Understand Seasonal Affective Disorder (SAD)

Seasonal affective disorder, or seasonal depression, affects millions of people every year. Often referred to as “wintertime blues” this disorder can have a severe impact on an individual’s day-to-day life.

Our article will explain what seasonal affective disorder is, its symptoms, risk factors and treatment options.

What Is Seasonal Affective Disorder?

Seasonal affective disorder (SAD) is a type of seasonal depression that begins and ends around the same time every year, typically linked to changes in seasons. For most people, this seasonal mood change begins as the summer ends and daylight begins to fade, and then improves in the spring. However, some people experience this seasonal emotional cycle with low points in the spring and summer. SAD is more commonly diagnosed in women than men, although both genders are affected by the condition.

SAD is considered a subtype of major depression or bipolar disorder, and has certain markers that differentiate it from other major depression types. These include:

  • Depression begins at a specific point in the year.
  • Depression ends around the same point in the year.
  • The individual does not experience clinical depression during the time of year when they would not otherwise be depressed.
  • More regular seasons with depression than without occur during the course of illness.

What Are the Symptoms of SAD?

According to the National Institute of Mental Health (NIMH) The symptoms of seasonal affective disorder are ones most often associated with depression, but are experienced on a seasonal basis.

Symptoms of major depression include:

  • Low mood, numbness, or sadness.
  • Grumpiness, restlessness, or irritability.
  • Anxiety or excessive worry.
  • Physical aches and pains.
  • Persistent exhaustion or fatigue.
  • Difficulty concentrating.
  • Loss of enjoyment or interest in previously enjoyed activities or hobbies
  • Thoughts of self-harm or suicide.

For individuals with winter-pattern SAD, additional symptoms may include:

  • Sleeping too much (hypersomnia).
  • Overeating and weight gain.
  • Cravings for carbohydrates.
  • Social isolation.

Symptoms for summer-pattern seasonal affective disorder may include:

  • Insomnia.
  • Poor appetite.
  • Weight changes.
  • Restless and irritability.
  • Anxiety.

How Is SAD Diagnosed?

Seasonal affective disorder is diagnosed by a healthcare professional. Generally speaking, a diagnosis is made after:

  1. A physical exam is conducted, to rule out underlying medical conditions
  2. Lab tests are performed especially of blood or urine, to determine thyroid functioning
  3. Psychological evaluation, including a questionnaire, to determine the individual’s pattern of thoughts, feelings, and behaviors

Once the physician or therapist has determined that the individual has SAD, their depression is not due to another cause, and it is specifically triggered by seasonal changes, they will work with the client to develop an appropriate treatment plan.

In some instances, a physician will also examine a person’s seasonal eating habits. Cravings for calorie-dense foods, especially carbohydrates, which provide quick bursts of energy, is considered by some doctors to be one of the symptoms of SAD. Cravings for calorie-dense foods, lack of energy to exercise, and overeating in an attempt to restore energy lead to rapid weight gain; the person will then typically shed the weight, or much of the weight, during the non-depressed seasons. However, cravings and weight gain can also relate to other underlying conditions, so blood tests and a physical exam are important tools for ruling these problems out.

What Causes SAD?

Research into the cause of seasonal affective disorder is ongoing, but the current consensus is that the amount of daylight a person gets during specific months in the year can affect how their brain produces neurotransmitters — particularly serotonin — and other hormones. When the brain produces less serotonin, neural pathways do not communicate as they should or as they do during normal levels of processing, which can lead to depression, weight gain, fatigue, and other symptoms.

These changes in neurotransmitter levels can be exacerbated by light-related changes to circadian rhythm or a person’s natural cycle of sleeping and waking. People prone to “summer depression” may get less sleep, for example, when the sun rises much earlier and sets later.

Another theory about SAD involves melatonin production, which helps control sleep and wake cycles. The amount of light a person receives during the day affects when their pineal gland begins to produce melatonin. If the person gets only a few hours of daylight during the winter months, for example, their pineal gland may begin producing melatonin much earlier in the day, making them feel fatigued. This can also disrupt normal sleep cycles and cause the person to lose sleep, adding to fatigue.

