Leprosy is a bacterial disease that has been historically mentioned as a scourge, when it was considered to be incurable and disfiguring. Symptoms that develop include granulomas (inflammation caused by a collection of immune cells) of the nerves, respiratory tract, skin, and eyes. This may result in a lack of ability to feel pain, followed by the loss of parts of extremities, due to repeated injuries or infection of unnoticed wounds. About 180,000 people worldwide are diagnosed with leprosy yearly, and about 100 people are diagnosed in the U.S. each year. Leprosy has been considered to be a disease which has been eradicated, but such is not the case. For example, an article in an Indian paper shows it is much more prevalent in highly urbanized areas (areas of less sun) than in rural or less polluted areas (areas of more sun). Also, when the bacteria that cause leprosy are exposed to ultraviolet light, the procedure kills half of the bacteria. Therefore, sunlight may fight leprosy as it fights other bacteria, by stopping them at the source. 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 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.” I believe that is true; sun exposure is provided to the earth to help prevent myriad diseases, but many of us try to avoid its healing powers. Non-burning sun exposure is a magnificent healer, and also a preventer of disease in those cases where it cleans the environment of noxious microorganisms.
 Kumar, R. Urbanites More Prone to Leprosy. Merinews April 14, 2008. (available at http://www.merinews.com/catFull.jsp?articleID=132447)
 Truman RW, Gillis TP. The effect of ultraviolet light radiation on Mycobacterium leprae. Int J Lepr Other Mycobact Dis. 2000 Mar;68(1):11-7.
Sun exposure is crucial to preventing multiple sclerosis (MS), the terrible, debilitating autoimmune disease in which T-cells initiate an inflammatory response against myelin, the protective cover of nerves., This leaves the nerves bare and susceptible to “short circuiting,” a process known as demyelination. This attack prevents proper functioning within the brain and body, which leads to a variety of symptoms like vision changes, muscle spasms, and numbness. These symptoms profoundly decrease the ability to function and destroy the quality of life.
We have known for decades that people who live in areas of low sun exposure, such as far-northern or far southern countries, have a far greater risk of contracting MS than those who live in countries closer to the equator. In fact, there is more than 100 times the risk of MS in far northern as in equatorial areas, where sun is intense, and the rate of MS approaches zero.,,
I ran across an interesting study demonstrating that the age at which the low sun exposure occurs is also a predictive factor in the risk of MS. It showed that in Norway, the amount of sun exposure in the period of life between 16-18 years of age was critical in predicting the disease. Those youngsters who experienced the lowest sun exposure during those ages were 83% more likely to develop MS. The same research showed that in Italy the critical period was between birth and age 5 years, with those receiving the lowest sun exposure being 56% more likely to develop MS.
I spite of incontrovertible research that proves regular, non-burning sun exposure is critical for human health, the sunscare movement continues to promote the idea that we should avoid the sun. The blood is on their hands.
 Racke, M. Immunopathogenesis of multiple sclerosis. Ann Indian Acad Neurol. 2009 Oct–Dec; 12(4): 215–220.
 Markovic-Plese S, McFarland HF. Immunopathogenesis of the multiple sclerosis lesion. Curr Neurol Neurosci Rep 2001;1:257-62
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 Bjørnevik K, Riise T, Casetta I, Drulovic J, Granieri E. et al. Sun exposure and multiple sclerosis risk in Norway and Italy: The EnvIMS study. Mult Scler. 2014 Jul;20(8):1042-9.
Diabetes and sun exposure By Marc Sorenson, EdD.
Diabetes is a disease of chronically high blood glucose leading to blindness, nerve damage, heart disease and numerous other maladies. Diabetes comes in two forms: (1) Type-one, in which there is damage to the islet cells of the pancreas. This is usually due to an autoimmune response, and the damage prevents production of insulin responsible for removing glucose from the blood. (2) Type-two, in which insulin is produced, but blood glucose remain high due to insulin resistance. In this article, we will discuss type-two, which is by far the most common type. As with heart and vascular disease, we must realize a paucity of sunlight is not the cause of either type of diabetes; rather it is caused by deleterious nutrition habits, primarily high meat consumption,   sugar consumption,  egg consumption, low consumption of fruits and vegetables, and too many fried foods. In the case of type-one, milk consumption may be the most important nutritional factor. However, sunlight may act as a prophylactic against either type of diabetes. With either type of diabetes, it is not usually the diabetes that kills, but other diseases resulting from it.
