By Marc Sorenson, EdD, Sunlight Institute
Serotonin is one of the most potent natural mood enhancers produced in the body. As previously mentioned in one of my blogs, men whose levels of serotonin were measured on a very bright day produced eight times more serotonin than those who were measured on a cloudy, dismal day. Serotonin levels were also seven times higher in summer than winter.[1] Serotonin works in concert with melatonin; serotonin keeps keeps us bright and happy during the sunny day and melatonin lets lets us sleep during the dark night. Unfortunately, lack of sunlight in winter may also lead to too much daytime melatonin production, which may lead to aggressive behavior.
A 2015 report from Proceedings of the Royal Academy B, demonstrated that female rats who had the least sunlight exposure per day displayed the most aggression.[2] A similar increase in aggression was not observed in male rats.
An increase in melatonin was given as the reason for the aggression, since when winter approaches, sunlight decreases and melatonin increases. (Of course, serotonin also decreases, as stated in the aforementioned research.) Melatonin increases aggression, according to this study, by acting on the adrenal glands, causing a release of a hormone called DHEA, which has been consistently been linked to aggression in both mammals and birds.
I’m not entirely convinced that that aggression was not caused more by the drop in serotonin than the increase in melatonin. Either way, you boyfriends and husbands should be sure that your lady love gets plenty of sunlight or other form of UV light every day of the year, or you may be in trouble!
[1] Lambert GW, Reid C, Kaye DM, Jennings GL, Esler MD. Effect of sunlight and season on serotonin turnover in the brain. Lancet. 2002 Dec 7;360(9348):1840-2.
[2] Proceedings of the Royal Academy B 2015. Reported by Carly St. James, Empire State News. http://www.empirestatenews.net/2015/11/19/a-spike-in-female-aggression-can-be-linked-to-this-seasonal-change/ [accessed November 19, 2015]}
By Marc Sorenson, EdD, Sunlight Institute…..
Before proceeding with the discussion on sunlight addiction, it is important to review the truth about sunlight and melanoma, to understand why sunlight addiction may be a good thing.
A recent report on ultraviolet light and addiction[1] is obviously meant to be a hit piece regarding sunlight exposure and tanning, as seen in the opening statement: “Despite widespread awareness that UV exposure is a major risk factor for all common cutaneous malignancies, skin cancer incidence relentlessly increases by ~3% per year.”
The “all common cutaneous malignancies” portion of this statement, of course, is patently false. Whereas the relatively benign common skin cancers are increased by exposure to sunlight, melanoma is increased by avoiding the sun. If the dramatic increase in melanoma over the past century were due to sunlight exposure, then sunlight exposure must also have increased dramatically during that time. To determine whether that has happened, we analyzed data from the Office of Occupational Statistics and Employment Projections, Bureau of Labor Statistics, (BLS) to determine if there was an increase or decrease in human sunlight exposure during the years from 1910 to 2,000.[2] The statistics showed that indoor occupations such as “professional, managerial, clerical, sales, and service workers grew from one-quarter to three-quarters of total employment between 1910 and 2000.” BLS also stated that during the same period, the outdoor occupation of farming declined from 33% to 1.2% of total employment, a 96% reduction. The data also showed an approximately 66% decline in the occupation of farmers and 50% of the decline in the occupation of farm laborers.
The Environmental Protection Agency also determined that as of 1986, about 5 percent of adult men worked mostly outside, and that about 10 percent worked outside part of the time. The proportion of women who worked outside was thought to be even lower.[3] These data demonstrate a dramatic shift from outdoor, sun-exposed activity to indoor, non-sun-exposed activity during the mid-to-late 20th Century.
Despite these facts, the Melanoma International Foundation (MIF) has stated that melanoma has increased by 30 times (3,000%) just since 1935! Here is the statement by the MIF: “Melanoma is epidemic: rising faster than any other cancer and projected to affect one person in 50 by 2010, currently it affects 1 in 75. In 1935, only one in 1,500 was struck by the disease.”[4] Indeed, the American Cancer Society in 2014 reported that one in 50 now contracts the disease.[5] That exponential increase in melanoma has been accompanied by a profound decrease in sunlight exposure, yet sunlight or other UV exposure is blamed for the melanoma increase—a totally counterintuitive argument! I submit that not only is sunlight not responsible for the exponential increase in melanoma, but that the decrease in sun exposure may be a major cause of that increase.
Here are other facts that belie the idea that melanoma is caused by sunlight exposure:
- Outdoor workers, while receiving 3-9 times the UVR exposure as indoor workers,[6] [7] have had no increase in melanoma since before 1940, whereas melanoma incidence in indoor workers has increased steadily and exponentially.
- Most melanomas occur on areas of the body that are seldom or never exposed to the sunlight.[8] [9] [10]
- The use of sunscreen, which has increased steadily, has not resulted in a decrease in melanoma.[11] In fact, melanoma has increased as sunscreen use has become more widespread. Since sunscreens block sunlight, it is evident that at best they are a waste of money and at worst may be contributing to the increase in melanoma.
