By Marc Sorenson,, EdD. Sunlight Institute…
The medical properties are terrific! A new study from the University of Kansas demonstrates that children born to women who receive more sun exposure during the second trimester of pregnancy, have a considerably lowered risk of asthma later in life. The researchers did not look at sunny geographical areas vs. areas of little sun to make their assessments, but rather looked at different amounts of sunlight occurring in the same areas in different years. They found that in areas that had experienced high quantities of sun in a given year, the risk of asthmatic children being born in that year was reduced, that is, if their mothers experienced that sun exposure during the second trimester of pregnancy.
The researchers theorized that higher levels of vitamin D during sunny times accounted for the protective effects of sunlight. That may be true, but the protection may have occurred from sun exposure per se, independent of vitamin D. One of the most recent studies on factors that contribute to asthma showed that living in a room without windows was associated with an increased the risk of asthma of 930%, and living in an area without adequate sun was associated with an increased the risk of 220%. Considering that windows filter out the UVB light that stimulates the production of vitamin D, having windows could not have reduced asthma by vitamin D production—it had to be some other factor—something that entered the room through that window glass–protected the people with windows from the remarkable increase in asthma they would have otherwise had. We know that UVA light, which does pass through windows, stimulates the production of nitric oxide, which is a potent vasodilator. Could it also be a bronchodilator? This explanation, of course, is theory.
Whatever the reason, the study on sunlight and pregnancy is just one of many that have indicated a protective effect of sun exposure against asthma. Safely embrace the sun, and tell pregnant mothers to do the same. It could enhance the quality of life for their children later on, and reduce the cost of health care for all of us.
 Kamran A, Hanif S, Murtaza G. Risk factors of childhood asthma in children attending Lyari General Hospital. J Pak Med Assoc 2015 Jun;65(6):647-50.