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National Institutes of Health • National Center for Complementary and Alternative Medicine

NCCAM Clinical Digest

Depression and Complementary Health Practices :
What the Science Says

December 2011

Depression has several forms, and its symptoms and severity can vary from person to person. For example:

  • Major depression (also called major depressive disorder) is characterized by a depressed mood and/or a loss of interest in nearly all activities consistently for at least 2 weeks. People with major depression may also experience a variety of other symptoms such as loss of appetite, fatigue, sleep disturbance, irritability, difficulty concentrating, and thoughts of death or suicide.
  • Dysthymia (also called dysthymic disorder) is a less severe, but more chronic form of depression. People with dysthymia experience symptoms that are not as disabling but keep them from functioning well or feeling good. Symptoms last at least 2 years. Many people with dysthymia also have episodes of major depression.
  • Bipolar disorder (also called manic-depressive illness) is a condition in which people have periods of depressive symptoms that alternate or may co-exist with periods of abnormally high levels of excitement and energy, racing thoughts, and behavior that is impulsive and inappropriate.

In addition, milder forms of depression exist that fall into the category of minor depression. In minor depression, people experience the same symptoms as major depression, but they are fewer in number and are less disabling. Symptoms last at least 6 months but less than 2 years continuously.

Dietary Supplements

Omega-3 Fatty Acids

Scientific Evidence

  • NCCAM-sponsored studies have been investigating the effects of omega-3 fatty acids/fish oil on major depression in adults, adolescent depression, and depression in people with multiple sclerosis. More research is needed to determine whether omega-3 fatty acids help symptoms of depression.

Side Effects and Cautions

  • Omega-3s appear to be safe for most adults at low-to-moderate doses. The FDA has concluded that omega-3 dietary supplements from fish are “generally recognized as safe.”
  • Some have questioned the safety of fish oil supplements because some species of fish can contain high levels of mercury, pesticides, or polychlorinated biphenyls (PCBs). However, fish oil supplements do not appear to contain these substances.
  • Fish oil supplements may cause minor gastrointestinal upsets, including diarrhea, heartburn, indigestion, and abdominal bloating.
  • In high doses, fish oil can interact with certain medications, including blood thinners and drugs used for high blood pressure.

St. John’s Wort

Scientific Evidence

  • Although some studies have reported benefits for more severe depression, others have not. For example, a large study sponsored by NCCAM, the National Institute of Mental Health (NIMH), and the Office of Dietary Supplements found that the herb was no more effective than placebo in treating major depression of moderate severity, and a study co-funded by NCCAM and NIMH found that neither St. John’s wort nor a standard antidepressant medication relieved symptoms of minor depression better than placebo.

Side Effects and Cautions

  • St. John’s wort may cause increased sensitivity to sunlight. Other side effects can include anxiety, dry mouth, dizziness, gastrointestinal symptoms, fatigue, headache, or sexual dysfunction.
  • Research has shown that St. John’s wort interacts with many medications in ways that can interfere with their intended effects. Examples of medications that can be affected include:
    • Antidepressants
    • Birth control pills
    • Cyclosporine, which prevents the body from rejecting transplanted organs
    • Digoxin, a heart medication
    • Indinavir and possibly other drugs used to control HIV infection
    • Irinotecan and possibly other drugs used to treat cancer
    • Seizure-control drugs, such as phenytoin and phenobarbital
    • Warfarin and related anticoagulants.
  • Taking St. John’s wort with certain antidepressants may lead to increased serotonin-related side effects, which may be potentially serious.


Scientific Evidence

  • There is not enough scientific evidence to determine whether valerian works for anxiety or depression.

Side Effects and Cautions

  • Studies suggest that valerian is generally safe to use for short periods of time (for example, 4 to 6 weeks).
  • No information is available about the long-term safety of valerian.
  • Valerian can cause mild side effects, such as headaches, dizziness, upset stomach, and tiredness the morning after its use.

Other Complementary Health Practices


Scientific Evidence

  • Although scientific research on massage therapy in general—whether it works and, if so, how—is limited, there is evidence that massage may benefit some patients. Conclusions generally cannot yet be drawn about its effectiveness for specific health conditions.
  • According to one analysis of 37 studies, however, research supports the general conclusion that massage therapy is effective. The studies included in the analysis suggest that a single session of massage therapy can reduce “state anxiety” (a reaction to a particular situation), blood pressure, and heart rate, and multiple sessions can reduce “trait anxiety” (general anxiety-proneness), depression, and pain.

Side Effects and Cautions

Massage therapy appears to have few serious risks—if it is performed by a properly trained therapist and if appropriate cautions are followed. The number of serious injuries reported is very small. Side effects of massage therapy may include temporary pain or discomfort, bruising, swelling, and a sensitivity or allergy to massage oils.

General cautions about massage therapy include the following:

  • Vigorous massage should be avoided by people with bleeding disorders or low blood platelet counts, and by people taking blood-thinning medications such as warfarin.
  • Massage should not be done in any area of the body with blood clots, fractures, open or healing wounds, skin infections, or weakened bones (such as from osteoporosis or cancer), or where there has been a recent surgery.
  • Although massage therapy appears to be generally safe for cancer patients, they should consult their oncologist before having a massage that involves deep or intense pressure. Any direct pressure over a tumor usually is discouraged. Cancer patients should discuss any concerns about massage therapy with their oncologist.
  • Pregnant women should consult their health care provider before using massage therapy.

Relaxation Techniques

Scientific Evidence

  • In 2008, a major review of the evidence for relaxation in the treatment of depression found that relaxation techniques were more effective than no treatment for depression, but not as effective as cognitive-behavioral therapy.

Side Effects and Cautions

  • Relaxation techniques are generally considered safe for healthy people. There have been rare reports that certain relaxation techniques might cause or worsen symptoms in people with epilepsy or certain psychiatric conditions, or with a history of abuse or trauma. People with heart disease should talk to their doctor before doing progressive muscle relaxation.
  • Relaxation techniques are often used as part of a treatment plan and not as the sole treatment for potentially serious health conditions.


Scientific Evidence

  • Research suggests that yoga might help with conditions such as anxiety, depression, and insomnia. However, more well-designed studies are needed before definitive conclusions can be drawn about yoga’s use for specific health conditions.

Side Effects and Cautions

  • Yoga is generally considered to be safe in healthy people when practiced appropriately. Studies have found it to be well tolerated, with few side effects.
  • People with certain medical conditions should not use some yoga practices. For example, people with disc disease of the spine, extremely high or low blood pressure, glaucoma, retinal detachment, fragile or atherosclerotic arteries, a risk of blood clots, ear problems, severe osteoporosis, or cervical spondylitis should avoid some inverted poses.
  • Although yoga during pregnancy is safe if practiced under expert guidance, pregnant women should avoid certain poses that may be problematic.

NCCAM Clinical Digest is a service of the National Center for Complementary and Alternative Medicine, NIH, DHHS. NCCAM Clinical Digest, a monthly e-newsletter, offers evidence-based information on CAM, including scientific literature searches, summaries of NCCAM-funded research, fact sheets for patients, and more.

The National Center for Complementary and Alternative Medicine is dedicated to exploring complementary and alternative healing practices in the context of rigorous science, training CAM researchers, and disseminating authoritative information to the public and professionals. For additional information, call NCCAM's Clearinghouse toll-free at 1-888-644-6226, or visit the NCCAM Web site at NCCAM 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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