Late Night Exposure to Light May Cause Depression

A new study from Ohio State University found that hamsters that were repeatedly exposed to low levels of light at night developed depressive symptoms after only a few weeks. Some of these symptoms included sluggishness and reduced physical activity, greater than normal distress from being placed in water, and reduced interest in sugar water, a favorite hamster treat. There were even changes in the hippocampus area of the brain that were very similar to the changes in human brains that have been observed in people suffering from depression.
This suggests that exposure to low levels of lighting at night, such as a night light, television screen, or computer monitor, might also trigger depression in humans.
Mood disorders are by no means the only health condition linked to artificial lighting and screen time at night. Earlier this year, the American Medical Association (AMA) put out a disturbing summary of adverse health effects from nighttime lighting, noting that artificial lights disrupt circadian rhythms and alter the body’s normal hormonal responses. In particular, when people spend too little time in darkness, it seems that the body suppresses release of the hormone melatonin, which — among other things — is thought to fight tumor growth and cancers. Other health conditions affected by changes in circadian rhythms, according to the AMA report, may include obesity, diabetes and reproductive problems.
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Lisa Birnesser - July 29, 2012
Very interesting information, Carol. I hadn’t read this article yet. Thanks for sharing!
Gretchen Pritts - July 30, 2012
Interesting article on late night light exposure. I’m not sure about it causing depression, but I know that it affects my sleep patterns. I really do try to turn off all electronics 30 minutes prior to sleep. Thanks for sharing.