Now, let’s discuss the research on the aforementioned addiction to sunlight. The researchers conducted various experiments on mice that showed behavior choices, such as desiring lighter rather than darker environments, were increased by regular exposure. These behavior choices were mediated by β-endorphins, peptide hormones which are similar to opiates. So is this all bad? This marvelous product, β-endorphin, is one of the feel-good hormones that decreases pain and increases a sense of well-being. The case the researchers make regarding addiction to sunlight is compelling, and why not? Sunlight exposure causes vitamin D production in the skin, which is essential to human health; it also stimulates the production of nitric oxide, which relaxes our vessels and lowers our blood pressure; it stimulates the production of serotonin in the brain, which is another feel-good hormone necessary for a happy mood and wellbeing. And considering the myriad additional effects of sunlight on health, including the prevention of cancer, the prevention and reversal of bone diseases and the reduction of heart disease, could it not be part of God’s (or Nature’s) master plan to develop a positive addiction to sunlight so than our health could be enhanced? I am a sunlight addict, and expose myself to it regularly for two reasons: (1) It marvelously improves my mood and (2) it protects me from disease and weakness. I am a light-skinned, blue-eyed Caucasian who has spent much of my seven decades on this earth seeking the sun. Yet, there have been no melanomas or even common skin cancer.
Nevertheless, the researchers summarize their paper on sun addiction with the following: “While primordial UV addiction, mediated by the hedonic [pertaining to pleasure] action of β-endorphin and anhedonic effects of withdrawal, may theoretically have enhanced evolutionary vitamin D biosynthesis, it now may contribute to the relentless rise in skin cancer incidence in man.”
That summary statement is claptrap, as can be seen by the research on melanoma and sunlight presented above. If sunlight is addictive and helps me to avoid melanoma, heart disease, bone loss and other maladies, I can only say, “hooray for the addiction!”
[1] Gillian L. Fell, Kathleen C. Robinson, Jianren Mao, Clifford J. Woolf, and David E.
Fisher. Skin β-endorphin mediates addiction to ultraviolet light. Cell. 2014 June 19; 157(7): 1527–1534.
[2] 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
[3] U.S. Congress, Office of Technology Assessment, Catching Our Breath: Next Steps for Reducing Urban Ozone, OTA-O-412 (Washington, DC: U.S. Government Printing Office, July 1989).
[4] Melanoma International Foundation, 2007 Facts about melanoma. Sources: National Cancer Institute 2007 SEER Database, American Cancer Society’s 2007 Facts and Figures, The Skin Cancer Foundation, The American Academy of Dermatology.
[5] American Cancer Society. Melanoma Skin Cancer Overview 9/16/2014. Accessed on 9/23/2014 at http://www.cancer.org/cancer/skincancer-melanoma/overviewguide/melanoma-skin-cancer-overview-key-statistics
[6] Godar D. UV doses worldwide. Photochem Photobiol 2005;81:736–49.
[7] 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.
[8] 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.
[9] Rivers, J. Is there more than one road to melanoma? Lancet 2004;363:728-30.
[10] Crombie, I. Racial differences in melanoma incidence. Br J Cancer 1979;40:185-93.
[11] Phillippe Autier. Do high factor Sunscreens offer protection from melanoma? West J Med. 2000 Jul; 173(1): 58.
By Marc Sorenson, EdD, Sunlight Institute
In a new media release from Toronto, the Vitamin D Society asserts that “The importance of natural sunlight to human life cannot be understated.” It goes on to quote Dr. Reinhold Vieth, a scientist and professor at the University of Toronto. “There really is no substitute for natural sunlight in human health. Your skin is like a solar receptor and has the amazing capacity to manufacture all of the vitamin D your body needs. Everyone has the capability to generate vitamin D.”
There is a problem, however, as I posted recently. About a third of Canadians, about 12 million people, do not meet the minimum Health Canada guidelines for vitamin D levels. The reason? Sunlight deficiency.
Perry Holman, executive director of the Society, states that “This is not a call for people to ignore the warnings about over-exposure to sunlight but a call for people to exercise common sense and ensure they are not shutting themselves out from the vital health benefits of natural sunlight.”
Of course, in the winter, when no vitamin D production is available, it will be necessary to find another source of vitamin-D stimulating light. Sunlamps are ideal, provided they produce UVB light.
Also remember, that during winter, sunlight still raises serotonin levels and produces nitric oxide, both of which are necessary to human health. The value of sunlight goes far beyond its ability to promote vitamin D production in the skin.
For more information on the Vitamin D Society, visit www.vitamindsociety.org.
