The short dark days of winter cause some people to experience a distinctive type of depression and malaise. Less often SAD, or seasonal affective disorder, as it is known, causes symptoms in the spring or summer.

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SAD is cyclical—in winter (and sometimes the summer months), SAD sufferers tend to sleep more, be less productive at work, have less energy for recreation, experience changes in sex drive, and feel down in the dumps for no particular reason. They tend to eat more (especially sweets and starches). That, together with a low activity level, generally leads to winter weight gain. They may have trouble getting up in the morning, be irritable, and withdraw from friends and family. Children with SAD may do poorly in school.

From roughly April to the end of October, however, SAD sufferers feel better. Nobody knows how common SAD is, but researchers at the National Institute of Mental Health estimate that it may affect anywhere from 10 to 25 million Americans; at least 80 percent of them are women. Symptoms most commonly start during early adulthood. SAD is thought to be a disorder of the northern latitudes. Oddly, though, Alaskans and Canadians don’t have higher rates of the disorder than those at lower latitudes. SAD seems to run in families, so there may be a genetic link.

The fact is, SAD symptoms are vague, hard to pin down, and very hard to distinguish from other forms of depression. A definition of SAD has been added to the Diagnostic and Statistical Manual of Mental Disorders (the psychiatric bible): you may have the disorder if you have had fall and winter depression for at least two years, alternating with nondepressed periods during spring and summer; at least one disabling depressive episode; no other major psychiatric disorder; and no other possible explanation for the change in mood.

Symptoms of SAD

  • Depressive periods during fall and winter (or spring/summer) seasons. Accompanying symptoms include sleeping more than usual; less energy; tendency to eat more, especially sweets and starches; social withdrawal; fatigue; loss of concentration.
  • Nondepressed periods during other times of the year

What Causes SAD?

Logically enough, many researchers think that changes in the amount of sunlight is at the root of SAD. In general, research has shown that humans have emotional and physiological reactions to changes in the length of the solar day. Daylight is a crucial environmental cue by which humans, like other animals, adapt to the changing seasons and shorter or longer days. Daylight in large part helps to set our circadian rhythms, or biological clocks.

But how the lack of light disturbs us remains a mystery. Bright light apparently affects the production of the hormone melatonin, which may influence both our physical and emotional well-being and may set our sleep patterns. Light deprivation may also disturb the secretion of so-called stress hormones, such as cortisol, which influence how we react to physical and psychological stress.

The belief that light deprivation is behind SAD has led to the development of “light therapy” as one method of treating the condition. Bright, artificial lights are set to emit measured doses of light at a specific distance in order to redress the deprivation.

However, some findings have led researchers to question whether lack of light is indeed the cause of SAD. In fact, according to Dr. Norman Rosenthal, a researcher at the National Institute of Mental Health (and a pioneer in this field as well as a SAD sufferer himself), “neither the etiology of SAD nor the mechanism of the antidepressant effects of light is well understood.”

What If You Do Nothing?

Because SAD symptoms seem vague and inconsistent, it’s not clear how they evolve over the long term. In some people, symptoms gradually improve over time, while in others they remain the same or get worse. Certainly if you don’t feel better, it’s worth trying the measures suggested below.

Home Remedies for SAD

If you think you suffer from SAD or some milder form of seasonal depression, here are some commonsense steps you can take during the winter.

  1. Make your house bright. Trim bushes around your windows and keep the curtains open. Use bright colors on walls and upholstery.
  2. Try to sit near a window if you work in an office and this is an option.
  3. Maximize your daylight time. Get up early.
  4. Get away in winter. Try to take part of your vacation in the winter rather than all of it in the summer. Choose a sunny destination. If you are affected by SAD during the summer months, vacation in a cooler location.
  5. Exercise outdoors. Skiing, for example, is an excellent way to get lots of light. If you exercise indoors, try to do so near a window.
  6. Engage in different social activities and keep doing your normal activities.
  7. Eat a well-balanced diet. Eat foods with sufficient amounts of vitamins and minerals. These foods will give you more energy.
  8. If you try light therapy, be cautious. A whole industry has sprung up to produce and sell battery-powered visors, portable light boxes, special light bulbs, and dawn simulators (lamps that switch on before dawn and gradually light your room, like the sun rising). The Food and Drug Administration (FDA) has warned the manufacturers of light-therapy equipment not to make medical claims for their products—that is, claims that the products can alleviate SAD or winter depression. But many people swear by the benefits of light therapy, despite the lack of strong clinical evidence or well-established guidelines for using it.Keep in mind that, if the light is too concentrated, as in a halogen lamp, it is more likely to cause headache, eyestrain, fatigue, insomnia, irritability or other side effects. Also, tanning lamps and plant lights are not appropriate, since they emit ultraviolet rays and can cause serious eye damage.

Beyond Home Remedies: When To Call Your Doctor

If you suffer from severe winter depression, consider consulting a psychologist or psychiatrist.

What Your Doctor Will Do

A qualified doctor or other specialist will interview you to assess if your mood problems and other symptoms are seasonally related or have some other cause. The doctor will then help coordinate your anti-SAD efforts, which can range from psychotherapy and stress-management techniques to antidepressant drugs and perhaps light therapy. Some medical insurance covers light therapy after a diagnosis of SAD.


The Complete Home Wellness Handbook

John Edward Swartzberg, M.D., F.A.C.P., Sheldon Margen, M.D., and the editors of the UC Berkeley Wellness Letter

Updated by Remedy Health Media

Publication Review By: the Editorial Staff at

Published: 08 Nov 2011

Last Modified: 10 Sep 2015