By Marc Sorenson, EdD. Sunlight Institute…
I suppose that it’s asking a bit much to tell someone to be born in the right season. But if it were possible, it would probably help a person to avoid some allergies. A most interesting scientific study from Korea explored the relationship among birth season, sunlight exposure during infancy, and allergic disease. It came to some very intriguing conclusions that indicate that sun exposure during pregnancy, and during the first two years of life, is exceptionally important.  The researchers explored relationships between birth season, sunlight exposure, and several allergic diseases.
They introduced their research by stating that “The recent increase in the prevalence of allergic diseases is hypothetically attributed to immune dysregulation in turn caused by a reduction in exposure to sunlight.”
Here are their findings:
- The prevalence of atopic dermatitis, a skin allergy, was 24% higher in children born in winter than those born in summer.
- Birth in winter was associated with a 56% increase in the prevalence of food allergy (FA).
- In addition, the lifetime prevalence of allergic diseases except food allergy (FA) was higher in children who had experienced inadequate sunlight in the first two years of life, compared to those children who had adequate exposure. In those whose sunlight exposure was inadequate, the following increases in risk were noted:
- Asthma 40% increased risk
- Allergic rhinitis (AR) 40%
- Atopic dermatitis (AD) 26%
The researchers concluded that “Birth in winter may be associated with development of AD and FA. Inadequate sunlight exposure before the age of 24 months might possibly increase the risks of development of asthma, AR, and AD.”
Great research, and the results are what we would have expected. There is almost no limit to the disease-preventing power of the Sun.
 Hwang JM, Oh SH, Shin MY. The relationships among birth season, sunlight exposure during infancy, and allergic disease. Korean J Pediatr. 2016 May;59(5):218-25. doi: 10.3345/kjp.2016.59.5.218. Epub 2016 May 31.
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.
By Marc Sorenson, EdD, Sunlight Institute…
Asthma is a disorder characterized by inflammation of the air passages, which cause narrowing of the airways that transport air from the nose and mouth to the lungs.[i] The mechanism by which sunlight may reduce asthma and its symptoms could be the anti-inflammatory properties of the vitamin D production that it stimulates in the skin. Inflammation is often caused by proteins called cytokines that are either pro-inflammatory or anti-inflammatory elements of the immune system.[ii] Vitamin D has the ability to inhibit pro-inflammatory cytokine production while stimulating the production of anti-inflammatory cytokines.[iii] However, there are likely other attributes of sunlight, beyond stimulating vitamin D production in the skin, that have beneficial affects.
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 sunlight was associated with an increased the risk of 220%.[iv] 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.
Other research that indicates a direct influence of sunlight on asthma, is one by Hart and her colleagues, which showed that controlled exposure to ultraviolet light (UVR) in mice markedly limited the development, incidence and severity of asthma symptoms such as inflamed airways and lungs.[v] These researchers exposed mice to allergens that generally brought on asthma attacks and then exposed them to sun lamps for 30 minutes. After the exposure, the allergens caused no attacks. The researchers also stated that sunlamp exposure produced a cell type in mice, that when transferred into other mice, suppressed the immune reactions and halted symptoms. This is another indication that sunlight has a healthful effect on asthma beyond vitamin D production.
Dr. Litonjua and Dr. Weiss, noting that the prevalence of asthma and allergic diseases began to increase worldwide in 1960, hypothesized that since people have increasingly spent more time indoors, there has been less exposure to sunlight, which has led to decreased cutaneous vitamin D production.[vi] This could have further led to vitamin D deficiency in pregnant women, resulting in more asthma in their offspring. But was vitamin D deficiency the cause or was it simply sunlight deficiency? Or could it have been both?
At the health resort owned by the Sorensons, we often noticed that asthmatics ceased using their inhalers after a week or two of hiking in the sunshine. One of them decreased the dosage from 6 inhalers per day to zero in about a week. Could it have been sunlight? We believe that the combination of mostly plant-based nutrition, combined with sunlight, made the difference, and the aforementioned research provides reasonable support for that opinion.
[i] Asthma and Allergy Foundation of America: Asthma Facts and Figures. Accessed 3-6-2010 http://www.aafa.org/display.cfm?id=8&sub=42
[ii] Kurtzke J. On the fine structure of the distribution of multiple sclerosis 1,25-Dihydroxyvitamin D3 inhibits cytokine production by human blood monocytes at the post-transcriptional level. Cytokine 1992;4:506-12.
