UVB exposure benefits by Marc Sorenson, EdD. Sunlight Institute…
UVB is a spectrum of sunlight that is responsible for stimulation of vitamin D production in the skin. It also has many other effects, including the suppression of inflammation in the skin, and thus has been used to very successfully treat skin diseases such as psoriasis and eczema.   
Since inflammation is also necessary to produce the condition of atherosclerosis (arterial plugging or occlusion) in arteries, it would be interesting to know whether UVB light might also have the same anti-inflammatory effects in those arteries. If so, the UVB effect could inhibit or eliminate atherosclerosis, and by so doing provide an entirely new treatment for heart disease and other vascular events such as stroke and intermittent claudication.
The idea that UVB could prevent atherosclerosis by reducing inflammation in arteries was recently studied by Japanese researchers.  Using a mouse model, they demonstrated that UVB light irradiation, once weekly for 14 weeks, leads to an increase in the action of T-regulatory cells that inhibit inflammation. In addition, UVB exposure also reduced the production of another type of T-cell that is pro-inflammatory, and thereby proatherogenic (leading to the production of atherosclerosis). These two effects of UVB light reduce the development and progression of atherosclerosis. Or stated differently, the research shows that sun exposure is critically-important therapy to reduce and prevent heart and other vascular diseases.
Protect your heart by being sure to obtain sufficient non-burning UVB light from sun exposure or other sources such as the UVB lamps used by the researchers. It is important to note that neither skin cancer nor skin inflammation were observed following UVB exposure.
This is another breakthrough study that emphasizes the necessity of sun exposure for human health.
 National Psoriasis Foundation web site Oct. 2005.
 Yelverton CB, Kulkarni AS, Balkrishnan R, Feldman SR. Home ultraviolet B phototherapy: a cost-effective option for severe psoriasis. Manag Care Interface 2006;19:33-36, 39.
 Situm M, Bulat V, Majcen K, Dzapo A, Jezovita J. Benefits of controlled ultraviolet radiation in the treatment of dermatological diseases. Coll Antropol. 2014 Dec;38(4):1249-53.
 Gupta A, Arora TC, Jindal A, Bhadoria AS. Efficacy of narrowband ultraviolet B phototherapy and levels of serum vitamin D3 in psoriasis: A prospective study. Indian Dermatol Online J. 2016 Mar-Apr;7(2):87-92.
 Naoto Sasaki, Tomoya Yamashita, Kazuyuki Kasahara, Atsushi Fukunaga, Tomoyuki Yamaguchi, et al. UVB Exposure Prevents Atherosclerosis by Regulating Immunoinflammatory Responses. Arterioscler Thromb Vasc Biol. 2016;36:00-00.
 Hafid Ait-Oufella, Andrew P. Sage. Editorial. The Sunlight. A New Immunomodulatory Approach of Atherosclerosis. (Arterioscler Thromb Vasc Biol. 2017;37:7-9. DOI: 10.1161/ATVBAHA.116.308637.)
Sun exposure and health By Marc Sorenson, EdD, Sunlight Institute…
New research shows that sunlight boosts the effectiveness of T-cells, an integral part of the immune system. T-cells are a type of lymphocyte that recognizes and binds to foreign invaders, thereby rendering them harmless. This is an important new finding, which demonstrates another beneficial effect of sun—one that has no relationship to vitamin D.
The key player in this action is the blue-light spectrum of sunlight that stimulates hydrogen peroxide production. The hydrogen peroxide (HP) causes T-cells to move to the site of infection, and it (HP) is also involved in the killing of noxious bacteria. Dr. Gerard Ahern, one of the primary investigators, stated it in this way: “T cells, whether they are helper or killer, need to move to do their work, which is to get to the site of an infection and orchestrate a response. This study shows that sunlight directly activates key immune cells by increasing their movement.”
Also interesting is the fact that the skin has a large share of the total T-cells in humans, about twice the number circulating in the blood. Think about this magnificent body of ours! It is programmed to immediately respond to any invasions that may occur in the skin, and sun exposure, if we take full advantage of it, immediately accelerates the process. Then, when the t-cells are activated by the blue light, they can move rapidly to other body areas where they can be utilized.
