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    Seasonal Affective Disorder (Holistic)

    Seasonal Affective Disorder (Holistic)

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    About This Condition

    A cold and dark winter can trigger depression in people who suffer from SAD. According to research or other evidence, the following self-care steps may be helpful.
    • Add more D to your diet

      See a qualified health practitioner to find out if you are low in vitamin D, and if you should take large amounts under medical supervision to help improve mood and well-being

    • Soak in the sun

      Spend more time outdoors to help improve the regulation of important brain chemicals that affect mood

    • Try light therapy

      Reduce symptoms by using a full-spectrum fluorescent light during dark mornings or evenings

    • Check out St. John's wort

      This well-known herbal remedy may improve mild to moderate depression; take 900 mg a day of a standardized extract

    • Work in a workout

      Get an hour of aerobic or anaerobic exercise three times a week in bright light to improve mood


    About This Condition

    Seasonal affective disorder (SAD) is an extreme form of common seasonal mood cycles, in which depression develops during the winter months.

    How seasonal changes cause depression is unknown, but most of the research into mechanisms and treatment has focused on changes in levels of the brain chemicals melatonin and serotonin in response to changing exposure to light and darkness.


    SAD is characterized by typical symptoms of depression , such as sadness, hopelessness, and thoughts of suicide (in some cases), and "atypical" depressive symptoms such as excessive sleep, lethargy, carbohydrate cravings, overeating, and weight gain . The symptoms usually occur the same time of year, typically fall and winter, and disappear with the onset of spring and summer.

    Light exposure research and treatment measures in "lux" units. For example, the intensity of light on a high mountain at the equator at midday is greater than 100,000 lux, compared with less than 11 lux generated by a moonlit night. A well-lit kitchen or office may be around 500 lux.

    Healthy Lifestyle Tips

    Exercise can ease depression and improve well being, in some cases as effectively as antidepressant medications.1 One study found that both one hour of aerobic exercise three times per week and the same amount of anaerobic exercise were significantly and equally effective in reducing symptoms of depression.2 In a preliminary study of women with SAD, exercise while exposed to light was more likely to be associated with fewer seasonal depressive symptoms than was exercise performed with little light exposure.3 A controlled study of 120 indoor employees used relaxation training as the placebo in a study of fitness training, light exposure, and winter depressive symptoms. Fitness training was performed two to three times per week while exposed to either bright light (2,500-4,000 lux) or ordinary light (400-600 lux). Compared to relaxation, exercise in bright light improved general mental health, social functioning, depressive symptoms, and vitality, while exercise in ordinary light improved vitality only.

    Holistic Options

    Diminished sunlight exposure in winter contributes to changes in brain chemistry and plays a role in seasonal mood changes. Artificial lights have been widely used to increase light exposure during winter months. Many studies show the benefit of light therapy in the treatment of SAD.4 , 5 , 6 , 7 In a controlled trial, 96 patients with SAD were treated with light at 6,000 lux for 1.5 hours in either morning or evening, or with a sham negative ion generator, which was used as the placebo. After three weeks of treatment, morning light produced complete or near-complete remission for 61% of patients, while evening light helped 50%, and placebo helped 32%.8 Another study similarly found morning light to have more antidepressant activity than evening light for people with SAD. This study also found that patterns of melatonin production were altered in seasonal depression, and that morning light therapy shifted this pattern toward those of control subjects who did not have seasonal depression.9 Blood flow to certain regions of the brain was measured after light therapy and was increased in seasonal depression patients who benefited from the light therapy. The increase in regional brain blood flow did not occur in those patients who did not respond to the light therapy.10 Light therapy begun prior to the onset of winter depression appears to have a preventive effect in people susceptible to SAD.11

    A review of clinical trials of light therapy for SAD concluded that the intensity of the light is related to the effectiveness of the treatmnent.12 A higher response rate was seen in trials where light intensity was greater, compared with trials that used light therapy of lower intensity. Red and potentially harmful ultraviolet wavelengths are not necessary for a response to light therapy.13

    A study of the adverse side effects from high-intensity light therapy found them to be common, mild and brief. Among people who underwent brief treatment with 10,000 lux, 45% experienced side effects such as headaches and eye and vision changes. Described as mild and temporary, they did not interfere with treatment.14

    Dawn simulation is a form of light therapy involving gradually increasing bedside light in the morning. In a comparison study, dawn simulation using 100-300 lux for 60-90 minutes every morning improved symptoms of SAD similarly to bright light therapy using 1,500-2,500 lux for two hours every morning.15

    A negative ionizer is a device that emits negatively charged particles into the air. Negative air ionization may be useful in treating SAD. One double-blind trial compared the benefits of high-density negative ionization, providing 2.7 million ions per cubic centimeter, and low-density negative ionization, providing 10,000 ions per cubic centimeter, for people with SAD. Atypical depressive symptoms improved by 50% or more for 58% of patients receiving the high-density ionization for 30 minutes daily, while only 15% of those receiving low-density ionization had 50% or greater improvement. There were no side effects, and all of the patients who responded to the therapy relapsed when ionization was discontinued.16 In another controlled trial, high-density ionization was found equally as effective as light therapy, and both were significantly more effective than low-density ionization.17

    Eating Right

    The right diet is the key to managing many diseases and to improving general quality of life. For this condition, scientific research has found benefit in the following healthy eating tips.

