In a previous post, I mentioned that morning sunlight exposure correlated to a lower body-mass index (BMI), a measurement which is used to assess whether a person is obese, normal weight, overweight, etc.[1] It was obvious that production of vitamin D was not the mechanism that led to the slimmer bodies, because D production is greatest at midday.
The relationship of weight to sunlight has again been assessed in an impressive animal study. The researchers fed mice a high-fat diet to investigate the effects of vitamin D and/or ultraviolet radiation (UVR) (such as that in sunlight) on the potential to develop obesity, diabetes and other measures—a cluster of maladies known as the metabolic syndrome (MetS). Long-term UVR exposure significantly suppressed weight gain, glucose intolerance, insulin resistance, and fatty liver disease. It also suppressed blood levels of fasting insulin, glucose and cholesterol.[2] Interestingly, those benefits were not reproducible by vitamin D supplementation. However, when nitric oxide (NO) was increased by UVR exposure, many of the positive benefits were indeed duplicated.
The authors make a profound statement to conclude their research: “These studies suggest that UVR (sunlight exposure) may be an effective means of suppressing the development of obesity and MetS, through mechanisms that are independent of vitamin D but dependent on other UVR-induced mediators such as NO.”
The takeaway from this research is that we cannot simply throw a vitamin D capsule at a problem and expect it to take the place of the sun. That marvelous hormone, vitamin D, is critically important to human health, and the information here does not denigrate its importance; nevertheless, there are many other important sunlight products such as NO, serotonin, and endorphins that are essential to wellbeing. We need them all, and sunlight is the best source.
Stay slim and stay healthy by enjoying safe, non-burning sunlight.
[1] S.p://sunlightinstitute.org/morning-sunlight-may-lead-slimmer-figure
[2] Geldenhuys S, Hart PH, Endersby R, Jacoby P, Feelisch M, Weller RB, Matthews V, Gorman S. Ultraviolet radiation suppresses obesity and symptoms of metabolic syndrome independently of vitamin D in mice fed a high-fat diet. Diabetes. 2014 Nov;63(11):3759-69.
More than two years ago I read of ongoing research by Dr. Pelle Lindqvist—reasearch indicating that greater exposure to sunlight resulted in longer life. I made several attempts to contact Dr. Lindqvist, but was unsuccessful. However, one of his colleagues answered my query and informed me that the research would not be completed later on and then be published. The results are now available, and they are impressive.[1]
During a 20-year period, the subjects in the study who avoided sun exposure were twice as likely to die of any cause compared to those who had the highest sun exposure, and the researchers made this statement: “In both models the summary sun exposure variables showed a ‘dose-dependent’ inverse relation between sun exposure and all-cause death.”
Sunlight exposure has been shown to correlate to a reduced risk of numerous cancers, including non-Hodgkin’s lymphoma, but results with Hodgkin’s lymphoma (HL) are mixed. The most recent research shows that there is an inverse correlation between HL and the highest vs. lowest lifetime, childhood and adulthood experience with the following three factors: sunlight exposure, sun-lamp exposure, and sunburn. [1] The pooled analysis showed an odds ratio of .56, or in other words, a 44% reduced risk of contracting the disease.
Two items particularly stand out in this research: (1) Sun-lamp use correlated to a reduced risk of the disease—a positive result for the much maligned tanning industry—and (2) sunburn also correlated to a reduced risk. Of course, no one would recommend sun-burning; it simply serves a surrogate measurement for a high degree of sunlight exposure. Sunlight exposure can easily be used in high quantities—without burning—by moving out of the sun when the skin begins to redden and then coming back later after the skin has adjusted and started to tan.
This research once again points out the efficacy of sunlight in reducing cancer. Don’t expect the American Academy of Dermatology to mention this vital information in their next newsletter!
[1] Monnereau A, Glaser SL, Schupp CW, Ekström Smedby K, de Sanjosé S, et al. Exposure to UV radiation and risk of Hodgkin lymphoma: a pooled analysis. Blood 2013;122(20):3492-9
An article on the ABC website[1] poses the following question: “If sun exposure causes skin cancers, how is it that some skin cancers grow in body parts that never see the light of day?” It then follows up by listing several areas where skin cancers occur: “Between the toes, on the soles of the feet, even around the genitals … skin cancers can appear on body parts that rarely or never see the sun.”