Sun exposure has also been found to have an exceptionally important and positive effect on autoimmune diseases such as lupus, MS, rheumatoid arthritis and others, many of which have been found to associate with low solar radiation and vitamin D. In this case, a different type of T-cell, called a regulatory T-cell, attacks the body’s own tissue, mistaking it for a foreign invader, and causes severe damage. The mechanism of autoimmune disease prevention by sunlight may be the suppression of regulatory T cells, in a manner that impedes the immune system’s attacks on its own tissues. 
Sunlight is one of God’s (or Nature’s) greatest miracles. Be sure to receive your full contingent of wonderful, non-burning sun.
 Thieu X. Phan, Barbara Jaruga, Sandeep C. Pingle, Bidhan C. Bandyopadhyay, Gerard P. Ahern. Intrinsic Photosensitivity Enhances Motility of T Lymphocytes. Scientific Reports, 2016;6:39479
 Schwalfenberg GK. Solar radiation and vitamin D: mitigating environmental factors in autoimmune disease. J Environ Public Health. 2012;2012:619381.
ArtukovićM1, Ikić M, Kustelega J, Artuković IN, Kaliterna DM. Influence of UV radiation on immunological system and occurrence of autoimmune diseases. Coll Antropol. 2010 Apr;34 Suppl 2:175-8.
Marsh-Wakefield F, Byrne SN. Photoimmunology and Multiple Sclerosis. Curr Top Behav Neurosci. 2015;26:117-41.
Tanning bed use, By Marc Sorenson, EdD. Sunlight Institute.
Sun exposure and tanning-bed exposure have been much maligned by those who would increase sunscreen sales and other “protection” against melanoma. So a new paper has been written regarding the truth about tanning beds. According to this paper, Risk of melanoma with tanning beds is slightly associated with home use, but there is no significant increase in risk with beds used in tanning salons. This is according to a soon-to-be-published analysis of studies that differentiated between home-use tanning beds and salon use of tanning beds.
The analysis showed that when all tanning devices were considered together, tanning bed use was associated with a 15%-20% increased risk of melanoma. However, when home-use tanning was separated from salon use, salon use showed only a 5% increased risk, which was not significant. In other words, there may have been no risk whatever. In fact, in three of the studies that were part of the analysis, overall use of tanning beds associated to a lessened risk of melanoma.
Therefore, if there is any increased risk of melanoma with tanning-bed use, it is all due to the use of home units. This is what we might expect, since salons take care to assess skin type and monitor the time spent in the unit.
Before we decide to eschew the use of home units, however, we should also take into consideration the very healthful benefits of tanning-bed use in general. Here are a few well-documented facts about the benefits:
- 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.
- A 20- year study demonstrated that both sun exposure and tanning-bed exposure reduced the risk of death; women who used tanning beds were 23% less likely to die of any cause than women who did not use them.
The key to safe tanning-bed use is the same key as for safe sun exposure: Don’t be taken in by the anti-sun, anti-tanning movement.
 Hoel, D. Commercial Tanning Salons and Melanoma Risk. Letter to the editor, Dermato-endocrinology. Not yet published.
 Lindqvist PG, Epstein E, Olsson H. Does an active sun exposure habit lower the risk of venous thrombotic events? A D-lightful hypothesis. J Thromb Haemost. 2009 Apr; 7(4):605-10.
 Holick, M. Boston University. “Effects Of Vitamin D And Skin’s Physiology Examined.” Science Daily 21 February 2008 <http://www.sciencedaily.com¬ /releases/2008/02/080220161707.htm>.
 Tangpricha V, Turner A, Spina C, Decastro S, Chen TC, Holick MF. Tanning is associated with optimal vitamin D status (serum 25-hydroxyvitamin D concentration) and higher bone mineral density. Am J Clin Nutr 2004;80:1645-49.
 Radack KP, Farhangian ME, Anderson KL, Feldman SR. A review of the use of tanning beds as a dermatological treatment. Dermatol Ther (Heidelb). 2015 Mar;5(1):37-51.
 Epstein E, Lindqvist PG, Geppert B, Olsson H. A population-based cohort study on sun habits and endometrial cancer. Br J Cancer. 2009 Aug 4;101(3):537-40.
 Yang L, Veierød MB, Löf M, Sandin S, Adami HO, Weiderpass E. Prospective study of UV exposure and cancer incidence among Swedish women. J Intern Med. 2014 Jul;276(1):77-86
 Lindqvist PG, 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. J Intern Med. 2014 Jul;276(1):77-86.
Sun exposure Information by Marc Sorenson, EdD. Sunlight Institute.
