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
Although I occasionally try to balance the messages about tanning beds, this blog is meant neither to discourage nor promote their use. The readers should make up their minds after weighing the evidence. In a recent blog, I mentioned some positive messages about tanning-bed use, which included the following: Note: all references for the following list are found in the blog under footnote 1.
- Tanning-bed use is associated with a reduced risk of clots.
- Tanning-bed use is associated with increased vitamin D levels.
- Tanning-bed use is associated with stronger bones
- Tanning-bed use can cure psoriasis and eczema and tanning beds are often recommended by dermatologists.
- Tanning-bed use more than three times yearly is associated with a 40-50% reduced risk of endometrial cancer.
- Tanning-bed use is associated to lower breast-cancer risk.
After I posted the above information, a friend from Canada reminded me of research by Dr. Pelle Lindqvist and his colleagues, which demonstrated that both sun exposure and tanning-bed exposure reduced the risk of death during a 20-year study. Women who used tanning beds were 23% less likely to die of any cause than women who did not use them.
In addition, I remembered an older study that showed that tanning beds were able to take winter vitamin D levels up to summer levels in a period of five weeks.
So, along with the bad rap tanning beds are receiving, there is some good news. Who wouldn’t want to live longer in better health? Still, as with all decisions, weigh the evidence and then decide.
 Lindqvist P. Epstein E, Landin-Olsson M, Ingvar C, Nielsen K, Stenbeck M, Olsson H. Avoidance of sun exposure is a risk factor for all-cause mortality: Results from the Melanoma in Southern Sweden cohort
 Moan J, Lagunova Z, Cicarma E, Aksnes L, Dahlback A, Grant WB, Porojnicu AC. Sunbeds as vitamin D sources. Photochem Photobiol. 2009 Nov-Dec;85(6):1474-9.
By Marc Sorenson, EdD, Sunlight Institute
After coming across some research having to do with sun exposure and the seasonality of fractures, I thought it wise to share it with my readers.
In high latitude areas, which have far less sun availability than lower latitude areas, we would expect rates of hip fracture to be high, and such is the case. Sweden is a country that has large differences in latitude, and in research performed there it was shown that the higher the latitude and the lesser the sun exposure, the greater was the risk of hip fracture. In other words, significantly more hip fractures occurred in the northern part of the country compared to the middle and southern parts. Another Swedish investigation demonstrated that in men, hip fracture risk was 37.5% lower in summer than winter. Women had a 23.5% reduced risk in summer.
Research from Norway showed similar results. Hip fracture risk in men was 40% higher in winter than summer, and in women the risk was 25% higher.These fluctuations in seasonal hip fractures indicate a loss of bone mass during periods of low sun exposure (winter) and an increase in bone mass during periods of high sun exposure (summer). In other words, sun exposure is able to reverse bone loss, or osteoporosis. Other studies show similar patterns of bone strength based on sun exposure or lack thereof.
The importance of sunlight in maintaining and producing strong bones has been known since antiquity. Dr. Richard Hobday, author of The Healing Sun, writes the following comments and a history in an online article. “Traditionally, sunlight deprivation has been linked with weak or brittle bones. One of the earliest references to this was made more than two thousand years ago by the Greek historian Herodotus (480-425 BC), who noted a marked difference between the remains of the Egyptian and Persian casualties at the site of battle of Pelusium which took place in 525 BC:
‘At the place where this battle was fought I saw a very odd thing, which the natives had told me about. The bones still lay there, those of the Persian dead separate from those of the Egyptian, just as they were originally divided, and I noticed that the skulls of the Persians were so thin that the merest touch with a pebble will pierce them, but those of the Egyptians, on the other hand, are so tough that it is hardly possible to break them with a blow from a stone. I was told, very credibly, that the reason was that the Egyptians shave their heads from childhood, so that the bone of the skull is indurated by the action of the sun — this is why they hardly ever go bald, baldness being rarer in Egypt than anywhere else. This, then, explains the thickness of their skulls; and the thinness of the Persian’s skulls rests upon a similar principle: namely that they have always worn felt skull-caps, to guard their heads from the sun.’ Herodotus, ‘The Histories’”
The message is this: Don’t hide yourself from the sun; rather, embrace it in a safe manner, and that will protect your bones.
 Nilson F, Moniruzzaman S, Andersson R. A comparison of hip fracture incidence rates among elderly in Sweden by latitude and sun exposure. Scand J Public Health. 2014 Mar;42(2):201-6.