Risk Factors for Seasonal Affective Disorder

People can experience SAD in both the winter and summer, or they could develop the condition if they move to an area where there is a different amount of natural light over the course of the year. Some people are generally more prone to developing this condition than others, such as:

  • Women.
  • People who live further from the equator and get much less daylight during the winter months.
  • Teenagers, young adults, and middle-aged individuals (between the ages of 15 and 55, most commonly).
  • People with an existing mood disorder, especially depression or bipolar disorder.
  • Those with family members who struggle with a mood disorder, especially SAD.

How Is Seasonal Affective Disorder Treated?

Once a person has been diagnosed with SAD, their physician or therapist will begin different treatments and work to improve these over time, depending on the severity of the disorder. Some of these treatments include:

Light Therapy

This comes in the form of either spending different amounts of time outside or using a light box. People who struggle with SAD during the summer will receive different treatments, but for the more common winter-pattern form of SAD, spending more time outside during daylight hours has been found to be an effective treatment for mild forms of the condition.

People who experience more intense symptoms may receive a prescription for a light box and given a specific amount of time (at least 30 minutes) to use the device per day. By mimicking sunlight and important UV rays, the light box can help the body stabilize hormonal cycles, maintain circadian rhythm and melatonin production, and improve mood by stabilizing neurotransmitters like serotonin. Light therapy is often recommended to help people wake up in the morning, especially if the individual must get up before the sun rises.

Lifestyle Changes

Maintaining a healthier diet full of fruits, vegetables, and lean proteins can help prevent the ups and downs related to carbohydrate consumption. Changing the quality of carbohydrates – such as cutting sugar and eating whole wheat bread – can also reduce the intensity of these dietary hormonal fluctuations. Additionally, exercise helps release and balance neurotransmitters, so regular exercise will improve and stabilize moods.

If SAD is often coupled with anxiety, other lifestyle changes, such as meditation, biofeedback therapy, yoga, or stress management techniques, can be helpful.

Talk Therapy

People who experience intense mood changes through the seasons may benefit from talk therapy to help them recognize when their mood begins to change, so they can implement light therapy or focus on lifestyle changes before they feel too depressed.


A person who experiences intense, seasonal mood fluctuations may also benefit from a routine antidepressant, such as Paxil, Prozac, or Zoloft. As these medications stabilize neurotransmitters throughout the year, this can help maintain brain chemistry through seasonal changes. Additionally, people with milder forms of summer depression may take melatonin supplements, which can help regulate their sleep cycles without the influence of daylight.

What Happens When SAD Is Untreated?

Any mood disorder that goes untreated, including SAD, can get worse. People who struggle with mood disorders such as depression, anxiety, and bipolar disorder are more prone to developing substance use disorders.

Substance use disorders often co-occur with mental health disorders, a condition called co-occurring disorders. While mental illness does not cause substance use disorders (or vice versa), substance misuse can exacerbate symptoms of mental health disorders. Conversely, in an effort to self-medicate symptoms, a person struggling with seasonal affective disorder may turn to drugs or alcohol. Furthermore, individuals can sometimes become addicted to mood-changing prescription medications, particularly benzodiazepines like Xanax, that are not intended for long-term use.

Treatment for Co-Occurring SAD and Addiction

Since addiction and mental health disorders are often closely intertwined, it is important that both disorders are treated. For individuals struggling with mental health disorders — including seasonal affective disorder — and addiction getting integrated treatment that addresses both disorders simultaneously has the greatest benefit.

Sunrise House offers effective evidence-based co-occurring disorder treatment at our inpatient rehab in Lafayette, NJ. To learn more about our different levels of care and your treatment options, contact our knowledgeable and helpful admissions navigators at 24/7. They can also give you more information about using insurance for rehab and help you start the admissions process.

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