There are 62,700 cases of kidney cancer and 14,240 deaths annually. Kidney cancer incidence has tripled since the early 1980s, and some researchers have felt that environmental factors may have played a part in that worrisome increase. One of those factors may be sun exposure, which may be vital to the prevention of the disease. The newest research measured sun exposure, which was based on the average number of hours per day outdoors in the summer, during different periods of life. The researchers also took into consideration the age of the subjects and adjusted the data for other factors that may associate to kidney cancer.
These were some of the research results:
- Higher summer sun exposure at age 40+ years, but not at younger ages, was associated with a significantly lower risk of thyroid cancer. When comparing the highest quartile (fourth) of sun exposure to the lowest quartile, there was a 44% reduction in risk.
- Average lifetime sun exposure was not associated with thyroid-cancer risk.
- Recent summer sun exposure was closely associated with a decreased risk of thyroid cancer.
One of the salient points, in my mind, is that the best sun exposure is that which is habitual or consistent. In the case of kidney cancer, sun exposure in the past does not indicate that the disease will be avoided in the future. Only recent sun exposure provides protection. However, this is not necessarily true of other diseases; in the case of breast and prostate cancers, childhood sun exposure is associated with a lesser risk of the diseases in adulthood.
Previous research has also confirmed the importance of sun exposure on kidney-cancer prevention. There is a strong inverse correlation between sun exposure and kidney cancer. For example, one study that used NMSC as a measure of sun exposure, determined that sun exposure reduced the risk of several cancers, including kidney cancer, from 35% to 42%. Kidney cancer mortality rates were found to be strongly inversely correlated with solar UVB doses in Dr. William Grant’s 2002 and 2006 ecological studies. 
Recent research by Dr. Sara Karami and colleagues, demonstrates that in women, there is a significant reduction in kidney cancer with high levels of sun exposure. Those women with the highest fourth of sun exposure showed a 33% reduction in risk. Interestingly, the data was adjusted for vitamin D intake, and the results still showed sun exposure to have a stand-alone protective influence on kidney cancer—another indication that sun exposure has protective effects beyond vitamin D production.
Remember that a lifetime habit of non-burning sun exposure will always provide the best health outcomes.
 Rachel D Zamoiski, Elizabeth K. Cahoon, D. Michal Freedman, et al. Prospective study of ultraviolet radiation exposure and thyroid cancer risk in the United States. Cancer Epidemiol Biomarkers Prev Published Online First December 2, 2016.
 Tuohimaa P, Pukkala E, Scélo G, Olsen JH, Brewster DH, Hemminki K, Tracey E, Weiderpass E, Kliewer EV, Pompe-Kirn V, McBride ML, Martos C, Chia KS, Tonita JM, Jonasson JG, Boffetta P, Brennan P. Does solar exposure, as indicated by the non-melanoma skin cancers, protect from solid cancers: vitamin D as a possible explanation. Eur J Cancer 2007;43(11):1701-12
 Grant WB. An estimate of premature cancer mortality in the U.S. due to inadequate doses of solar ultraviolet-B radiation. Cancer. 2002 Mar 15;94(6):1867-75.
 Grant WB, Garland CF. The association of solar ultraviolet B (UVB) with reducing risk of cancer: multifactorial ecologic analysis of geographic variation in age-adjusted cancer mortality rates. Anticancer Res. 2006 Jul-Aug;26(4A):2687-99.
 Karami S, Colt JS, Stewart PA, Schwartz K, Davis FG, Ruterbusch JJ, Chow WH, Wacholder S, Graubard BI, Purdue MP, MooreLE. Short Report: A case-control study of occupational sun exposure and renal cancer risk. Int J Cancer. 2015 Oct 27.
By Marc Sorenson, EdD. For sun exposure…
It should be well-known by now, but the relationship between sun exposure and myopia (nearsightedness) is still being studied. And as before, the answer is the same: sun deprivation is associated to a greater myopia risk. The difference in this research was the study population, which was a random sample of participants 65 years and older from Europe. Among the factors that the researchers considered important, were vitamin D blood levels, vitamin D polymorphisms, ultraviolet B radiation (UVB), and years in education. Of these factors, only ultraviolet B radiation (UVB) was associated with reduced odds for myopia, especially if higher UVB exposure occurred during adolescence and early adulthood. This is another research paper that shows sun exposure to be protective against a disease, independent of vitamin D.
The authors of the study made this conclusion: “This study, while not designed to determine cause and effect relationships, suggests that increased ultraviolet B exposure, a marker of sunlight exposure, is associated with reduced myopia.
