Sunshine is good for you and good for fighting all cancers including skin cancer! by Dr Chris Barnes, Bangor Scientific and Educational Consultants http://drchrisbarnes.co.uk January 2015 ( revised December 2015) email firstname.lastname@example.org
The study shows by way of geographic meta-analysis that sunshine, presumably as a source of vitamin D3 is far more beneficial at fighting/preventing all cancers including melanoma than previously acknowledged and could potentially prevent up to 20% of cancers in general even some melanoma. The only possible causative factors which appear to correlate melanoma incidence positively in the present study are sunbed use and radon gas concentration.
We have heard so much misinterpreted news in the media about cancer recently, I couldn’t resist making an investigation using one of the biggest established cancer cohorts in the world, see http://statecancerprofiles.cancer.gov/ . Two statements recently one by Dr Richard Smith, a UK doctor, and one by a US research group could, potentially and in my personal opinion set cancer research back decades and we should not allow this to happen. First is Smith in the UK that says Cancer is a good way to die  and we should give up treating people. I watched my mother-in-law die of cancer and I can assure Dr Smith he wouldn’t wish the same on himself. Second is the US research group including Tomaseeti and Vogelstein whose ‘test tube’ stem cell study suggests cancer is all down to chance . Well human being are not ‘test tubes’ and yes they may have the chance of inheriting faulty tumour repair and suppressor genes but mutations aren’t just down to chance they are also down to being hit by radiation or mutagens. Oh and to cap it all I get frustrated when I hear both fellow academics and news media alike described how bad the sun is and advising that if you slap on the sunscreen you will be fine. This is because recently, I established just the contrary, i.e. namely that people with lack of sun (low serum vitamin D status) may be at extra risk of certain types of cancer. For example, it is well known the Black and Asian women living in cold ,cloudy climates such as the UK suffer from more ‘triple negative’ breast cancer than those living in warmer, sunnier areas .
The hypothesis I propose is simplicity itself: if sunshine viz a viz ultraviolet production of D3 is really beneficial as a cancer prophylactic this ought to show in a geographic metal analysis.
I will be investigating an entire cancer cohort by both traditional linear regression analyses and by geographic mapping visual comparisons (human eye based meta-analysis.
The data pertaining to US cancers is all available at http://statecancerprofiles.cancer.gov/ , with the exception of total incidence for the state of Nevada which was obtained from http://www.foxnews.com/health/2012/10/29/nevada-has-higher-cancer-rates-than-neighboring-states/ .
The data pertaining to percentage sunshine is available at
Solar u/v mapping is from ‘AVGLO’ , see also Tatalovitch .
A straight linear regression of total cancer incidence rates state by state against annual percentage sunshine was made. Then a visual meta-analysis of the geographic mapping of total cancer incidence rate and solar u/v was attempted.
Results and Discussion
The linear regression result is shown below, see figure 1
Figure 1 : Cancer Incidence versus total sunshine
A negative linear correlation is observed, regression coefficient 0.68. The most aberrant single point or largest residual is that at 41% total sunshine which is for the state of Alaska, where cancer rates are apparently lower than predicted by the sunshine algorithm.
Alaska has significantly less radon and significantly less pesticide use than mainland USA.
This result is highly significant. A regression coefficient of .68 is enormous in epidemiology terms considering that say the coefficient for smoking and cancer is of the order of 0.02. My P Value Results r=.68 DF=20 yield s two-tailed P value equals 0.0005
By conventional criteria, this difference is considered to be extremely statistically significant.
In other words sunlight is extremely good for us. Vitamin D does far more than protect us from rickets. It is a powerful antioxidant, and increases anti-inflammatory cytokine and has great potential as an anti- cancer agent, see for example Trump et al (2004)  and many others.
Furthermore, since melatonin derives from serotonin, see B Claustrat (1984)  , the more exposure to natural light we get the better is the serotonin to melatonin balance in the brain and the more able is the body to ramp up melatonin levels at night also needed for cancer protection.
Results ( mapping)
In figure 2, the solar u/v map and the cancer incidence map have purposely been placed side by side. In the solar u/v map dark blue represents least u/v and red is most. In the cancer incidence map, dark blue represents most cancer and white least.
The visual result of this meta analysis is blindingly striking.
The Inference from both the regression and the mapping analysis is that maybe 20% of cancers could be prevented (possibly cured) by sunshine alone (vitamin D!!!!!!!!)
But what about melanoma skin cancer
I have produced a similar correlation, see figure 3.
On the face of it, the correlation regression coefficient is zero or close to zero. Actually it is +.03.
Close inspection of the function tends to suggest there are other factors at play here. For example, when a quadratic fit is applied it can be seen that at very low and very high percentage sunshine the rate seems significantly lower.
Only geographic mapping meta-analysis can properly explain what is happening. One such study has previously been done, see http://www.jaad.org/cms/attachment/2005408035/2023469760/gr1.jpg
but for some reason the authors ignored several states in the USA.
I have included all the data and a very different story emerges, see Figure 5.
I have compared the geographic distribution of melanoma, solar u/v and radon gas in the USA. A far stronger correlation can be seen between radon gas and melanoma than solar u/v.
This is wholly in line with the results of my recent UK analysis. Also in that study I came to the conclusion that sun in spring and autumn gave protection from melanoma due to higher u/v in summer.
It is also interesting to note that in 5 out of the 9 states with the worst melanoma incidence there are no restrictions on the teenage use of sun tanning parlours. Sun beds are reckoned to be dangerous because of the different balance of u/v A to u/v B compared with natural sunlight furthermore they expose the user to high electric and magnetic fields in themselves potential carcinogens.
Based on the above statistics, sun is far better for us than previously thought and could potentially prevent up to 20% of cancers in general even some melanoma. The mechanism may be maintenance of adequate serum vitamin D3 but also even the maintenance of adequate melatonin. Sun bed use and living in high radon gas areas are potentially the greatest risks for melanoma cancer and living in areas with greater than about 72% annual sunshine may actually be protective against melanoma, contrary to all traditionally established expectations.
10. B Claustrat, G Chazot, J Brun, D Jordan, G Sassolas - Biol Psychiatry, 1984 - gwern.net