They then quote the CEO from Cancer Council Australia, Professor Ian Oliver, who tells us that the sun’s ultraviolet light (UVR) is by far and away the major cause of skin cancers. If he is talking about melanoma, he is dead wrong. And if he is talking about common skin cancers, how many of those cancers are found in or on the aforementioned areas of the body? This is a misguided effort to “frighten the daylights out of the people to frighten them out of the daylight” as said Dr. Michael Holick, a great vitamin D researcher.
Let’s make it clear that this effort is aimed at melanoma, the deadly skin cancer that does indeed occur in areas that are seldom or never exposed to sunlight. To say that UVR (sun exposure) is far and away the major cause of skin cancer (melanoma) is simply untrue. Mr. Oliver is not a liar, but he has obviously not read the research. He is terribly misguided if he believes that sunlight is the causal factor in the disease. Let’s look at the facts:
Sunlight exposure dramatically decreased in the US during the 20th Century, and Melanoma increased by at least 30-fold during that time.[2] Concomitantly, the percentage of outdoor workers, those most likely to be exposed to sunlight, decreased dramatically; for example, the outdoor occupation of farming decreased from 33% to 1.2% of total employment[3], a 96% reduction. Further information from the EPA determined that as of 1986, about 5 percent of adult men worked mostly outdoors, and that about 10 percent worked outside part of the time. The proportion of women who worked outside was thought to be lower. It becomes quite obvious that as sunlight exposure has profoundly decreased, the risk of melanoma has skyrocketed.
Furthermore, other research demonstrates that outdoor workers, while receiving 3-9 times the sunlight exposure as indoor workers, have had no increase in melanoma since 1940, whereas melanoma incidence in indoor workers has increased exponentially.[4] [5] From that information, one could reasonably conclude that regular, outdoor sunlight exposure protects against melanoma. There are at least a dozen more studies in the professional literature that corroborate that those who live indoors have far more melanoma than those who live outdoors.[6]
If sunlight exposure is the reason for the increase in melanoma, we would expect that areas of the body that receive the most exposure would also be the areas of greatest occurrence of the disease. Mr. Oliver believes that this is the case, but it is not. As to the distribution of melanomas in “unexpected” areas, the scientific literature points out that there are higher rates on the trunk (seldom exposed to sunlight) than on the head and arms (commonly exposed to sunlight).[7] Others research demonstrates that melanomas in women occur primarily on the upper legs, and in men more frequently on the back—areas of little sunlight exposure.[8] In African Americans, melanoma is more common on the soles of the feet and on the lower legs, where exposure to sunlight is almost non-existent.[9] According to these facts, if there is a relationship between sunlight exposure and melanoma, the relationship is inverse—the greater the exposure, the less the risk of melanoma.
For more information on this subject, see my earlier blog: Exposing-sunlightmelanoma-fraud-part-1
My hope is that you will learn the facts presented here and become a good soldier in the battle to protect the Sun, our greatest friend.
[2] Melanoma International Foundation, 2007 Facts about melanoma.
[3] Ian D. Wyatt and Daniel E. Hecker. Occupational changes in the 20th century. Monthly Labor Review, March 2006 pp 35-57: Office of Occupational Statistics and Employment Projections, Bureau of Labor Statistics.
[4] Godar DE, Landry RJ, Lucas AD. Increased UVA exposures and decreased cutaneous Vitamin D3 levels may be responsible for the increasing incidence of melanoma. Med hypothesis (2009), doi:10.1016/j.mehy.2008.09.056 –
[5] Godar D. UV doses worldwide. Photochem Photobiol 2005;81:736–49.
[6] Lee J. Melanoma and exposure to sunlight. Epidemiol Rev 1982;4:110–36.
Vågero D, Ringbäck G, Kiviranta H. Melanoma and other tumors of the skin among office, other indoor and outdoor workers in Sweden 1961–1979 Brit J Cancer 1986;53:507–12.
Kennedy C, Bajdik CD, Willemze R, De Gruijl FR, Bouwes Bavinck JN; Leiden Skin Cancer Study. The influence of painful sunburns and lifetime sun exposure on the risk of actinic keratoses, seborrheic warts, melanocytic nevi, atypical nevi, and skin cancer. Invest Dermatol 2003;120:1087–93.