 Odén A, Kanis JA, McCloskey EV, Johansson H. The effect of latitude on the risk and seasonal variation in hip fracture in Sweden. J Bone Miner Res. 2014 Oct;29(10):2217-23.
 Solbakken SM1, Magnus JH, Meyer HE, Emaus N, Tell GS, Holvik K, Grimnes G, Forsmo S, Schei B, Søgaard AJ, Omsland TK.
 Grønskag AB1, Forsmo S, Romundstad P, Langhammer A, Schei B. Incidence and seasonal variation in hip fracture incidence among elderly women in Norway. The HUNT Study. Bone. 2010 May;46(5):1294-8.
 Richard Hobday. The Healing sun: Sunlight, Brittle Bones, and Osteoporosis. http://sunlightenment.com/the-healing-sun-sunlight-brittle-bones-and-osteoporosis/. (accessed February 5, 2016)
By Marc Sorenson, EdD…
Although most of the readers of this blog probably know why people are healthier and happier during summer, new research show that at least part of the reason in that human immunity is stronger during that season.[i] An interesting anti-inflammatory transcription factor, called ARNTL, has about 50% greater gene activity levels in the summer than in the winter. This would mean that infectious diseases would be more likely to be squelched in the summer, and it could provide a reason for the excess of inflammatory diseases like influenza in the winter. Of course, vitamin D levels and sunlight exposure are also lower in winter, and it is likely that these factors work in concert.
One of the researchers, John Todd, stated the following regarding sunlight exposure, inflammation, and vitamin D. “Given that our immune systems appear to put us at greater risk of disease related to excessive inflammation in colder, darker months, and given the benefits we already understand from vitamin D, it is perhaps understandable that people want to head off for some ‘winter sun’ to improve their health and well-being.”[ii]
Dr. Todd’s advice sounds great to me. Let’s all head to Cabo to catch some life-saving sunlight!
[i] Xaquin Castro Dopico, Marina Evangelou, Ricardo C. Ferreira, Hui Guo, Marcin L. Pekalski, Deborah J. Smyth, Nicholas Cooper, Oliver S. Burren, Anthony J. Fulford, Branwen J. Hennig, Andrew M. Prentice, Anette-G. Ziegler, Ezio Bonifacio, Chris Wallace & John A. Todd. Widespread seasonal gene expression reveals annual differences in human immunity and physiology. May 2015.
[ii] Agata Blaszczak-Boxe. People Are Healthier in the Summer (and Here’s Why). http://www.livescience.com/50806-seasonal-variation-human-genes-immune-inflammation.html
By Marc Sorenson, EdD, Sunlight Institute..
Just when one thinks that there is nothing new that sunlight can do, new research belies that idea. It has now been shown that among children who growth-hormone deficient, and are being treated for that deficiency, growth is more rapid during summer months. In a one-year study using 118 children from 14 countries as subjects, growth was measured and compared to the amount of sunlight received by the children. Those who were exposed to more sunlight had faster growth. The investigators also implicated a role for circadian-clock pathways in influencing growth (see my previous blogs on the importance of sunlight in correctly setting the circadian clock).
Although this research was claimed to be the first to demonstrate an influence of sunlight on accelerated growth among children being treated with growth hormone, another investigation from 2013 came to the same conclusion.  Others have also observed that children seem to grow more rapidly in summer.   
We want our children to have reasonable rates of growth, and the vitamin D produced by sunlight may produce larger and stronger bones. Or, it may be another factor such as nitric oxide, serotonin, endorphins or other less studied photoproducts. Whatever the mechanism, we now know that sunlight has one more critically important effect on human health, this time for our children.
 De Leonibus C, Chatelain P, Knight C, Clayton P, Stevens A. Effect of summer daylight exposure and genetic background on growth in growth hormone-deficient children. Pharmacogenomics J. 2015 Oct 27. [Epub ahead of print].
 Dorothy I Shulman, James Frane, and Barbara Lippe. Is there “seasonal” variation in height velocity in children treated with growth hormone? Data from the National Cooperative Growth Study. Int J Pediatr Endocrinol. 2013; 2013(1): 2.
 Marshall WA. Evaluation of growth rate in height over periods of less than one year. Arch Dis Child. 1971;46:414–420.
 Lee PA. Independence of seasonal variation of growth from temperature change. Growth. 1980;44:54–57.
