Health benefits of UV by Marc Sorenson, Ed.D.
How important is UV? 
A transcendentally important scientific paper, by Dr. AT Slominski and colleagues, has added significant information about UV (sunlight) for skin. In addition, it explains the intricate connection between sunlight and the immune, endocrine and central nervous systems.[1] The name of the research paper, published in the journal Endocrinology, is How ultraviolet light touches the brain and endocrine system through skin, and why. The authors begin the abstract by stating that “the skin is a self-regulating protective barrier organ that is empowered with sensory and computing capabilities to counteract the environmental stressors to maintain/restore disrupted cutaneous homeostasis.” In other words, the skin has the ability to take on what life deals it and maintain its equilibrium and balance. In addition, the skin communicates bidirectionally with the central nervous, endocrine and immune systems. Thus, it helps to maintain balance for all body systems.
How does UV work?
First of all, ultraviolet energy (UV and UVB light) triggers all of these marvelous processes. UV, of course is available from sunlight, sunbeds or sunlamps. Its electromagnetic energy, through the skin, converts to chemical, hormonal and neural signals. These signals promote positive effects on the immune system, the endocrine system and the brain. Furthermore, endorphins (opioid-like substances) are increased and immune-system proteins are mobilized; consequently, health improves with UV. And, sun exposure regulates the endocrine system, by way of exposure to the skin, to produce or diminish hormones as needed. Especially relevant is that these effects take place independently of vitamin D synthesis.
Health increases with UV due to the magnificent sun, and our magnificent skin. As a result of the above information, it seems like it would be a good idea to soak up some non-burning sun each day when available. And, when it is not, we should find another UV source. In our soon-to-be-published book, Embrace the Sun, we discuss many facts about the healthful effects sun exposure:
A few healthful effects of sun (UV) exposure
- prevents and reverses obesity
- Improves longevity by reducing the risk of death by 50% over 20 years
- reduces the risk of hip fracture by 90% when compared to sun avoidance
- prevents the risk of breast cancer by 90% when compared to sun avoidance
- reduces by 50% the risk of melanoma in outdoor workers compared with indoor workers
- increases heart and vascular strength
- dramatically improves mood
- reduces the risk of multiple sclerosis
- reduces risk of most internal cancers
- cures psoriasis and eczema
- reduces risk of nervous system disorders
- prevents memory loss
- prevents myopia
The above list is not surprising in view of this new research, nor is the list complete. UV has many more healthful effects, which I’m sure the authors of this research acknowledge. Hence, the scientists sum up their research in this manner: “Thus, UV touches the brain and central neuroendocrine system to reset body homeostasis. This invites multiple therapeutic applications of UV radiation, for example in the management of autoimmune and mood disorders, addiction, and obesity.”
In conclusion, this seem like more compelling evidence to safely embrace the sun, no?
[1] Slominski AT, Zmijewski MA, Plonka PM, Szaflarski JP, Paus R. How ultraviolet light touches the brain and endocrine system through skin, and why. Endocrinology. 2018 Mar 12. [Epub ahead of print]
By Marc Sorenson, EdD, Sunlight Institute
Are you suffering from anxiety disorder, but fear taking drugs? Your fear is well-founded. It has been shown that a class of drugs called anti-anxiety drugs, i.e. valium and Xanax, and sleep aids like Ambien, Sonata and Lunesta lead to increased risk of death.[i] During 7.6 years, and after controlling for other factors such as sleep disorders, anxiety disorders and other psychiatric illnesses, it was found that the risk of dying was 3.46 times higher in those who took the drugs compared to those who did not. Considering the material we have posted on this site regarding brain disorders, insomnia, and sunlight, it seems reasonable to believe that a better and less dangerous anxiety-treatment option would be regular sunlight exposure.
Research from Denmark has shown that morning light, made to mimic daylight, relieves anxiety by reducing the activity of the brain’s fear center.[ii] The efficacy of the light treatment was based on the intensity of the light: the greater intensity, the greater the effect.
Another scientist, Dr Klaus Martiny, commented on the above study and noted that morning light improves sleep. “A lack of daylight disrupts some hormonal processes in our body that regulate our circadian rhythm. This can result in a shift in circadian rhythm, so that people go to sleep later and later in the evenings, and this shift is associated with an increased risk of depression.”[iii]
Martiny suggested that a good rule of thumb is to go to sleep before midnight and awaken before 8:00 AM. However, we discussed in the post on obesity that the earliest morning sunlight was associated with a remarkably lessened risk of obesity, which was also attributed to resetting the circadian rhythm. We therefore suggest that a better rule of thumb is to be outside for a half-hour when the sun rises each morning.
Get your morning sunlight, your midday sunlight and your afternoon sunlight. Sunlight is the great healer.
[i] Weich S, Pearce H, Croft P, Singh S, Crome L. et al. Effect of anxiolytic and hypnotic drug prescriptions on mortality hazards: retrospective cohort study. BMJ 2014;348:g1996.
