Light Pollution and Your Health

Light from the TV at night may be harmful to your health.
(Photo © istockphoto/joshblake)

My amazingly talented friend Amy was recently interviewed on a Denver radio station for a story she wrote about the link between light pollution and cancer.

According to Amy, science shows that “Humans, as well as many animals and plants, need regular exposure to darkness to maintain what’s called the circadian rhythm—essentially the body’s internal clock, which governs various bodily functions.” She adds that, “In several studies conducted over the past decade, scientists have found that increased exposure to light at night correlates to higher cancer rates, particularly for those cancers like breast or prostate that require hormones to grow.” (Read Amy’s full article on GOOD, and listen to her radio interview. It starts at about 29:45.)

What I find most fascinating about the recent studies Amy talks about in her article is how closely they intersect with ancient Eastern medicine. In Traditional Chinese Medicine (TCM), for example, uninterrupted rest is essential for maintaining good blood and qi—two of the five vital substances that need to be in harmony for optimum health.

From 11 P.M. to 3 A.M., the blood goes into repair mode. According to TCM, the functions of the blood include providing nourishment and moisture to the body. It is also the material foundation of the mind, and resides within the yin, which has a relationship with all bodily fluids. In addition, the hours of 3 A.M. to 7 A.M.  are crucial for qi. Qi is our primary life force, and it not only gives us our vitality, but also the flow of qi helps bring nutrients to our tissues and boosts our immune function.

The connection: Exposure to light—from cell phones, computer screens, your TV, etc.—disrupts these natural cycles creating imbalances that make you more susceptible to disease-causing external pathogens. So it seems regardless of whether you take an Eastern or Western stance on your personal health, it’s important to turn the lights off at night, and embrace the dark.