By Marc Sorenson, EdD, Sunlight Institute
While contemplating my youth, growing up on our farm and ranch on the Utah/Nevada border, I mused on the amount of sunlight exposure that the hard summer work required. I was in the fields much of the time and spent a lot of time moving irrigation water, bucking hay bales and building and repairing fences. When the work allowed it, I shed my shirt until the sun became uncomfortable and then donned my cowboy hat and a long-sleeved shirt to protect against getting too much of that wonderful UV light. Some work, such as throwing hay bales on wagons, did not allow a bare body, because alfalfa hay is very scratchy. Much of the time, however, I was able to soak up the sun, going shirtless whether driving a tractor or chasing down recalcitrant cattle and sheep on my horse. My hands were often in the earth as I planted gardens and barley and alfalfa fields. Occasionally, I overdid the sun exposure and paid the price with a sunburn, but that was an infrequent occurrence. My friends called me “the brown man” although I am a blue-eyed, light skinned Caucasian. My tan was very deep; hence the moniker.
Those halcyon days of my youth were summer days, and I was never ill in that season; all of that sunlight kept me well, and it also helped to keep my mood elevated. Melanoma was never a worry for me or for the other farm boys and girls who lived in that area, and I have heard of no one who grew up there who ever contracted the disease, although they had the same ethnicity as I. Of course, lack of melanoma was to be expected, because people who spend much of their life in the sun are far less likely to contract melanoma than those whose stay indoors. For example, Diane Godar and her colleagues have presented evidence that outdoor workers, while receiving 3-9 times the sunlight exposure as indoor workers, have had no increase in melanoma since before 1940, whereas melanoma incidence in indoor workers has increased steadily and exponentially.  
This cogitating on my youth was triggered by reading an article entitled A senior moment: Get ‘down and dirty’ — Gardening is good for you! It discussed all the benefits of gardening and related some research regarding its therapeutic use:
Exercise that strengthens both the upper-and lower-body muscles, and especially hand strength
Reduces heart rate
Lowers blood pressure
Exposes the body to sunlight (hooray) to reset the circadian rhythms and combat depression
Promotes better nutrition
Gives a better sense of time
Of course, some of these benefits of gardening are really benefits of sunlight, as mentioned in the article. However, there may be another factor at play; when we connect with the earth, it improves our health, including heart health and mood through a transfer of electrons from the earth to our bodies.
What have we lost as we have adopted our sedentary, indoor lifestyles? Among other things, we have lost our good nutrition, our sunlight exposure and our contact with the earth. It is no wonder that working in a garden has such beneficial effects on our health! It gives us back at least some of our basic human health needs. So if you don’t have a garden, find one and get out in the sunlight!
Having been reminded of some of those vital needs, I am anticipating with alacrity my upcoming week at my Nevada ranch, where I will rusticate with my wife Vicki and my friends, Drs. Bill Grant and Adiel Tel-Oren. We will be soaking up the sunshine, feeling the dark mountain soil, eating nutritious foods and exulting in the beauty of the aspens and pines. We will also be renewing friendships with the birds, the ducks, the deer, the Elk, the wild turkeys and other wildlife that have no worries about us, because we don’t kill and eat them.
Sunlight, peace and friendships—it doesn’t get any better than this!
 Godar D, Landry, R, Lucas, A. Increased UVA exposures and decreased cutaneous Vitamin D3 levels may be responsible for the increasing incidence of melanoma. Med Hypotheses 2009;72(4):434-43
 Godar D. UV doses worldwide. Photochem Photobiol 2005;81:736–49.
 Thieden E, Philipsen PA, Sandby-Møller J, Wulf HC. UV radiation exposure related to age, sex, occupation, and sun behavior based on time-stamped personal dosimeter readings. Arch Dermatol 2004;140:197–203.
 Oschman JL, Chevalier G, Brown R. The effects of grounding (earthing) on inflammation, the immune response, wound healing, and prevention and treatment of chronic inflammatory and autoimmune diseases. J Inflamm Res. 2015 Mar 24;8:83-96.
 Chevalier G, Sinatra ST, Oschman JL, Delany RM. Earthing (grounding) the human body reduces blood viscosity-a major factor in cardiovascular disease. J Altern Complement Med. 2013 Feb;19(2):102-10
 Chevalier G. The effect of grounding the human body on mood. Psychol Rep. 2015 Apr;116(2):534-43