This is one in a long line of studies that show the relationship of sun exposure to myopia, and it doesn’t take a rocket scientist to determine that myopia is caused by lack of sun exposure. The evidence has been building for years. For example, one of the studies showed that the lowest risk of myopia among 12-year-old students was found among those who reported the highest levels of outdoor activity. Some might surmise that the key ingredient was exercise, but that idea was refuted by the fact that there was no association between indoor activity and myopia. Something besides exercise had to be leading to the lower risk of myopia among children who were actively outdoors; it had to be sun. The lower risk of myopia persisted after adjusting for genetic factors, ethnicity and the amount of near work. This is important, because for many years there was an assumption that long hours of study indoors, staring closely at books (near work) and never focusing on distant objects, led to myopia. This study belied that error.
This same research showed that the prevalence of myopia among Chinese children living in Singapore was 29.1%, whereas Chinese children living in Sydney, Australia, had a prevalence rate of only 3.3%. The children in Sydney spent about 13.8 hours per week outdoors compared to 3.05 hours in Singapore. In other words, the children who spent most or their lives indoors had 9.5 times the risk of developing myopia!
Depriving either adults or children of their time in the sunlight leads to myriad illnesses, only one of which is myopia. When will we learn?
 Katie M. Williams, FRCOphth; Graham C. G. Bentham, MA; Ian S. Young, MD; et al Association Between Myopia, Ultraviolet B Radiation Exposure, Serum Vitamin D Concentrations, and Genetic Polymorphisms in Vitamin D Metabolic Pathways in a Multicountry European Study. Published Online: December 1, 2016. doi:10.1001/jamaophthalmol.2016.4752
 Rose KA, Morgan IG, J, Kifley A, Huynh S, Smith W, Mitchell P. Outdoor activity reduces the prevalence of myopia in children. Ophthalmology 2008 Aug;115(8):1279-85.
By Marc Sorenson, EdD, promoting sun exposure..
The world of science is waking up! New research states that 330,000 lives could be saved by optimizing vitamin D levels through sun exposure. That compares to 450,000 deaths linked to tobacco. This is to be expected, since a Swedish study demonstrated that over a 20- year period, women who avoided the sun were TWICE AS LIKELY TO DIE OF ANY CAUSE, as women who were sun-seekers,  and the researchers stated the following: “Nonsmokers who avoided sun exposure had a life expectancy similar to smokers in the highest sun exposure group, indicating that avoidance of sun exposure is a risk factor for death of a similar magnitude as smoking.”
It is no surprise that sun exposure saves lives. Here are a few facts that I have written about on the Sunlight Institute site. Go to news and search the fact you would like to read.
- As sun exposure in the U.S. has DECREASED by 90% during the last century, melanoma incidence has INCREASED BY 3,000%.
- A Spanish study shows that women who seek the sun have one-eleventh the hip fracture risk as those who avoid sun.
- Men who work outdoors have half the risk of melanoma as those who work indoors.
- Women who totally avoid the sun have 10-times the risk of breast cancer as those who embrace the sun.
- Sun exposure increases nitric oxide production, which leads to a decrease in heart attack risk.
- Vitamin D, the sunshine vitamin, is essential to human survival, and sun exposure is the only natural way to obtain it. Sunbathing can produce 20,000 units of vitamin D in 20 minutes of whole-body exposure.
- Sun exposure dramatically improves mood through the production of serotonin and endorphin.
- Beyond vitamin D, sun exposure also stimulates the production of endorphin, nitric oxide and BDNF, all of which are vital to human health.
- Regular sun exposure also reduces high blood pressure, psoriasis and multiple sclerosis (MS).
- So enjoy your sunshine, but don’t burn.
 David G. Hoel, Marianne Berwick, Frank R. de Gruijl & Michael F. Holick
(2016) The risks and benefits of sun exposure 2016, Dermato-Endocrinology, 8:1, e1248325,
 Lindqvist PG, Epstein E, Nielsen K, Landin-Olsson M, Ingvar C, Olsson H. Avoidance of sun exposure as a risk factor for major causes of death: a competing risk analysis of the Melanoma in Southern Sweden cohort.
J Intern Med. 2016 Oct;280(4):375-87
 Lindqvist PG, 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. J Intern Med. 2014 Jul;276(1):77-86
By Marc Sorenson, EdD. Sun exposure–Did you know that sun exposure can kill germs both inside and outside the body? Here is a little history.