There are several studies showing a relationship between type-two diabetes mellitus (DM) and sun exposure or UVB exposure. One paper showed blood-sugar levels were lower during the summer, and another demonstrated exposure to sun lamps increased insulin secretion. It has also been found there is a direct and significant association between low 25(OH)D levels (a surrogate measure for low sun exposure) and increased risk of type-two.
In addition, a meta-analysis produced moderate evidence that recreational sun exposure is associated with a reduced risk of type-two. The study was undertaken because of the observation by researchers showing that although higher 25(OH)D levels were consistently associated with a lower risk of diabetes, supplementing 25(OH)D had shown no such effects. They hypothesized sun exposure could have influences not related to vitamin D, and such seems to have been the case.
Another of the more important investigations showed that women who had “active sun exposure habits” had a 30% reduced risk of type-two.
Diabetes is increasing very rapidly and may someday overwhelm the health-care system. In my opinion, it is the most easily reversed of all degenerative diseases, so this is a tragedy. Proper nutrition, exercise and safe sun exposure can prevent almost all type-two diabetes. At our former resort, about two-thirds of type-two diabetics were free of all medication in two weeks. It is a totally unnecessary disease. If you don’t have it, prevent it. If you have it, reverse it. Start today.
FeskensEJ, Sluik D, van WoudenberghGJ. Meat consumption is an important risk factor Meat consumption, diabetes, and its complications. Curr Diab Rep. 2013 Apr;13(2):298-306.
Kim Y, Keogh J, Clifton P. A review of potential metabolic etiologies of the observed association between red meat consumption and development of type 2 diabetes mellitus. Metabolism. 2015 Jul;64(7):768-79.
Muntoni S, Mereu R, Atzori L, Mereu A, Galassi S, Corda S, Frongia P, Angius E, Pusceddu P, Contu P, Cucca F, Congia M, Muntoni S. High meat consumption is associated with type 1 diabetes mellitus in a Sardinian case-control study. Acta Diabetol. 2013 Oct;50(5):713-9.
 Imamura F, O’Connor L, Ye Z, Mursu J, Hayashino Y, Bhupathiraju SN, ForouhiNG.Consumption of sugar sweetened beverages, artificially sweetened beverages, and fruit juice and incidence of type 2 diabetes: systematic review, meta-analysis, and estimation of population attributable fraction. BMJ. 2015 Jul 21;351:h3576.
 Lamb MM, Frederiksen B, Seifert JA, Kroehl M, Rewers M, Norris JM. Sugar intake is associated with progression from islet autoimmunity to type 1 diabetes: the Diabetes Autoimmunity Study in the Young. Diabetologia. 2015 Sep;58(9):2027-34.
DjousséL1, Gaziano JM, Buring JE, Lee IM. Egg consumption and risk of type 2 diabetes in men and women.Diabetes Care. 2009 Feb;32(2):295-300
McEvoy CT, Cardwell CR, Woodside JV, Young IS, Hunter SJ, McKinley MC.A posteriori dietary patterns are related to risk of type 2 diabetes: findings from a systematicreview and meta-analysis.J Acad Nutr Diet. 2014 Nov;114(11):1759-75.
 Karjalainen J, Martin JM, Knip M, Ilonen J, Robinson BH, Savilahti E, Akerblom HK, Dosch HM. A bovine albumin peptide as a possible trigger of insulin-dependent diabetes mellitus. N Engl J Med. 1992 Jul 30;327(5):302-7.
 Ishii H,Suzuki H, Baba T, Nakamura K, Watanabe T. Seasonal variation of glycemic control in type-2 diabetic patients. Diabetes Care 2001;24;1503.
 Colas C, Garabedian M, Fontbonne A, Guillozo H, Slama G, Desplanque N, Dauchy F, Tchobroutsky G. Insulin secretion and plasma 1,25(OH)2D after UV-B irradiation in healthy adults. Hormone and Metabolic Research 1988;21:154-155.
 Song Y, Wang L, Pittas AG, Del Gobbo LC, Zhang C, Manson JE, Hu FB. Blood 25-hydroxy vitamin D levels and incident type 2 diabetes: a meta-analysis of prospective studies. Diabetes Care. 2013 May;36(5):1422-8.
