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Health Condition

Seasonal Affective Disorder

  • L-Tryptophan

    Some research suggests that L-tryptophan alone or in combination with light therapy may improve SAD symptoms.

    Dose:

    With doctor's supervision, 2 to 4 grams per day, increasing up to 6 grams if no improvement
    L-Tryptophan
    ×
    Since disturbances of serotonin metabolism may be part of the cause of SAD,1 and creating a deficiency of L-tryptophan, a precursor of serotonin, worsens symptoms of SAD,2 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.3 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.4 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.5 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.65-HTP (5-hydroxytryptophan) is a substance related to L-tryptophan that also increases serotonin production and has shown antidepressant activity.7 It may also be useful in the treatment of SAD, but there is currently no research testing this possibility.

  • St. John’s Wort

    St. John’s wort, an herb well known for its antidepressant activity, may improve SAD symptoms.

    Dose:

    Consult a qualified healthcare practitioner
    St. John’s Wort
    ×

    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.8 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,9 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.10 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.11 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.

  • Vitamin D

    Supplementing with vitamin D may improve SAD in people with low levels of the vitamin.

    Dose:

    Refer to label instructions
    Vitamin D
    ×

    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.12

    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.13 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.14 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.

  • 5-HTP

    The supplement 5-Hydroxytryptophan increases serotonin production and has shown antidepressant activity. It may be useful in the treatment of SAD.

    Dose:

    900 mg a day of a standardized extract
    5-HTP
    ×
     

    5-HTP is a substance that increases serotonin production and has shown antidepressant activity.15 It may also be useful in the treatment of SAD, but there is currently no research testing this possibility.

What Are Star Ratings
×
Reliable and relatively consistent scientific data showing a substantial health benefit.
Contradictory, insufficient, or preliminary studies suggesting a health benefit or minimal health benefit.
For an herb, supported by traditional use but minimal or no scientific evidence. For a supplement, little scientific support.

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.16,17,18,19 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%.18 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.17 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.22 Light therapy begun prior to the onset of winter depression appears to have a preventive effect in people susceptible to SAD.23

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.16 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.25

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.26

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.19

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.28 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.29

References

1. Neumeister A, Konstantinidis A, Praschak-Rieder N, et al. Monoaminergic function in the pathogenesis of seasonal affective disorder. Int J Neuropsychopharmacol 2001;4:409-20.

2. Van der Does AJ. The effects of tryptophan depletion on mood and psychiatric symptoms. J Affect Disord 2001;64:107-19.

3. Levitt AJ, Brown GM, Kennedy SH, Stern K. Tryptophan treatment and melatonin response in a patient with seasonal affective disorder. J Clin Psychopharmacol 1991;11:74-5.

4. Lam RW, Levitan RD, Tam EM, et al. L-tryptophan augmentation of light therapy in patients with seasonal affective disorder. Can J Psychiatry 1997;42:303-6.

5. Ghadirian AM, Murphy BE, Gendron MJ. Efficacy of light versus tryptophan therapy in seasonal affective disorder. J Affect Disord 1998;50:23-7.

6. McGrath RE, Buckwald B, Resnick EV. The effect of L-tryptophan on seasonal affective disorder. J Clin Psychiatry 1990;51:162-3.

7. Birdsall TC. 5-Hydroxytryptophan: a clinically-effective serotonin precursor. Alternative Med Rev 1998;3:271-80.

8. Markowitz JS, Donovan JL, DeVane CL, et al. Effect of St John's wort on drug metabolism by induction of cytochrome P450 3A4 enzyme. JAMA 2003;290:1500-4.

9. Kim HL, Streltzer J, Goebert D. St. John's wort for depression: a meta-analysis of well-defined clinical trials. J Nerv Ment Dis 1999;187:532-8 [review].

10. Martinez B, Kasper S, Ruhrmann S, Moller HJ. Hypericum in the treatment of seasonal affective disorders. J Geriatr Psychiatry Neurol 1994;7:S29-33.

11. Wheatley D. Hypericum in seasonal affective disorder (SAD). Curr Med Res Opin 1999;15:33-7.

12. Stumpf WE, Privette TH. Light, vitamin D and psychiatry. Role of 1,25 dihydroxyvitamin D3 (soltriol) in etiology and therapy of seasonal affective disorder and other mental processes. Psychopharmacology (Berl) 1989;97:285-94 [review].

13. Gloth FM III, Alam W, Hollis B. Vitamin D vs broad spectrum phototherapy in the treatment of seasonal affective disorder. J Nutr Health Aging 1999;3:5-7.

14. Frandsen TB, Pareek M, Hansen JP, Nielsen CT. Vitamin D supplementation for treatment of seasonal affective symptoms in healthcare professionals: a double-blind randomised placebo-controlled trial. BMC Res Notes 2014;7:528.

15. Birdsall TC. 5-Hydroxytryptophan: a clinically-effective serotonin precursor. Alternative Med Rev 1998;3:271-80.

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

17. 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.

18. 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.

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

20. 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.

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

22. 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].

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

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

25. 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.

26. Krauchi K, Reich S, Wirz-Justice A. Eating style in seasonal affective disorder: who will gain weight in winter? Compr Psychiatry 1997;38:80-7.

27. Krauchi K, Keller U, Leonhardt G, et al. Accelerated post-glucose glycaemia and altered alliesthesia-test in Seasonal Affective Disorder. J Affect Disord 1999;53:23-6.

28. Danilenko KV, Putilov AA, Russkikh GS, et al. Diurnal and seasonal variations of melatonin and serotonin in women with seasonal affective disorder. Arctic Med Res 1994;53:137-45.

29. Blum I, Vered Y, Graff E, et al. The influence of meal composition on plasma serotonin and norepinephrine concentrations. Metabolism 1992;41:137-40.

30. Christensen L. Effects of eating behavior on mood: a review of the literature. Int J Eat Disord 1993;14:171-83 [review].

31. 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.

32. 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.

33. 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.

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The information presented by TraceGains is for informational purposes only. It is based on scientific studies (human, animal, or in vitro), clinical experience, or traditional usage as cited in each article. The results reported may not necessarily occur in all individuals. Self-treatment is not recommended for life-threatening conditions that require medical treatment under a doctor's care. For many of the conditions discussed, treatment with prescription or over the counter medication is also available. Consult your doctor, practitioner, and/or pharmacist for any health problem and before using any supplements or before making any changes in prescribed medications. Information expires December 2025.