    Recommendation Why
    Choose complex carbs
    Replacing simple carbohydrates, such as sweets and processed foods made with white flours, with unrefined, whole grain options may help achieve long-term control over negative mood.

    Cravings for simple carbohydrates are increased in SAD, and women diagnosed with this form of winter depression have been found to eat more carbohydrates, both sweets and starches, than do healthy women. These women also report eating in response to emotionally difficult conditions, anxiety , depression, and loneliness more frequently than healthy women, but eating patterns associated with SAD are distinct from those of women with eating disorders .

    People with SAD process sugar differently in winter compared with summer or after light therapy in winter. Changes in neurotransmitters that may affect cravings also occur in women with SAD. Because consumption of carbohydrates can influence neurotransmitter levels, some authorities have speculated that eating simple carbohydrates may be a form of self-medication in people with SAD. A review of the research on diet and mood found that, while eating simple carbohydrates in reaction to depressed mood does bring about a temporary lift in mood, other evidence suggests that long-term control of negative moods is, for some people, best achieved by eliminating simple carbohydrates from the diet. No research has yet been conducted, however, to evaluate the benefits of a diet low in simple carbohydrates (or any other dietary intervention) for people with SAD.


    What Are Star Ratings?

    Our proprietary "Star-Rating" system was developed to help you easily understand the amount of scientific support behind each supplement in relation to a specific health condition. While there is no way to predict whether a vitamin, mineral, or herb will successfully treat or prevent associated health conditions, our unique ratings tell you how well these supplements are understood by some in the medical community, and whether studies have found them to be effective for other people.

    For over a decade, our team has combed through thousands of research articles published in reputable journals. To help you make educated decisions, and to better understand controversial or confusing supplements, our medical experts have digested the science into these three easy-to-follow ratings. We hope this provides you with a helpful resource to make informed decisions towards your health and well-being.

    3 Stars Reliable and relatively consistent scientific data showing a substantial health benefit.

    2 Stars Contradictory, insufficient, or preliminary studies suggesting a health benefit or minimal health benefit.

    1 Star For an herb, supported by traditional use but minimal or no scientific evidence. For a supplement, little scientific support.

    Supplement Why
    2 Stars
    With doctor's supervision, 2 to 4 grams per day, increasing up to 6 grams if no improvement
    Some research suggests that L-tryptophan alone or in combination with light therapy may improve SAD symptoms.
    Since disturbances of serotonin metabolism may be part of the cause of SAD, and creating a deficiency of L-tryptophan, a precursor of serotonin, worsens symptoms of SAD, L-tryptophan supplementation might be helpful. One case report describes a patient with SAD who improved after taking L-tryptophan daily, 1 gram with dinner and 1 gram at bedtime. In a small, preliminary study, people with SAD who responded poorly or not at all to bright light therapy were given 3 grams per day of L-tryptophan for two weeks, in addition to light therapy. Nine of 14 people responded well to this combination. Another small preliminary study found that one of five SAD patients that did not respond to light therapy did improve after L-tryptophan supplementation in the amount of 4 grams per day, increased to 6 grams per day if no improvement occurred at the lower dose. A small controlled trial found that a combination of 1.5 grams of L-tryptophan, 50 mg of vitamin B6, 300 mg vitamin C, and eight ounces of fruit juice, taken three times daily, was more effective for reducing symptoms of SAD than the same combination without L-tryptophan. 5-HTP (5-hydroxytryptophan) is a substance related to L-tryptophan that also increases serotonin production and has shown antidepressant activity. It may also be useful in the treatment of SAD, but there is currently no research testing this possibility.
    2 Stars
    St. John's Wort
    Consult a qualified healthcare practitioner
    St. John's wort, an herb well known for its antidepressant activity, may improve SAD symptoms.

    Caution: It is likely that there are many drug interactions with St. John's wort that have not yet been identified. St. John's wort stimulates a drug-metabolizing enzyme (cytochrome P450 3A4) that metabolizes at least 50% of the drugs on the market. Therefore, it could potentially cause a number of drug interactions that have not yet been reported. People taking any medication should consult with a doctor or pharmacist before taking St. John's wort. 