Garland FC, White MR, Garland CF, Shaw E, Gorham ED. Occupational sunlight exposure and melanoma in the USA Navy. Arch Environ Health 1990; 45:261-67. Kaskel P, Sander S, Kron M, Kind P, Peter RU, Krähn G. Outdoor activities in childhood: a protective factor for cutaneous melanoma? Results of a case-control study in 271 matched pairs. Br J Dermatol 2001;145:602-09.
Garsaud P, Boisseau-Garsaud AM, Ossondo M, Azaloux H, Escanmant P, Le Mab G. Epidemiology of cutaneous melanoma in the French West Indies (Martinique). Am J Epidemiol 1998;147:66-8.
Le Marchand l, Saltzman S, Hankin JH, Wilkens LR, Franke SJM, Kolonel N. Sun exposure, diet and melanoma in Hawaii Caucasians. Am J Epidemiol 2006;164:232-45.
Armstong K, Kricker A. The epidemiology of UV induced skin cancer. J Photochem Biol 2001;63:8-18
Crombie IK. Distribution of malignant melanoma on the body surface. Br J Cancer 1981;43:842-9.
Crombie IK. Variation of melanoma incidence with latitude in North America and Europe. Br J Cancer 1979;40:774-81.
Weinstock MA, Colditz,BA, Willett WC, Stampfer MJ. Bronstein, BR, Speizer FE. Nonfamilial cutaneous melanoma incidence in women associated with sun exposure before 20 years of age. Pediatrics 1989;84:199-204.
Tucker MA, Goldstein AM. Melanoma etiology: where are we? Oncogene 20f03;22:3042-52.
Berwick M, Armstrong BK, Ben-Porat L, Fine J, Kricker A, Eberle C. Sun exposure and mortality from melanoma. J Nat Cancer Inst 2005;97:95-199.
Veierød MB, Weiderpass E, Thörn M, Hansson J, Lund E, Armstrong B. A prospective study of pigmentation, sun exposure, and risk of cutaneous malignant melanoma in women. J Natl Cancer Inst 2003;95:1530-8.
Oliveria SA, Saraiya M, Geller AC, Heneghan MK, Jorgensen C. Sun exposure and risk of melanoma. Arch Dis Child 2006;91:131-8.
Elwood JM, Gallagher RP, Hill GB, Pearson JCG. Cutaneous melanoma in relation to intermittent and constant sun exposure—the western Canada melanoma study. Int J Cancer 2006;35:427-33
[7] Garland FC, White MR, Garland CF, Shaw E, Gorham ED. Occupational sunlight exposure and melanoma in the USA Navy. Arch Environ Health 1990; 45:261-67.
[8] Rivers, J. Is there more than one road to melanoma? Lancet 2004;363:728-30.
[9] Crombie, I. Racial differences in melanoma incidence. Br J Cancer 1979;40:185-93.
From Science Daily, research is reported on the ability of sunlight exposure to effectively lower blood pressure.[i] The research, reported earlier by Dr. Richard Weller, is not really new, but it is good to see that it is receiving more press. Even more important is the fact that Dr. Weller is a dermatologist. The study was conducted by exposing the skin of 24 healthy volunteers to ultraviolet light from tanning lamps for two sessions of 20 minutes each. In one session, they were exposed to both ultraviolet A (UVA) and the heat from the lamps; in another, the UVA rays were blocked so that only the heat was applied. Blood pressure was lowered by UVA exposure, but not by heat alone.
It has been known for some time that nitric oxide (NO) is produced by the skin in response to sunlight. NO is a potent vasodilator that relaxes the vessels and allows blood pressure to drop. Therefore, the sunlight, or tanning lamps, both of which emit UBA, become useful tools for lowering blood pressure.
It is important to note that these results were achieved with no increase in vitamin D levels. Therefore, sunlight stands on its own in reducing blood pressure. This is not to negate the positive influence of vitamin D; it is a critical factor in reducing the risk of myriad diseases. My ongoing searches of the medical and scientific literature, however, have persuaded me that most studies that assess the influence of sunlight alone are more impressive in preventing disease than those that assess only vitamin D blood levels or supplementation.