The German microbiologist Robert Koch, who isolated TB bacteria in 1882, showed that sun could kill the bacteria. However, even earlier, in 1877, other researchers discovered that sugar water left in the shade became cloudy, indicative of bacterial growth, but if exposed to sun, it remained clear.
Sun is a potent bactericide. Dr. Kime, in his book, Sunlight could Save Your Life, reviewed the results of research conducted between 1886 and 1909. It showed that the following bacteria were killed by ultraviolet light: anthrax, plague, streptococci, tubercle bacillus, cholera, staphylococcus, colon bacillus and dysentery bacillus. Sun was virtually forgotten with the advent of antibiotic drugs, but now the interest has returned. While watching a newscast, I noticed the news ticker announcing, “Sunshine is the most effective anti-infection therapy.” But is this really news? Dr. Kime cites several early studies on sun and infectious diseases that were performed about the same time as the advent of antibiotics. Reports in the scientific literature in the 1940s showed that sun killed infectious bacteria or viruses. Kime states …“a number of patients, having such various infections and diseases as blood poisoning, childbirth infections, peritonitis, viral pneumonia, mumps, and bronchial asthma were treated with ultraviolet light therapy to their blood.”          They were, in fact, treated very successfully.
Dr. Kime also cited research showing that UV therapy killed the flu virus outside the body and destroyed cancer-producing viruses. He reported good results in his own practice in treating fungal infections with sun therapy.
Other early research showed that all bacteria within eight feet of low-intensity UV lights were killed in ten minutes.
While visiting in Mexico, a friend invited me (MBS) to tour a bottled-water plant in a town called Juchipila. It was interesting that the water was exposed to UV as a means of purification. It must work, because I drank it during my visit without ill effects. Sun also kills E. coli bacteria in twelve feet of seawater and in waste stabilization ponds. I also find it interesting that the Sonicare electric-toothbrush company now sells a sanitizer based on UV. The brush, after use is placed in the UV sanitizer, and the company claims that it kills millions of germs in 10 minutes.
The insanity of sun avoidance becomes more evident every day. Safely embrace the sun and save your life!
 Downes, A. Researches on the effect of light upon bacteria and other organisms. Proc Roy Soc Med 1877;26:488. Cited in Kime, Z. sun Could Save Your Life. World Health Publications, Penryn, CA 1980:126-30.
 Miley, G. The Knott technic of ultraviolet blood irradiation in acute pyogenic infections. New York J Med 1942;42:38.
 Miley, G. The Knott technic of ultraviolet blood irradiation in acute pyogenic infections. New York J Med 1942;42:38.
 Rebbeck, E. Ultraviolet irradiation of auto-transfused blood in the treatment of puerperal sepsis. Amer J Surg 1941;54:691
 Rebbeck, E. Ultraviolet irradiation of autotransfused blood in the treatment of postabortal sepsis. Amer J Surg 1942;55:476.
 Rebbeck, E. Ultraviolet irradiation of the blood in the treatment of escherichia coli septicemia. Arch Phys Ther 1943;24:158.
 Rebbeck, E. The Knott technic of ultraviolet blood irradiation as a control of infection in peritonitis. Amer J Gastroenterol 1943;10:1-26
 Hancock, V. Irradiated blood transfusions in the treatment of infections. Northwest Med 1934;33:200.
 Barrett, H. Five years experience with hemo-irradiation according to the Knott technic. Am J Surg 1943;61:42
 Barrett, H. The irradiation of auto-transfused blood by ultraviolet spectral energy: results of therapy in 110 cases. Med Clin N Amer 1940;24:723
 Miley, G. The present status of ultraviolet blood irradiation. Arch Phys Ther 1944;25:357.
 Hollaender, A. The inactivating effect of monochromatic ultraviolet radiation on influenza virus. J Bact 1944;48:447.
 Heding LD, Schaller JP, Blakeslee JR, Olsen RG.Inactivation of tumor cell-associated feline oncornavirus for preparation of an infectious virus-free tumor cell immunogen. Cancer Res 1976;36:1647.
 Hart, D. Sterilization of the air in the operating room by special antibacterial radiant energy. J Thorac Cardiovasc Surg 1936;6:45.
Gameson, A. Field studies on effect of daylight on mortality of coliform bacteria. Water Res 1967;1:279.