 Shore-Lorenti C, Brennan SL, Sanders KM, Neale RE, Lucas RM, EbelingPR.Shining the light on Sunshine: a systematic review of the influence of sun exposure on type 2 diabetes mellitus-related outcomes. Clin Endocrinol (Oxf). 2014 Dec;81(6):799-811.
Lindqvist PG, Olsson H, Landin-Olsson M. Are active sun exposure habits related to lowering risk of type 2 diabetes mellitus in women, a prospective cohort study? Diabetes Res Clin Pract. 2010 Oct;90(1):109-14.
By Marc Sorenson, EdD, for sun exposure…
A new research paper on sun exposure and cancer has some interesting observations and some errors. It is entitled, Does Sunlight protect us from cancer? Here is the abstract of the article, verbatim.
“The Ultraviolet (UV) radiation contained in sunlight is a powerful mutagen and immune suppressant which partly explains why exposure to solar UV is the biggest risk factor for the development of cutaneous tumors. Evidence is building that sunlight may be protective against some internal malignancies. Because patients with these tumors are often vitamin D deficient, this has led some to propose that vitamin D supplementation will be beneficial in the treatment of these cancers. However, the results from already completed trials have been disappointing which has given weight to the argument that there must be something else about sunlight that explains its cancer-protecting properties.”
The first sentence, of course, is false. The idea, that sun exposure is the biggest risk factor for skin cancer, is erroneous. We have presented materials many times, proving that melanoma is not caused by sun exposure, and that sun exposure is protective against that disease. And as regards common skin cancers, we have shown that high-fat nutrition, lack of antioxidants, meat consumption and alcohol intake are all risk factors. Search the blogs on this site to read the different articles.
The statement is correct, of course, that sunlight is protective against many internal cancers. Dr. Bill Grant and I are finishing our book, Embrace the Sun, where we present nearly all of the research on the protective influence of sun exposure against cancer.
The statement that vitamin D research has been disappointing is both true and false. Randomized controlled studies (RCTs) have shown the vitamin D supplements do have a protective effect against internal cancers, contrary to the statement by the researchers.
Finally, let’s look at the statement that there is something beyond vitamin D that explains the cancer-protecting properties of sun exposure. That is partially true. Beyond vitamin D, the sun causes the production of nitric oxide, serotonin, endorphin and BDNF, all of which are vital to human health, and may have their own cancer-protective properties.
The bottom line? Eat correctly (avoid junk), REGULARLY soak up some sun around midday and get plenty of exercise. That advice will be a boon to your health in myriad ways.
Sun and cognitive ability by Marc Sorenson, EdD, Sunlight Institute…
If you have depression, you may also have cognitive impairment, according to older research that I just became aware of. The researchers measured cognitive abilities among approximately 14,000 depressed subjects and then exposed them to either one day of sunlight or two weeks of sunlight. They then determined if cognitive disabilities were associated with the sun they obtained.
The results were impressive: Those who were sun-deprived for two weeks had 2.5 times the risk of being cognitively impaired, compared to those who had sufficient sunlight. A one-day exposure made no significant difference in cognition.
Results of other research, based on a 15-year residential history of varying degrees of sun exposure, has also shown that cognitive impairment in persons who were below the median exposure to sun, was 88% greater than those who were above the median. The researchers mentioned vitamin D as a possible mechanism by which sun positively influenced cognition, but they also remarked that regulation of the circadian rhythm by sunlight could be a factor.
Several other studies showed a close, positive association between vitamin D levels and cognition, and as we know, vitamin D levels in most cases are a surrogate measurement for sun exposure.
The message is to get plenty of sunlight to improve mental clarity. Happy thinking!
 Shia T Kent, Leslie A McClure, William L Crosson, Donna K Arnett, Virginia G Wadley and Nalini Sathiakumar. Effect of sunlight exposure on cognitive function among depressed and non-depressed participants: a REGARDS cross-sectional study. Environmental Health 2009, 8:34
 Kent ST, Kabagambe EK, Wadley VG, Howard VJ, Crosson WL, Al-Hamdan MZ, Judd SE, Peace F, McClure LA. The relationship between long-term sun radiation and cognitive decline in the REGARDS cohort study. Int J Biometeorol. 2014 Apr;58(3):361-70.