Dr. Feelisch, one of the investigators, stated the following: “These results are significant to the ongoing debate about potential health benefits of sunlight and the role of Vitamin D in this process. It may be an opportune time to reassess the risks and benefits of sunlight for human health and to take a fresh look at current public health advice. Avoiding excess sunlight exposure is critical to prevent skin cancer, but not being exposed to it at all, out of fear or as a result of a certain lifestyle, could increase the risk of cardiovascular disease.”
More on this subject will follow. In the meantime, allow yourself safe, non-burning exposure to the sun.
[i] University of Southampton (2014, January 17). Here comes the sun to lower your blood pressure. Science Daily. Retrieved January 18, 2014, from http://www.sciencedaily.com /releases/2014/01/140117090139.htm.
In the last post, I made the point that sunlight, through the stimulation of nitric oxide (NO) production in the skin, created a vasodilating effect in healthy volunteers that led to lower blood pressure. It was also noted that the effect of sunlight on blood pressure was not due to vitamin D production and circulation, since there was no change in vitamin D levels during the investigation.
High blood pressure is also known as hypertension, and a recent study from China demonstrates that exposure to sunlight correlates to a lowered risk of that disease.[1] In a randomly selected population of Chinese residents from Macau (where the rate of hypertension is very high), the following risk factors for hypertension were assessed: lack of sunlight exposure, low intake of fish, smoking, obesity and lack of exercise. An average of more than one-half hour of sunlight exposure per day compared to none predicted a 40% reduced risk for hypertension. Oily fish consumption more than four times per week predicted a 60% reduced risk; daily moderate physical activity compared to no physical activity predicted a 20% reduced risk; being obese compared to normal weight predicted 4.6 times the risk of hypertension, and heavy smoking predicted 1.4 times the risk.
Hypertension is a major risk factor for heart and other vascular diseases, which are the number-one killers in western societies. Isn’t it time we made a few lifestyle changes that could profoundly reduce the risk of these diseases? The efforts to Frighten people out of the sunlight, coupled with the move to indoor living, have created unquestionable health disasters. We need to once again learn to enjoy safe, non-burning sun exposure.
[1] Ke L, Ho J, Feng J, Mpofu E, Dibley MJ, Feng X et al. Modifiable risk factors including sunlight exposure and fish consumption are associated with risk of hypertension in a large representative population from Macau. J Steroid Biochem Mol Biol 2013 Nov 1 [Epub ahead of print].
Is sunlight the best disinfectant? Through serendipity, I happened on an article called Natural Alternatives to Bleach for Disinfecting.[1] It discussed pros and cons of such disinfectants as bleach, vinegar, hydrogen peroxide and yes, sunlight. The article stated that bleach could be dangerous, causing irritation to the eyes, mouth, lungs and skin, and when mixed with ammonia could result in the release of toxic fumes.
The authors suggested three alternatives: vinegar, which is non-toxic, hydrogen peroxide, which can cause burns at high concentrations, but when used safely is reasonably safe, and sunlight, which like vinegar is nontoxic. The article states “In fact, scientists have found that exposing a bottle of water to sunlight for 6 hours is an economical way to provide developing countries with safe drinking water (see References 2). The disinfecting properties of sunlight can also be useful around the house. If you have an object that you can move outside, the sun’s rays can help disinfect it. A stained piece of white laundry can be effectively brightened and disinfected by spraying the stain with lemon juice or vinegar and then hanging it in the sun.”
Imagine that—no wonder my mother hung her clothes out on a line in the summer sun to dry, although I don’t recall any use of vinegar or lemon juice.
The mention of water also took me back a few years to the time I spent a week with a Mexican friend of mine in a small town near Guadalajara called Juchipila. As most of you know, the drinking water in Mexico is often contaminated with noxious bacteria, and the sale of bottled water to prevent “Montezuma’s revenge” is big business. While there, my friend Miguel and I visited a bottled-water plant. Interestingly, the only method of purification was the exposure of the water to ultraviolet light. It obviously did a terrific job, because the proprietor did a good business with no reported problems of related bacterial diseases.