Sun exposure By Marc Sorenson, EdD… Sunlight Institute…
Nearly thirty years ago, I talked to many “experts” who told me that our mostly vegetarian diet could not help those who suffered from arthritis, because “diet has nothing to do with arthritis.” However, I was able to find one or two pieces of research that indicated that arthritis was indeed associated with poor nutrition and could be ameliorated or reversed by proper nutritional habits.
Then, during our many years in the health and fitness resort business, we observed many seeming miracles with our arthritic attendees. One woman, who could not play piano due to her arthritic hands, was able to play again in less than two weeks. Her reduction in inflammation was visible and her increase in range-of motion was remarkable. Her husband, who could not walk more than about a hundred yards when they arrived, was walking a mile after two weeks as his arthritic hips recovered range of motion and his muscles gained strength.
Through serendipity, a few days ago, a piece of research appeared to me—a study that I wished I had known about 30 years ago. It was published in 1935, and was titled, THE TREATMENT OF CHRONIC ARTHRITIS BY DIET AND SUNLIGHT. The author studied a group of seventy-two arthritic patients whom he treated with diet, calling his program the “depletion diet.” The diet was bulky and very high in protective foods, but contained very little protein and fat. He stated that “Thus in seventy-two cases treated by diet, five were not improved, thirteen were slightly improved, thirty-nine were much improved, and fifteen were completely relieved.”
Other treatment included sunbathing, and the doctor considered it so important that he had his patients move to an area where they could sunbathe for at least eight weeks per year. He felt that it was almost indispensable.
Our program was somewhat similar, although our diet was much stricter. We were fortunate that we already operated our resort in an area where the sun shines about 260 days per year.
Other research has shown a correlation between arthritis and sun exposure. A paper by Dr. Viera and colleagues demonstrated that at high latitudes, where sun exposure is considerably less available, the rate of rheumatoid arthritis (RA) is much higher than at lower latitudes. RA is also more severe in winter, a time of less sun exposure.
So give up the junk food and safely embrace the sun. Your joints will love it!
 Langsworth, L. THE TREATMENT OF CHRONIC ARTHRITIS BY DIET AND SUNLIGHT. CALIFORNIA AND WESTERN MEDICINE. March, 1935.
Vieira VM, Hart JE, Webster TF, Weinberg J, Puett R, Laden F, Costenbader KH, Karlson EW. Association between Residences in U.S. Northern Latitudes and Rheumatoid Arthritis: A Spatial Analysis of the Nurses’ Health Study. Environ Health Perspect. 2010 Mar 25. [Epub ahead of print]
Cutolo M, Otsa K, Uprus M, Paolino S, Seriolo B. Vitamin D in rheumatoid arthritis. Autoimmun Rev 2007;7:59-64
By Marc Sorenson, EdD… Sun exposure benefits…
A very important paper regarding the necessity for sun exposure has recently been published by the journal Medical Hypothesis. It is entitled Regular sun exposure benefits health, and it discusses the pros and cons of sun exposure. One of the salient statements in the paper is that intermittent sun exposure may increase the risk of skin cancer, whereas regular exposure to sunlight might benefit health. For those of us who have for years studied the beneficial effects of sun exposure, the use of the word “might” is the only drawback to the statement. There is no doubt that for the majority of the population, regular sun exposure absolutely protects and enhances health.
Among the diseases mentioned as being reduced or prevented by regular sun exposure are the following:
- Cancers: Colon, breast, prostate and non-Hodgkin lymphoma
- Multiple sclerosis
As the authors mention, most of these positive effects of sun exposure were previously ascribed to Vitamin D, but they point out that immune system function is enhanced by sun exposure beyond the effects of vitamin D, and list other non-vitamin D benefits of the sun, including:
- Production of nitric oxide
- Production of melatonin
- Production of serotonin
- Regulation of the circadian clock
I have discussed most of these items on the Sunlight Institute web site, but it was good to see new research that, in particular, separated the health benefits of sun exposure from vitamin D production. The idea that has become popularized during the past decade, that all benefits of sun exposure come from increased vitamin D production, is simply not true and can lead to the supplementation of vitamin D as a “cure” for diseases that may not be influenced by that hormone.
Of course, vitamin D is an exceptionally important photoproduct, and the only natural way to attain it is by exposure to the sun or to other sources of UVB light (such as a sunlamp or a tanning bed). The beauty of using these sources, rather than a vitamin-D capsule, is that all of the benefits of nitric oxide, melatonin, serotonin and circadian entrainment are included in the package.