[ii] Christensen B. Morning light relieves anxiety. Science Nordic 2014. http://sciencenordic.com/morning-light-relieves-anxiety Accessed August 8, 2015.
[iii] http://sciencenordic.com/morning-light-relieves-anxiety. Accessed August 8, 2015
By Marc Sorenson, EdD Sunlight Institute
We have previously discussed information indicating that people who received more sunlight had better brain function, and noted the relationship between Alzheimer’s, autism and other mental disorders and lack of sun. A recent study compared cognitive impairment and sunlight in a 15-year residential history of varying degrees of sunlight exposure. It showed that cognitive impairment in persons who were below the median exposure to sunlight was 88% greater than those who were above the median.[1]
The researchers mentioned vitamin D as a possible mechanism by which sunlight positively influenced cognition, but also remarked that regulation of the circadian rhythm by sunlight could be a factor. These same investigators had previously shown that lower levels of sunlight exposure resulted in a 2.58-times higher incidence of cognitive impairment.[2]
So, if you would like to maintain your cognitive abilities, soak up a little non-burning sunlight!
[1] Kent ST, Kabagambe EK, Wadley VG, Howard VJ, Crosson WL, Al-Hamdan MZ, Judd SE, Peace F, McClure LA. The relationship between long-term sunlight radiation and cognitive decline in the REGARDS cohort study. Int J Biometeorol. 2014 Apr;58(3):361-70.
[2] Kent ST, McClure LA, Crosson WL, Arnett DK, Wadley VG, Sathiakumar N. Effect of sunlight exposure on cognitive function among depressed and non-depressed participants: a REGARDS cross-sectional study. Environ Health. 2009 Jul 28;8:34
Marc Sorenson, EdD, Sunlight Institute.
Anything that causes arterial plugging or prevents the relaxation of blood vessels can contribute to cardiovascular diseases (CVD). Poor diet, little exercise and lack of sunlight exposure form a combination that devastates vessel health and reduces the flexibility of those vessels. Among the CVD are ischemic heart disease, intermittent claudication (painful oxygen restriction to the legs), ischemia of the brain leading to strokes, peripheral artery disease and erectile dysfunction. Yes, I said erectile dysfunction.
ED is considered one of the major predictors of CVD.[i] It is caused by inability of the corpus cavernosa, two cylindrical chambers that run the length of the penis, to become engorged with blood, causing erection. When the process takes place normally, the cavernosa are stimulated by nitric oxide (NO), they then relax, and blood flows into the penis, allowing erection to take place. Therefore, erection is a vascular event.[ii] The same effect is seen in blood pressure decreases caused by NO after sunlight exposure. Ultraviolet A (UVA) light stimulation of the skin causes the release of NO from pre-formed stores of NO in the skin. NO is a potent vasodilator, and when it is released into the arteries by UVA stimulation, causes increased blood flow and lowers blood pressure.[iii] The mechanism is much the same in both instances. This is another example of sunlight enhancing health without the benefit of vitamin D. UVA light, that stimulates nitric oxide release, does not stimulate the skin to produce vitamin D.
An early study assessed the affect of ultraviolet light (UV) exposure to cavernosal strips, which were obtained from men during penile prosthetic surgery.[iv] The strips showed relaxation in response to UV, and the relaxation increased with the duration of exposure. We expect that sunbathing, which would profoundly increase NO in the circulation, would also vasodilate the cavernosa to allow erection. The same nitric oxide mechanism that lowers blood pressure, would seem to be a good method to treat ED. After all, drugs for ED, such as Viagra and Cialis, work by enhancing the effects of nitric oxide.[v] Sunlight is free and is a much better choice.
[i] Pastuszak AW, Hyman DA, Yadav N, Godoy G, Lipshultz LI, Araujo AB, Khera M. Erectile dysfunction as a marker for cardiovascular disease diagnosis and intervention: a cost analysis. J Sex Med 2015 Apr;12(4):975-84.
[ii] Marc Sorenson and William B. Grant. Does vitamin D deficiency contribute to erectile dysfunction? Dermatoendocrinol 2012 Apr 1; 4(2): 128–136.
[iii] Liu D, Fernandez BO, Hamilton A, Lang NN, Gallagher JM, Newby DE, Feelisch M, Weller RB. UVA irradiation of human skin vasodilates arterial vasculature and lowers blood pressure independently of nitric oxide synthase. J Invest Dermatol. 2014 Jul;134(7):1839-46.
[iv] Kim SC, Oh CH, Park JK, Lee MY, Uhm DY. Effects of ultraviolet light on the tension of isolated human cavernosal smooth muscle from non-diabetic and diabetic impotent men. Urol Res. 1997;25(2):149-52.
[v] Mayo Clinic Online. http://www.mayoclinic.org/diseases-conditions/erectile-dysfunction/in-depth/erectile-dysfunction/art-20047821. Accessed July 3, 2015.