Seasonal-Affective-Disorder Explained

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.

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

Seasonal Affective Disorder

Health Condition