Safely enjoy the sun, and you then will also safely enjoy better health. Remember not to burn, and to gradually develop a good tan.
 van der Rhee H, de Vries, E, Coebergh, J. Regular sun exposure benefits health. Medical Hypotheses 97 (2016) 34–37
The importance of sun exposure for colon cancer
By Marc Sorenson, EdD, Sunlight Institute…
In 1980, Cedric and Frank Garland published a seminal paper showing a relationship between colon cancer and geographical location. They observed dramatically higher rates of colon cancer in the Northeast, where there is a paucity of sun exposure, compared with the South and West where sun is more prevalent. They hypothesized that vitamin D, stimulated in the skin by sun, reduced the risk of colon cancer. They pointed out the correlation between colon cancer and UVR exposure, stating particularly that “New Mexico and Arizona had the highest statewide mean solar radiation values (500 gm-cal/cm2). These states experienced colon cancer rates for white males of 6.7 and 10.1 per 100 000 population, respectively, over the period 1959–61. New York, New Hampshire, and Vermont had the lowest statewide mean solar radiation values (300 gm-cal/cm2) and experienced colon cancer rates for white males of 17.3, 15.3, and 11.3 per 100 000 populations, respectively, during the same period.”
Other studies have corroborated the correlation between high sun exposure and low colon cancer rates. Japanese research demonstrated that people in the areas of highest solar radiation exhibit the lowest rates of colon cancer, with those living in the areas of highest sun exposure having about half the colon cancer rate as those living in the lowest.A significant aspect of this research is that sun correlated to a reduced risk of cancer even where vitamin D consumption was high, indicating that sun exposure (as noted with prostate cancer and breast cancer, above) may have beneficial influences on cancer beyond its stimulation of vitamin D production, or that vitamin D produced in the skin by sun exposure may have advantages over that consumed through food or supplements.
The research by Dr. Mizoue is not the only investigation that differentiated the effects of UV light exposure and vitamin D/colon cancer. A six-week study by Dr. Rebel and colleagues used mice with intestinal tumors—tumors that often progress to cancers. It was shown that the mice given either UV radiation or vitamin-D supplementation reduced the tumor load when compared to mice who received no treatment. However, only the UV treatments prevented the tumors from progressing to cancer. Still other recent research has demonstrated that sun, not vitamin D, may produce all of the positive effects on colon cancer. The researchers performed a 140-day investigation involving rats that had colon adenomas (a precursor to full-blown colon cancer) induced in their colons. The rats were given either vitamin D3 as supplements, or the stored form of vitamin D, 25(OH)D3, in differing amounts. With low dose vitamin D in either form, no reduction in either existing adenomas or emerging tumors were seen. In higher doses, there was a dose-dependent increase in colon tumor numbers in both male and female rats. The researchers said the following in their concluding statement: “Thus, the association between sun exposure and the incidence of colon cancer may involve factors other than vitamin D concentrations. Alternative hypotheses warrant investigation. Furthermore, this study provides preliminary evidence for the need for caution regarding vitamin D supplementation of humans at higher doses, especially in individuals with sufficient serum 25(OH)D3 concentrations.” The takeaway from this research is this: sun is protective against colon cancer in rats (and probably in humans), independent of vitamin D—another reason to safely embrace the sun.
These studies again demonstrate that we cannot substitute vitamin D pills for sun in many cases. UV light from sun or sun lamps is always the best option to cover all prevention and healing possibilities.
 Garland CF, Garland FC. Do sun and vitamin D reduce the likelihood of colon cancer? Int. J. Epidemiol 1980;9:227–31.
 Mizoue, T. Ecological study of solar radiation and cancer mortality in Japan. Health Phys 2004;87:532-38.
 Rebel H1, der Spek CD, Salvatori D, van Leeuwen JP, Robanus-Maandag EC, de Gruijl FR. UV exposure inhibits intestinal tumor growth and progression to malignancy in intestine-specific Apc mutant mice kept on low vitamin D diet. Int J Cancer. 2015 Jan 15;136(2):271-7.
 Irving AA, Plum LA, Blaser WJ, Ford MR, Weng C, Clipson L, DeLuca HF, Dove WF. Cholecalciferol or 25-hydroxycholecalciferol neither prevents nor treats adenomas in a rat model of familial colon cancer. J Nutr. 2015 Feb;145(2):291-8.