    St. John's wort , an herb well known for its antidepressant activity, has been examined for its effectiveness in treating SAD. In a preliminary trial, patients with seasonal depression were given 900 mg per day of St. John's wort in addition to either bright light (3,000 lux for two hours) or a dim light (300 lux for two hours) placebo. Both groups had significant improvement in depressive symptoms, but there was no difference between the groups. The authors concluded that St. John's wort was beneficial with or without bright light therapy , but a placebo effect from the herb cannot be ruled out in this study. Another preliminary study asked 301 SAD patients to report the changes in their symptoms resulting from the use of St. John's wort at 300 mg three times daily. Significant overall improvement was reported by these patients. Some of the subjects used light therapy in addition to St. John's wort. They reported more improvement in sleep, but overall improvement was not significantly different from those using St. John's wort alone. Double-blind research is needed to confirm the usefulness of St. John's wort for treating SAD.

    2 Stars
    Vitamin D
    Refer to label instructions
    Supplementing with vitamin D may improve SAD in people with low levels of the vitamin.

    Vitamin D is well known for its effects on helping to maintain normal calcium levels, but it also exerts influence on the brain, spinal cord, and hormone-producing tissues of the body that may be important in the regulation of mood.

    In one study, people with SAD were randomly assigned to receive either 100,000 IU of vitamin D one time only or two hours of bright-light therapy every day for one month. After one month, researchers observed a significant improvement in depression in the group that received vitamin D, but not in the group given light therapy. However, another double-blind study found that supplementation with 2,800 IU per day of vitamin D during the winter was not beneficial for people with SAD. Most of the participants in the study in which vitamin D was beneficial were deficient in vitamin D, whereas most of the participants in the negative study were not deficient. While additional research needs to be done, current evidence suggests that vitamin D supplementation may improve SAD in people with vitamin D deficiency but not in people without vitamin D deficiency.

    1 Star
    900 mg a day of a standardized extract
    The supplement 5-Hydroxytryptophan increases serotonin production and has shown antidepressant activity. It may be useful in the treatment of SAD.

    5-HTP is a substance that increases serotonin production and has shown antidepressant activity. It may also be useful in the treatment of SAD, but there is currently no research testing this possibility.


    1. Blumenthal JA, Babyak MA, Moore KA, et al. Effects of exercise training on older patients with major depression. Arch Intern Med 1999;159:2349-56.

    2. Martinsen EW, Hoffart A, Solberg O. Comparing aerobic with nonaerobic forms of exercise in the treatment of clinical depression: a randomized trial. Compr Psychiatry 1989;30:324-31.

    3. Groom KN, O'Connor ME. Relation of light and exercise to seasonal depressive symptoms: preliminary development of a scale. Percept Mot Skills 1996;83:379-83.

    4. Lee TM, Chan CC. Dose-response relationship of phototherapy for seasonal affective disorder: a meta-analysis. Acta Psychiatr Scand 1999;99:315-23 [review].

    5. Lewy AJ, Bauer VK, Cutler NL, et al. Morning vs evening light treatment of patients with winter depression. Arch Gen Psychiatry 1998;55:890-6.

    6. Eastman CI, Young MA, Fogg LF, et al. Bright light treatment of winter depression: a placebo-controlled trial. Arch Gen Psychiatry 1998;55:883-9.

    7. Lingjaerde O, Foreland AR, Dankertsen J. Dawn simulation vs. lightbox treatment in winter depression: a comparative study. Acta Psychiatr Scand 1998;98:73-80.

    8. Eastman CI, Young MA, Fogg LF, et al. Bright light treatment of winter depression: a placebo-controlled trial. Arch Gen Psychiatry 1998;55:883-9.

    9. Lewy AJ, Bauer VK, Cutler NL, et al. Morning vs evening light treatment of patients with winter depression. Arch Gen Psychiatry 1998;55:890-6.

    10. Vasile RG, Sachs G, Anderson JL, et al. Changes in regional cerebral blood flow following light treatment for seasonal affective disorder: responders versus nonresponders. Biol Psychiatry 1997;42:1000-5.

    11. Partonen T, Lonnqvist J. Prevention of winter seasonal affective disorder by bright-light treatment. Psychol Med 1996;26:1075-80.

    12. Lee TM, Chan CC. Dose-response relationship of phototherapy for seasonal affective disorder: a meta-analysis. Acta Psychiatr Scand 1999;99:315-23 [review].

    13. Lee TM, Chan CC, Paterson JG, et al. Spectral properties of phototherapy for seasonal affective disorder: a meta-analysis. Acta Psychiatr Scand 1997;96:117-21 [review].

    14. Kogan AO, Guilford PM. Side effects of short-term 10,000-lux light therapy. Am J Psychiatry 1998;155:293-4.

    15. Lingjaerde O, Foreland AR, Dankertsen J. Dawn simulation vs. lightbox treatment in winter depression: a comparative study. Acta Psychiatr Scand 1998;98:73-80.

    16. Terman M, Terman JS. Treatment of seasonal affective disorder with a high-output negative ionizer. J Altern Complement Med 1995;1:87-92.

    17. Terman M, Terman JS, Ross DC. A controlled trial of timed bright light and negative air ionization for treatment of winter depression. Arch Gen Psychiatry 1998;55:875-82.

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