In a new scientific paper, Dr. MS Razzaque shows that there may be some downsides to vitamin D supplementation, including “cardiovascular events and beyond.” He also states that “since hypovitaminosis D status usually reflects reduced sunlight exposure, the obvious primary replacement should be safe sunlight exposure, and not exogenous supplements.”
The paper specifically mentions that avoiding sunlight exposure may influence the initiation and progression of different types of tumors [cancer], high blood pressure, type 1 diabetes and multiple sclerosis. It also points out that there may be some deleterious consequences of vitamin D supplementation, although in my opinion, the dosage would need to by quite high.
As I have indicated in many of my posts on the Sunlight Institute site, sun exposure is the most natural way to obtain vitamin D, and it has no toxicity, since it is self-regulated.
What wasn’t mentioned was the production of health-promoting substances when sun touches the skin, e.g. endorphins and nitric oxide. And of course, the sun helps the brain to produce serotonin and BDNF, which are critical for proper brain function.
So soak up your sunlight but don’t burn.
 Razzaque MS. Sunlight exposure: Do health benefits outweigh harm? J Steroid Biochem Mol Biol. 2016 Sep 16. [Epub ahead of print].
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…
In the previous blog, we noted that sun exposure was associated with a reduced risk of the deadly bacterial infection called sepsis. In reality, UV therapy was used to treat many kinds of infections decades ago, when sun exposure was widely known as a bactericide.
Dr. Zane Kime, in his book, Sunlight could Save Your Life, reviewed the results of research conducted between 1886 and 1909 and 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 along the bottom of the screen 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 [septicemia], 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.
The ancients knew of the marvelous healing effects of sun exposure, and Dr. Kime knew even more in 1980 as he reviewed the literature. We need more people who are willing to promulgate the truth about our kindly friend, the sun.
 Kime, Z. Sunlight Could Save Your Life. World Health Publications, Penryn, CA 1980 pp 180-81.
 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.
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 Sunlight Institute…
A most interesting research paper demonstrates that nitrate supplements, combined with exposure to sunlight, increases performance of cyclists. The researchers state that “dietary nitrate supplementation has been shown to increase nitric oxide (NO) metabolites, reduce blood pressure (BP) and enhance exercise performance.” And, as we have discussed in this blog, sun exposure reduces BP by increasing the production of NO. It was theorized that sun exposure might enhance the athletic performance induced by the dietary nitrate supplementation.
The theory proved to be correct; although sun exposure did not improve cycling times by itself, when combined with the nitrate supplementation, cycling times improved significantly.
It may surprise some people to realize that ultraviolet radiation (UVR) from sun beds or sun lamps has been used since before 1950 to enhance athletic performance. As early as 1938, Russian researchers reported that a course of UVR significantly improved speed in the 100-meter dash among four students when compared with controls that did not have the radiation, although both groups were undergoing identical daily training. The non-irradiated group improved by 1.7% but the irradiated group improved by 7.4%. Another study conducted over ten weeks showed that cardiovascular endurance improved remarkably among athletes in training who were irradiated vs. those who were not. The irradiated athletes improved by 19.2% compared to 1.5% among the non-irradiated group.
There are numerous studies from Germany showing the efficacy of UVR on athletic performance, most of them from the early days before the idea of sun-lamp produced UVR fell into disrepute because of the attack on tanning beds. What a shame. This method of athletic assistance could produce an impressive improvement in sports performance for so many people, athletic or not. Strength improves, stamina improves, quickness improves and speed improves with UVR radiation, which of course is also part of sunlight. The mechanism for this improvement is likely a combination of vitamin D and nitric oxide.
Safely enjoy the sun!
 Muggeridge DJ, Sculthorpe N, Grace FM, Willis G, Thornhill L, Weller RB, James PE, Easton C. Acute whole body UVA irradiation combined with nitrate ingestion enhances time trial performance in trained cyclists. Nitric Oxide. 2015 Aug 1;48:3-9.
 Cannell JJ, Hollis BW, Sorenson MB, Taft TN, Anderson JJ. Athletic performance and vitamin D. Med Sci Sports Exerc. 2009 May;41(5):1102-10.
 Gorkin Z. Gorkin MJ, Teslenko NE. The effect of ultraviolet radiation upon training for the 100-meter sprint.
 Allen R, Cureton T. Effects of ultraviolet radiation on physical fitness. Arch Phys Med 1945;10:641-4.