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NCCIH Clinical Digest

for health professionals

Seasonal Affective Disorder and Complementary Health Approaches

January 2019
Seasonal Affective Disorder

Seasonal Affective Disorder (SAD), a type of depression that comes and goes with the seasons, typically starts in the late fall and early winter and goes away during the spring and summer. Depressive episodes linked to the summer can occur but are much less common than winter episodes of SAD. Some of the symptoms of the winter pattern of SAD include having low energy, overeating, craving carbohydrates, and social withdrawal. Light therapy has become a standard treatment of SAD, and antidepressants have also been shown to improve SAD symptoms.

Some people turn to complementary health approaches to prevent SAD, including light therapy, cognitive behavioral therapy – SAD, St. John’s wort, melatonin, and vitamin D. This issue of the digest provides the summary of current research for these modalities.

Modality and Summary of Current Research

There is some evidence that light therapy may be useful as a preventive treatment for people with a history of season affect disorder.

Read more about Light Therapy

There is some evidence that cognitive behavioral therapy – SAD can be effective in reducing the recurrence and remissions of SAD and has been shown to be sustained at least between a first and second winter season.

Read more about Cognitive Behavioral Therapy (CBT-SAD)

There is limited evidence that St. John’s wort may improve some symptoms of SAD; however, the studies have been small.

Read more about St. John’s wort

There is some limited evidence (small trials involving few patients) that suggests melatonin improves sleep in patients with SAD; however, no definite conclusions about its effectiveness can be made.

Read more about Melatonin

At present, vitamin D supplementation by itself is not considered an effective SAD treatment.

Read more about Vitamin D

NCCIH Clinical Digest is a service of the National Center for Complementary and Integrative Health, NIH, DHHS. NCCIH Clinical Digest, a monthly e-newsletter, offers evidence-based information on complementary health approaches, including scientific literature searches, summaries of NCCIH-funded research, fact sheets for patients, and more.

The National Center for Complementary and Integrative Health is dedicated to exploring complementary health products and practices in the context of rigorous science, training complementary health researchers, and disseminating authoritative information to the public and professionals. For additional information, call NCCIH’s Clearinghouse toll-free at 1-888-644-6226, or visit the NCCIH website at NCCIH is 1 of 27 institutes and centers at the National Institutes of Health, the Federal focal point for medical research in the United States.


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