Some recent studies have indicated a possible correlation between light at night and breast cancer. Breast cancer is 5 times more common in industrialized nations than it is in underdeveloped countries. Blind women have a lower-than- average breast cancer rate.

While still a hypothesis, it is believed that light interferes with the production of melatonin, a tumor suppressing hormone, in the brain. Melatonin is produced at night and its levels drop in the presence of light. One study by the University of Haifa in Israel overlaid satellite images of the Earth onto cancer registries. Their findings indicate that this is a correlation that should be considered.

What can be done about this in our homes? While I don’t think it is necessary to stumble around in the dark every night there are some easy things that we can do. The main thing would be to limit your exposure to bright light at least 3 hours before going to bed. Limit your computer time to around 15 minutes at night. Get curtain for your windows so that streetlight and/or your neighbors lights does not enter your rooms. Use night lights in your bathroom for those late night visits. It has even been suggested to use red lightbulbs, as their low wavelengths is thought to minimally affect melatonin production. How about utilizing motion detectors on the outside of your home? Your home would still be provided security and you would be saving energy since your lights would be shining only when needed. Most importantly, your sleep and your neighbors’ would not be interrupted by unnecessary light. Checkout Light Pollution And Your Health for more information.