Healthy and Green Living

Our natural body rhythms are synchronized by the changing light of
the sun at dawn and dusk, and we need 20 minutes of natural
light every single day to keep our natural rhythms in working order.

Very few of us get more than a few snatches of outdoor light
(unimpeded by windows and glasses) in the winter months. Just
looking at the amount of winter outdoor time my normal, very
active extended family averages astonished and appalled me,
since it was so minimal. I expect my family’s exposure to light
is quite typical. Worse, we all exhibit some of the symptoms of
natural light deficiency.

Do you exhibit outdoor light deficiency? Take this quiz to find out:

1. Do your eyes receive 15 to 20 minutes of full-spectrum light without UV blocking glasses every day?
2. Does your skin receive 15 to 20 minutes of full-spectrum light without sunscreen every day?
3. Do you suffer from any sleep disorders?
4. If you don’t get 20 minutes of natural light a day, do you supplement vitamin D?
5. Do you always put sunscreen on when you go outdoors?
6. Do you wear UV–blocking sunglasses?
7. Do you wear UV–blocking glasses?
8. Do you believe that bright light is bad for you?
9. Are you frequently groggy?
10. If you are elderly you need five times more natural light to regulate the Circadian Rhythm than younger people. Do you receive enough?

Do you have Seasonal Affective Disorder?
Are you hyperactive, or are your children?
Do you feel stress?
Are you overweight and crave carbohydrates?
Do you get sick frequently?
Are you sensitive to chemicals and feel it is hard for you to detox?
Do you spend time with cool white artificial light?
Is your cholesterol high?
Do you have psoriasis?
Is your sex drive low?

Here are some salient facts about natural light and why we need it, although all of the symptoms listed in the quiz can reflect deficiency in natural light.

• Forty percent of the population is considered deficient in Vitamin D. Our bodies (most importantly our eyes), need fifteen to twenty minutes of exposure to the full-spectrum sunlight without sunscreens or UV blocking glasses every day in order for the skin to manufacture vitamin D!
• Most sunscreens only protect against UVB, and overuse of UVB sunscreen can interfere with vitamin D manufacture. Glasses and windows also interfere with absorbing full-spectrum sunlight.
• The light brightness measurement is called a lux. For therapeutic reasons you need to be exposed to light that is at least as bright as dawn or twilight, of 2,500–10,000 lux, even on cloudy days. Regular incandescent light bulbs don’t even get close, producing 500-1,000 lux on the work surface!
• When natural light is absorbed by the retina of the eye, electrical impulses are carried along the optic nerve to the brain and the hypothalamus, pineal gland, and pituitary gland, where it is used by the body to activate neurotransmitters that turn on many hormonal systems, including the metabolism, reproductive functions, and the internal biological clock called the Circadian Rhythm.
• The Circadian Rhythm of the body is activated by light that is significantly brighter and more complex in spectrum than that which is needed for visual work. NASA installs full-spectrum lighting in space craft for this reason.
• Light exposure raises seratonin, which keeps you awake and alert.
• Melatonin rises in the dark, which makes you sleepy. It is suppressed by daylight. If you don’t get enough light of sufficient intensity (lux) you produce too much melatonin, which makes you groggy. (If you are tired during the day, you might go out and get some sun!)

What to Do
Bathe your eyes in natural outdoor light without any glasses for up to 20 minutes every day. Soak it up in a walk, on a deck, in a lawn chair, at the beach. Through your eyes, light goes directly to the hypothalamus, and from there to every cell in your body—and it helps your skin manufacture Vitamin D, an essential nutrient (see above, for more).

• Take your lunch break outdoors whenever you can. You don’t need to be in the direct sun. A porch is fine!
• Take the opportunity to read the daily newspaper in the sun; look at your mail there, too.
• In the winter, walk somewhere that isn’t icy, so that you stay warm.
• If you are disabled, infirm, or unable to get outside for whatever reason, including living in a city, sit by an open window for 20 minutes or so every day, if it isn’t too cold.
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