[iii] Canning MO, Grotenhuis K, de Wit H, Ruwhof C, Drexhage HA. I-alpha,25-Dihydroxyvitamin D3 (l,25(OH)(2)D(3)) hampers the maturation of fully active immature dendritic cells from monocytes. Eur J Endocrinol 2001;145:351-57.
[iv] 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.
[v] Hart, P. Exposure to sunlight could reduce asthma. Newsletter of the Telethon Institute for Child Health Research 2006;3:2
[vi] Litonjua AA, Weiss ST. Is vitamin D deficiency to blame for the asthma epidemic? J Allergy Clin Immunol 2007;120:1031-35.
By: Marc Sorenson, Sunlight Institute–
According to the Centers for Disease Control in May 2011, “about one in 12 people in the United States now has asthma—a total of 24.6 million people and an increase of 4.3 million since 2001.” This is another of those diseases like diabetes that is increasing out of control and shows no sign of abating.
The Scientific American, on April 14, 2011, published an article entitled Why are Asthma Rates soaring? In that article, they lamented the fact that for the last three decades asthma rates have been surging, and that differing theories have arisen as to the reason for the increase, only to be disproven and discarded. Among those theories was the hypothesis that the world has become so “clean” or sterile, that youngsters are not subjected to infectious organisms and thereby do not develop strong immune systems capable of fighting off pollens, dust, etc. To me, that seemed like a rather lame hypothesis, and the article indicates that the idea is no longer in vogue. Another theory was that those who had allergic reactions to various environmental pollutants had weaknesses that predisposed them to asthma. Both of these ideas have failed the test of truth; neither allergy nor early-life “cleanliness” leads to an increase in asthma. The latest theory to surface is that the pandemic of obesity is to blame, because it causes inflammation throughout the body. However, there are many obese people who are not asthmatics.
Newer research has the answer. In Qatar, researchers measured serum vitamin D levels in asthmatic children and compared those levels to levels of healthy non-asthmatic controls. Deficiency was defined as having levels below 20 ng/ml. Many other possible factors were also measured, such as nutritional practices, and various serum measurements such as calcium, phosphorus, alkaline phosphatase, magnesium, creatinine and Parathyroid hormone.
The results were these: asthmatic children had less exposure to sunlight (67%) and less physical activity (71.3%). Vitamin D deficiency was by far the strongest predictor of asthma; those who had the lowest vitamin D levels were nearly five-times more likely to have asthma.
The Scientific American’s editors must not to know that many scientists other than the aforementioned have suggested that vitamin D deficiency, caused by lack sunlight, leads to asthma. Much of the research was done before they published their article.
Researchers in Boston have hypothesized that the decrease in sunlight exposure and resultant vitamin D deficiency is responsible for the asthma epidemic. Others show the same facts: the increase in asthma has paralleled the decline in sunlight exposure, and asthma risk is 40% lower in children of women who have the highest vitamin D consumption during pregnancy.
A scientific experiment from Australia also demonstrated that when asthmatic mice were exposed to ultraviolet light, before being exposed to an asthma-causing allergen, asthma symptoms were reduced. Finally, another study from Spain showed that children exposed to the most sunlight have much lower risks of asthma. To me, it is amazing that the article in Scientific American never even mentioned the possibility of asthma being caused by deficiency of vitamin D brought on by lack of sunlight. Now that this latest research is in, It is my hope that they will correct the mistake and use their considerable prestige to promulgate the vitamin D/sunlight/asthma connection. It is time to return to the sun.
 Vital Signs: Asthma Prevalence, Disease characteristics, and self-Management education—United States, 2001-2009. MMWR 2011;60(17):547-552
 Bener A, Ehlayel MS, Tulic MK, Hamid Q. Vitamin D deficiency as a strong predictor of asthma in children. Int Arch Allergy Immunol 2012;157(2):168-75.
 Devereux, G. et al. Maternal vitamin D intake and early childhood wheezing. Am J Clin Nutr 2007;85:853-59
 Camargo, C. et al. Maternal intake of vitamin D during pregnancy and risk of recurrent wheeze in children at 3 y. Am J Clin Nutr 2007;85:788-95.
 Hart, P. et al. Sunlight may protect against asthma. Perth (Australia) Telethon institute for child health research. Quoted in Australian AP Oct 24, 2006.
 Arnedo-Pena, A et al. Sunny hours and variations in the prevalence of asthma in schoolchildren according to the International Study of Asthma and Allergies (ISAAC) Phase III in Spain. Int J Biometeorol 2011;55:423-434.