We have discussed the extraordinary ability of sunlight exposure or other bright-light exposure to profoundly increase the production of serotonin, a brain chemical that is a potent mood enhancer. The most remarkable research on this subject was by Dr. Gavin Lambert and his colleagues in Australia. They measured serotonin levels in response to varying degrees of bright light.[1] To do this, they actually took blood samples from internal jugular veins of 101 men and compared the serotonin concentration of the blood to weather conditions and seasons. The results were remarkable: MEN WHO WERE MEASURED ON A VERY BRIGHT DAY PRODUCED EIGHT TIMES MORE SEROTONIN THAN THOSE WHO WERE MEASURED ON A CLOUDY, DISMAL DAY. They also observed that the effect of bright light was immediate, and that there was no holdover from day to day. SEROTONIN LEVELS WERE ALSO SEVEN TIMES HIGHER IN SUMMER THAN WINTER. NO WONDER WE FEEL SO GOOD WHEN WE ARE OUTSIDE IN THE SUMMERTIME!
The most popular anti-depressant drugs also work by keeping serotonin levels higher, but there are frightening side-effects. The Food and Drug Administration (FDA), indicates that antidepressant medications known as selective serotonin re-uptake inhibitors (SSRI’s) may increase depression in some cases and lead to suicidal thoughts. Some of the brands involved are Paxil, Lexapro, Prozac, Effexor, Zoloft, Wellbutrin, Luvox, Celexa and Serzone, although the FDA listed 34 drugs. The entire list is at fda.gov/cder/drug/antidepressants/. They state the following: “The Food and Drug Administration asks manufacturers of all antidepressant drugs to include in their labeling a boxed warning and expanded warning statements that alert health care providers to an increased risk of suicidality in children and adolescents being treated with these agents, and additional information about the results of pediatric studies.”
The FDA lists several additional warnings and instructions about these drugs:
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Antidepressants increase the risk of suicidal thinking and behavior (suicidality) in children and adolescents with MDD (major depressive disorder) and other psychiatric disorders.
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Anyone considering the use of an antidepressant in a child or adolescent for any clinical use must balance the risk of increased suicidality with the clinical need.
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Patients who are started on therapy should be observed closely for clinical worsening, suicidality, or unusual changes in behavior.
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Families should be advised to closely observe the patient and to communicate with the prescriber.
Missing are two important facts: (1) SSRI’s increase bone loss.[2] Women who used SSRI’s lose nearly 80% more bone per year than non-users! And as expected, later research shows that SSRI use correlated to a 75% greater likelihood of sustaining a fracture.[3] Secondly, SSRI’s don’t work very well. A meta-analysis of data on SSRI’s submitted to the FDA indicates that placebos (sugar pills) are as effective as SSRI’s in reducing depression; [4] in other words, only drug companies benefit from SSRI’s—not depression sufferers.
Based on that information, it seems prudent to increase our endorphins (and our happiness) through sunlight exposure. It is what nature intended.
[1] Lambert GW, Reid C, Kaye DM, Jennings GL, Esler MD. Effect of sunlight and season on serotonin turnover in the brain. Lancet. 2002 Dec 7;360(9348):1840-2.
[2] Diem SJ, Blackwell TL, Stone KL, Yaffe K, Haney EM, Bliziotes MM, Ensrud KE.. Use of antidepressants and rates of hip bone loss in older women; the study of osteoporotic fractures. Arch Intern Med 2007:167:1231-32.
[3] Sheu YH, Lanteigne A, Stürmer T, Pate V, Azrael D, Miller M5. SSRI use and risk of fractures among perimenopausal women without mental disorders. Inj Prev. 2015 Jun 25. pii: injuryprev-2014-041483. doi: 10.1136/injuryprev-2014-041483. [Epub ahead of print]
[4] Kirsch, I. et al. Initial severity and antidepressant benefits: a meta-analysis of data submitted to the Food and Drug Administration. PLoS Medicine 2008;5:e45. doi:10.1371/journal.pmed.0050045
By Marc Sorenson, EdD
Drs. Asta Juzeniene and Johan Moan wrote a paper in 2012 that beautifully summarizes the effects of sunlight beyond the production of vitamin D.[1] Here are the highlights of their paper, as stated in the abstract. They discuss the separate affects of Ultraviolet B light (UVB) and ultraviolet A light (UVA), which are, of course, components of sunlight.
- UVB induces cosmetic tanning (immediate pigment darkening, persistent pigment darkening and delayed tanning).
- UVB-induced, delayed tanning acts as a sunscreen.
- Several human skin diseases, like psoriasis, vitiligo, atopic dermatitis and localized scleroderma, can be treated with sunlight or artificial UV radiation (phototherapy).
- UV exposure can suppresses multiple sclerosis independently of vitamin D synthesis.
- UVA generates nitric oxide (NO), which may reduce blood pressure and generally improve cardiovascular health.
- UVA induced NO may also have antimicrobial effects.
- UVA induced NO may act as a neurotransmitter.
- UV exposure may improve mood through the release of endorphin.
It wasn’t mentioned in the paper, but we now know that sunlight also helps generate serotonin in the brain, which improves mood, and outside the body it is a potent disinfectant (see my recent blogs on those subjects). So those who claim that sunlight is harmful in any amount, must be living on a different planet. Embrace the Sun, but never burn.
[1] Asta Juzeniene and Johan Moan. Beneficial effects of UV radiation other than via vitamin D production. Dermato-Endocrinology 4:2, 109–117; April/May/June 2012.