There was a time when sunlight was used to disinfect hospitals, and such should be the case now, considering the superbugs that have developed a resistance to antibiotics. The legendary humanitarian Florence Nightingale observed that sunlight helped heal wounded soldiers and insisted that hospitals be constructed to allow the free entry of sunlight.[2]
In reality, it has long been known that sunlight is a powerful disinfectant and bactericide. As early as 1877, researchers discovered that sugar water left in the shade became cloudy, indicative of bacterial growth, but if exposed to sunlight, it remained clear.[3] In 1890, the German microbiologist Robert Koch (who had isolated and described the tuberculosis bacterium in 1882), showed that sunlight killed TB bacteria.[4] Later on, research showed sunlight also killed E. coli bacteria in twelve feet of seawater and in waste stabilization ponds.[5] [6] [7]
In the aforementioned article comparing alternative disinfectants with bleach, the authors mentioned that exposing the armpits to sunlight would kill the bacteria that caused odor. There is little that I enjoy more than sunbathing with my hands behind my head and my armpits exposed to the sun. Lots of vitamin D, nitric oxide and endorphins produced, and later on I am more popular with my friends!
Sunlight exposure has been shown to heal Tuberculosis, psoriasis and a host of other diseases. To protect against a multitude of diseases, infectious and otherwise, be sure that you and your environment are exposed to plenty of sunlight, but also be sure not to burn. Any reddening of the skin indicates that you have had enough.
[1] http://homeguides.sfgate.com/natural-alternatives-bleach-disinfecting-79312.html
[2] Nightingale, F. Notes on Hospitals (third edition) Longman, Roberts and Green 1863.
[3] Downes, A. Researches on the effect of light upon bacteria and other organisms. Proc Roy Soc Med 1877;26:488.
[4] Hobday, R. The Healing sun. Findhorn Press 1999:132.
[5] Hart, D. Sterilization of the air in the operating room by special antibacterial radiant energy. J Thorac Cardiovasc Surg 1936;6:45.
[6] Gameson, A. et al. Field studies on effect of daylight on mortality of coliform bacteria. Water Res 1967;1:279.70.
[7] Calkins, J. et al. The role of solar ultraviolet radiation in natural water purification. Photochem Photobiol 1976;24:49.
Several studies have shown the efficacy of vitamin D in reducing fractures of various kinds. Stress fractures caused by physical training among military recruits is 3.6 times higher in those whose vitamin D levels are low compared to those whose levels are in “normal” ranges.[iii] Women in Spain who are continually seeking the sun have about one-eleventh the risk of hip fractures as those who have little sunlight exposure.[iv] It has also been proved several times by a Japanese physician, Dr. Sato that sunlight exposure can halt brittle bones and profoundly reduce the risk of hip fracture in women who already suffer from osteoporosis.[v]
Sunlight is necessary for stimulating the production of vitamin D in the skin, and vitamin D is absolutely essential for the absorption of calcium in the gut and for the maintenance of calcium stores in the bones to prevent bone diseases. One investigation showed that when serum levels of vitamin D increased from an average of 20 ng/ml to 34.6 ng/ml, calcium absorption increased by 65%, and the risk of hip, wrist, forearm or vertebral fracture was reduced by 33%.[vi] My opinion is that vitamin D levels should be between 60 and 70 ng/ml. Had that level been achieved in the subjects, it is likely that fractures risk would have been decreased more impressively.
We don’t know what Anderson’s serum levels of vitamin are, but he should find out. If they are low, he may be able to heal his injuries much faster by doing a lot of sunbathing.
[ii] Harris SS, Dawson-Hughes B. Seasonal changes in plasma 25-hydroxyvitamin D concentrations of young American black and white women. Am J Clin Nutr 1998;67:1232-36
[iii] Ruohola JP, Laaksi I, Ylikomi T, Haataja R, Mattila VM, Sahi T, Tuohimaa P, Pihlajamäki H. Association between serum 25(OH0d concentrations and bone stress fractures in Finnish young men. J Bone Miner Res 2006;21:1483-88.
[iv] Larrosa, M. Vitamin D deficiency and related factors in patients with osteoporotic hip fracture. Med Clin (BARC) 2008;130:6-9.
[v]¨Sato, Y. et al. Amelioration of osteoporosis and hypovitaminosis D by sunlight exposure in stroke patients. Neurology2003;61:338-42.
[vi] Heaney RP, Dowell MS, Hale CA, Bendich A. Calcium Absorption Varies within the Reference Range for Serum 25-Hydroxyvitamin D. J Am Coll Nutr 2003;22:142-46.d