see a doctor

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 doctor. This is especially important if your sleep patterns and appetite have changed or if you feel hopeless, think about suicide, or turn to alcohol for comfort or relaxation.


By Mayo Clinic Staff

The specific cause of seasonal affective disorder remains unknown. Some factors that may come into play include:

  • Your biological clock (circadian rhythm). The reduced level of sunlight in fall and winter may cause winter-onset SAD. This decrease in sunlight may disrupt your body’s internal clock and lead to feelings of depression.
  • Serotonin levels. A drop in serotonin, a brain chemical (neurotransmitter) that affects mood, might play a role in SAD. Reduced sunlight can cause a drop in serotonin that may trigger depression.
  • Melatonin levels. The change in season can disrupt the balance of the body’s level of melatonin, which plays a role in sleep patterns and mood

Risk Factors

Factors that may increase your risk of seasonal affective disorder include:

  • Being female. SAD is diagnosed more often in women than in men, but men may have more-severe symptoms.
  • Age. Young people have a higher risk of winter SAD, and winter SAD is less likely to occur in older adults.
  • Family history. People with SAD may be more likely to have blood relatives with SAD or another form of depression.
  • Having clinical depression or bipolar disorder. Symptoms of depression may worsen seasonally if you have one of these conditions.
  • Living far from the equator. SAD appears to be more common among people who live far north or south of the equator. This may be due to decreased sunlight during the winter and longer days during the summer months.


Take signs and symptoms of seasonal affective disorder seriously. As with other types of depression, SAD can get worse and lead to problems if it’s not treated. These can include:

  • Suicidal thoughts or behavior
  • Social withdrawal
  • School or work problems
  • Substance abuse

Treatment can help prevent complications, especially if SAD is diagnosed and treated before symptoms get bad.

Original article is here.



14 thoughts on “What is Seasonal Affective Disorder (SAD)?

  1. TEN star excellent post. I pinned your Winter/Summer SAD graphic to my Depression & BiPolar board for a quick way to get back here when I’m ready to take on the topic of Depression on my blog (as you probably know, pins link to originating posts). Thank you so much for putting this together.
    (Madelyn Griffith-Haynie – ADDandSoMuchMore dot com)
    – ADD Coach Training Field founder; ADD Coaching co-founder –
    “It takes a village to educate a world!”

    Liked by 1 person

      • You’re welcome. I have known for 25 years that disrupted chronorhythms and resulting hormonal changes due to differing light exposure can cause depression in the winter and, as you point out, hypomanic states in the summer – and not just for the diagnostically bipolar. For some, ADD/EFD hyperactivity can be exacerbated in the summer.

        I’m always surprised when I become aware of people who are unaware of SAD – and dismayed when they disbelieve that it is an authentic problem.

        Liked by 1 person

  2. This is great information. I used to think this only happened in Winter, but I am beginning to see how it can affect a person potentially year round.

    Liked by 1 person

  3. Good info. I shut down from November until May. I’m not diagnosed with this, nor do I wish to jump on the bandwagon, but just wanted to let you know I understand. I literally feel empty inside all winter, like my existing doesn’t even matter, until Springtime. That’s why I don’t like Fall, I know my soul will be sad in the months following it. It’s like I go to sleep like the trees do.

    Liked by 1 person

  4. I think I have a mild form of this. I notice my mood starts to go down when the days get noticeably shorter and begin to perk back up when the days get longer.

    For me, it doesn’t get really bad until it’s cold enough out to have the heat on in the house. The sound of the central heat cycling on and off at night is a terrible reminder of the winter when I was a child and my mom turned off the heat and turned the gas up all the way so that we would die in our sleep. Only, I wasn’t asleep…


  5. Lauren Greece is a common destination for people with SAD in Switzerland amd Germany.
    I also think Nov is the worst month of the year .
    Hugs ⭐️☀️

    Liked by 1 person

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