Where is sad most common

Want to use this article elsewhere? Get Permissions. Read the Issue. Sign Up Now. Mar 1, Issue. Am Fam Physician. What is seasonal affective disorder?

Do many people get SAD? How does my doctor know I have SAD? Not everyone with SAD has the same symptoms, but common symptoms of winter depression include the following: A change in appetite, especially a craving for sweet or starchy foods Weight gain A heavy feeling in the arms or legs A drop in energy level Fatigue A tendency to oversleep Difficulty concentrating Irritability Increased sensitivity to social rejection Avoidance of social situations—not wanting to go out Symptoms of the summer version of SAD are poor appetite, weight loss and insomnia.

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Overview Seasonal affective disorder is a type of depression that occurs during the same season each year. Other symptoms of depression include: changes in appetite and weight sleep problems loss of interest in work, hobbies, people or sex withdrawal from family members and friends feeling useless, hopeless, excessively guilty, pessimistic or having low self-esteem agitation or feeling slowed down irritability fatigue trouble concentrating, remembering and making decisions crying easily or feeling like crying but not being able to thoughts of suicide which should always be taken seriously a loss of touch with reality, hearing voices hallucinations or having strange ideas delusions.

Changes in light may: upset a person's biological clock, which controls sleep-wake patterns disturb neurotransmitter e. SAD is more common in people who live either far north or far south of the equator. Young people are more likely to develop SAD.

The risk decreases with age. A family history of SAD or other forms of depression increases risk. Side-effects of light therapy are usually mild. They include: nausea headaches eye strain. The symptoms usually occur during the fall and winter months when there is less sunlight and usually improve with the arrival of spring. While it is much less common, some people experience SAD in the summer. However, it can be treated.

About 5 percent of adults in the U. It is more common among women than men. SAD has been linked to a biochemical imbalance in the brain prompted by shorter daylight hours and less sunlight in winter. As seasons change, people experience a shift in their biological internal clock or circadian rhythm that can cause them to be out of step with their daily schedule. SAD is more common in people living far from the equator where there are fewer daylight hours in the winter. Common symptoms of SAD include fatigue, even with too much sleep, and weight gain associated with overeating and carbohydrate cravings.

SAD symptoms can vary from mild to severe and can include many symptoms similar to major depression, such as:. SAD is more common in people who have relatives with other mental illnesses, such as major depression or schizophrenia. Scientists do not fully understand what causes SAD.

Research indicates that people with SAD may have reduced activity of the brain chemical neurotransmitter serotonin, which helps regulate mood. Research also suggests that sunlight controls the levels of molecules that help maintain normal serotonin levels, but in people with SAD, this regulation does not function properly, resulting in decreased serotonin levels in the winter.

Other findings suggest that people with SAD produce too much melatonin—a hormone that is central for maintaining the normal sleep-wake cycle. Overproduction of melatonin can increase sleepiness. In people with SAD, the changes in serotonin and melatonin levels disrupt the normal daily rhythms. As a result, they can no longer adjust to the seasonal changes in day length, leading to sleep, mood, and behavior changes. Deficits in vitamin D may exacerbate these problems because vitamin D is believed to promote serotonin activity.

In addition to vitamin D consumed with diet, the body produces vitamin D when exposed to sunlight on the skin. With less daylight in the winter, people with SAD may have lower vitamin D levels, which may further hinder serotonin activity. Negative thoughts and feelings about the winter and its associated limitations and stresses are common among people with SAD as well as others.

It is unclear whether these are "causes" or "effects" of the mood disorder, but they can be a useful focus of treatment. Treatments are available that can help many people with SAD. They fall into four main categories that may be used alone or in combination:. Talk to your health care provider about which treatment, or combination of treatments, is best for you. Since the s, light therapy has been a mainstay for the treatment of SAD.

It aims to expose people with SAD to a bright light every day to make up for the diminished natural sunshine in the darker months. For this treatment, the person sits in front of a very bright light box 10, lux every day for about 30 to 45 minutes, usually first thing in the morning, from fall to spring.

The light boxes, which are about 20 times brighter than ordinary indoor light, filter out the potentially damaging UV light, making this a safe treatment for most. However, people with certain eye diseases or people taking certain medications that increase sensitivity to sunlight may need to use alternative treatments or use light therapy under medical supervision.

It is typically conducted in two weekly group sessions for 6 weeks and focuses on replacing negative thoughts related to the winter season e. CBT-SAD also uses a process called behavioral activation, which helps individuals identify and schedule pleasant, engaging indoor or outdoor activities to combat the loss of interest they typically experience in the winter.

When researchers directly compared CBT with light therapy, both treatments were equally effective in improving SAD symptoms.