Seasonal depression or Seasonal affective disorder, is a type of 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. Seasonal affective disorder, often abbreviated to SAD, is more commonly diagnosed in women than men, although both genders are affected by the condition.
What is seasonal affective disorder?
Seasonal depression, or seasonal affective disorder, is caused by changes in brain chemistry or hormonal cycles, which scientists believe to be influenced by the amount of daylight during the year. Symptoms of SAD appear similar to those of depression, although at a regular point in the year, mood lifts and the individual feels better. Physicians typically diagnose SAD if the individual experiences patterns of depression and mood lifting at similar times of year for at least two years in a row.
SAD is considered a subtype of major depression or bipolar disorder. In order to diagnose SAD appropriately and separate this mood disorder from other potential mood disorders, the DSM-5 requires the following criteria:
- 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?
Symptoms of SAD must recur on a regular pattern for at least two years in order to be diagnosed as a mood disorder. The symptoms are similar to dysthymia or depression and include:
- Low mood, numbness, or sadness
- Grumpiness, restlessness, or irritability
- Anxiety or excessive worry
- Craving and eating calorie-dense foods, especially carbohydrates
- Weight gain
- Excessive sleep
- Persistent exhaustion or fatigue
- Inability to sleep regularly
- Difficulty concentrating
- Loss of enjoyment or interest in previously enjoyed activities or hobbies
- Thoughts of self-harm or suicide
What causes SAD?
Researchers argue about exactly what causes SAD, but most agree that the amount of daylight a person gets during specific months in the year can affect how their brain produces neurotransmitters, particularly serotonin, or how their body produces 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.
Who is at risk for developing SAD?
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:
- 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 it diagnosed?
There are three ways a physician will diagnose SAD:
- Physical exam, to rule out underlying medical conditions
- Lab tests, especially of blood or urine, to determine thyroid functioning
- 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.
How is it 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 form of SAD, which occurs during the winter, 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.
- Other 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 mood. 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.
- Medication: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?
Seasonal affective disorder is commonly discussed in the media, and because of that, many people may self-diagnose as suffering from SAD without understanding how serious this condition can be. Although there are milder versions of SAD, only about 1-2 percent of the population has actually received a diagnosis of SAD. There are probably many people who have not received a diagnosis or who struggle with another mood disorder but believe it to be SAD. It is important to get help immediately for persistent mood problems like recurring anxiety or persistent low mood, especially when these issues begin to interfere with life, work, and relationships.
Any mood disorder that goes untreated can get worse. People who struggle with mood disorders such as depression, including SAD, anxiety, and bipolar disorder, are more prone to developing substance abuse and addiction problems. This is because people who struggle with persistent or recurrent mood changes might attempt to self-medicate, especially with alcohol. However, these individuals can sometimes become addicted to mood-changing prescription medications, particularly benzodiazepines, that are not intended for long-term use.
Treatment for Co-Occurring SAD and Addiction
People who struggle with both a substance abuse problem and a mental health issue, such as SAD, have co-occurring disorders. These conditions feed into each other, and each disorder can make symptoms of the other disorder worse. Getting professional help is the best way to overcome these issues. Since the link between addiction and mental health is becoming more understood, doctors and rehabilitation programs are much more prepared to help people struggling with these two conditions simultaneously.