A couple of studies. Taken together, it sounds like you'd want lots of natural light and exercise:
Levitt AJ. Lam RW. Levitan R.
Title
A comparison of open treatment of seasonal major and minor depression with light therapy.
Source
Journal of Affective Disorders. 71(1-3):243-8, 2002 Sep.
Abstract
BACKGROUND: Although several investigators have described a milder form of seasonal affective disorder (SAD), called subsyndromal SAD, little is known about the effect of light therapy in this group. The current study evaluates 3 weeks of open treatment with light therapy in SAD and subsyndromal SAD patients. METHODS: Subjects with major or minor depression according to DSM-IV with a seasonal pattern were recruited during the winter of 1998-1999 from clinic patients and media advertising. Subjects were commenced on open treatment of morning light therapy, for 30 min daily using a new fluorescent light therapy unit that produced approximately 5,000 lux at a distance of 12 inches. The treatment lasted 3 weeks and at the end of the first and second week of treatment the duration of exposure could be increased to a maximum of 60 min at the discretion of the clinician. The Structured Interview Guide for the Hamilton Depression Rating Scale-SAD version (SIGH-SAD) was administered weekly to evaluate outcome. Response was defined in a variety of ways to reflect the fact that subsyndromal SAD subjects had milder symptoms. RESULTS: Forty-six subjects entered treatment and 44 (SAD, n = 29, subsyndromal SAD, n = 15) completed at least 2 weeks. Response rates were generally similar in SAD subjects (64-69%) and subsyndromal SAD (40-67%) patients. There was a trend for longer exposure to be associated with better outcome. CONCLUSIONS: Light therapy may be an effective treatment for subjects with both major and minor depression with a seasonal pattern. Optimal duration, for the light therapy unit used in this study, is likely 45-60 min daily.
Leppamaki SJ. Partonen TT. Hurme J. Haukka JK. Lonnqvist JK.
Title
Randomized trial of the efficacy of bright-light exposure and aerobic exercise on depressive symptoms and serum lipids.
Source
Journal of Clinical Psychiatry. 63(4):316-21, 2002 Apr.
Abstract
BACKGROUND: Season-related subsyndromal depressive symptoms during winter are common among populations at high latitudes. Both physical exercise and exposure to bright light can relieve the fatigue and downturn of mood associated with the shortening length of day. Serum cholesterol level may be related
to changes in mood, but the evidence is contradictory. Our objective was to compare the effect of aerobic exercise with or without bright-light exposure on health-related quality of life, mood, and serum lipids in a sample of relatively healthy adult subjects. METHOD: A randomized controlled trial was conducted with subjects allocated to group aerobics training in a gym with bright light (2500-4000 lux) (N = 40) or normal illumination (N = 42) or to relaxation/stretching sessions in bright light as a control group (N = 42) twice a week for a period of 8 weeks. Changes in mood were recorded using questionnaires at the beginning of the study, at weeks 4 and 8. and at follow-up 4 months after the study. A blood sample was drawn before and after the 8-week intervention to measure the concentrations of serum lipids. RESULTS: Ninety-eight subjects completed the 8-week study. Both exercise and bright light effectively relieved depressive symptoms. Bright light reduced atypical depressive symptoms more than exercise (p = .03), based on the atypical symptoms subscore of the Structured Interview Guide for the Hamilton Depression Rating Scale-Seasonal Affective Disorders Version Self-Rating Format. There were no significant differences between the study groups in the changes in serum lipid levels. CONCLUSION: Bright light administered twice a week, alone or combined with physical exercise, seems to be a useful intervention for relieving seasonal mood slumps.
Avery DH. Eder DN. Bolte MA. Hellekson CJ. Dunner DL. Vitiello MV. Prinz PN.
Title
Dawn simulation and bright light in the treatment of SAD: a controlled study.
Source
Biological Psychiatry. 50(3):205-16, 2001 Aug 1.
Abstract
BACKGROUND: Some small controlled studies have found that dawn simulation is effective in treating seasonal affective disorder (SAD). With a larger sample size and a longer duration of treatment, we compared dawn simulation with bright light therapy and a placebo condition in patients with SAD. METHOD: Medication-free patients with SAD were randomly assigned to one of three conditions: bright light therapy (10,000 lux for 30 min, from 6:00 AM to 6:30 AM), dawn simulation (1.5 hour dawn signal from 4:30 AM to 6:00 AM peaking at 250 lux), and a placebo condition, a dim red light (1.5 hour dawn signal from 4:30 am to 6:00 AM peaking at 0.5 lux.) Over the subsequent 6 weeks, the subjects were blindly rated by a psychiatrist using the Structured Interview Guide for the Hamilton Depression Rating-Seasonal Affective Disorder Version (SIGH-SAD). We modeled the profiles of the remissions (SIGH-SAD < or = 8) and response (> or =50% decrease in SIGH-SAD) to treatment over time using Cox proportional hazards models. RESULTS: The sample consisted of 95 subjects who were randomized to the three conditions: bright light (n = 33), dawn simulation (n = 31) and placebo (n = 31). Dawn simulation was associated with greater remission (p <.05) and response (p <.001) rates compared to the placebo. Bright light did not differ significantly from the placebo. Dawn simulation was associated with greater remission (p <.01) and response (p <.001) rates compared to the bright light therapy. The mean daily hours of sunshine during the week before each visit were associated with a significant increase in likelihood of both remission (p <.001) and response (p <.001). CONCLUSIONS: Dawn simulation was associated with greater remission and response rates compared to the placebo and compared to bright light therapy. The hours of sunshine during the week before each assessment were associated with a positive clinical response.
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