Summary
For me light therapy is very helpful for SAD symptoms, but the effective "dosage" and timing has changed over the years.
I’ve mentioned this in passing a few times on the site — the exposure length and timing of the bright light therapy I use to control carb cravings, insomnia, low mood, and zombie brain changes over the years. I used to need it only from October to April, for 30 minutes, and it wouldn’t work after 9 am. Then I switched to 60 minutes for quite a while, until it started to make me antsy. Now I’m down to 20 minutes, it won’t work after 7:15 am, and I seem to need it all year. I consider this further proof that some chicks are not meant to live further north than a palm tree.
Here are a few references I’ve used to figure out timing and “dosage.”
- Chronotherapeutics for Affective Disorders: A Clinician’s Manual for Light and Wake Therapy
- Circadian rhythm questionnaire by Philips, a light therapy device manufacturer
- Light therapy online info guide
Other interesting info:
- Light therapy has different effects on younger and older eyes (New York Times article)
- According to this light therapy retail website, “Some drugs make patients photosensitive, as can contact lenses, and those patients may need to be conservative when starting light therapy.”
When this content was published
This content was first posted in May 2013 and updated in April 2023.
Illustration: Remix by MRhea.