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Increased sunlight exposure means decreased prostate cancer.
How much do sunlight and vitamin D help to
prevent prostate cancer?
In 2005, Dr. Esther John and colleagues
reported on research in which they compared the lifetime sun
exposure of 450 men with advanced prostate cancer with that
of 455 men who did not have cancer.[1]
The men were divided into five groups
(quintiles) according to the amount of sun exposure they had
received.
The results were impressive.
The men in the highest quintile (fifth) of
sun exposure had only 51% of the risk of prostate cancer as
did those in the lowest quintile.
Several other studies have shown that high
sun exposure over a lifetime relates to a considerably lower
rate of death from prostate cancer.[2] [3] [4] [5]
The last study[5] showed that those who
were born in a state with high solar radiation had a reduced
risk of 49%.
Perhaps the most impressive research
studies were done by Dr. S Moon and colleagues where they
compared sunlight exposure and prostate cancer risk.[6]
The subjects in two of studies were
divided into four groups (quartiles) according to the
lifetime sunlight exposure they had received.
Those in the lowest quartile of
sunlight exposure had more than three times the risk of
developing prostate cancer as those in the highest quartile.
Dr. Moon’s group noted that when
sunbathing was compared with prostate cancer, men in the
lowest exposure quartile (fourth) of sunbathing had 5.33
times the risk of prostate cancer as those in the highest
quartile.
Sunbathing is obviously a great habit for
men, provided it isn’t overdone. Other research has
indicated that “higher levels of cumulative exposure, adult
sunbathing, childhood sunburning and regular holidays in hot
climates were each independently and significantly
associated with a reduced risk of this cancer.”[7]
Nevertheless, it is always best to avoid
sunburn.
Can there be any doubt that sunlight and
vitamin D are essential to a good prostate health?
[1] John, E. et al. sun exposure, vitamin
D receptor polymorphisms and risk of advanced prostate
cancer. Cancer Res 2005;65:5479.
[2] Freedman, D. et al. sunlight and
mortality from breast, ovarian, colon, prostate and
non-melanoma skin cancer: a composite death certificate
based case-control study. Occup environ Med 2002;59:257-62.
[3]Hanchette, C. et al. Geographic
patterns of prostate cancer mortality: Evidence for a
protective effect of ultraviolet radiation. Cancer
1992;70:2861-69
[4] Schwartz, G. et al. Is vitamin D deficiency a risk
factor for prostate cancer? [hypothesis] Anticancer Res
1990;10:1307-11.
[5] John, E. et al. Residential sunlight
exposure is associated with a decreased risk of prostate
cancer. J Steroid Biochem Mol Biol 2004;89:-90.
[6] Moon, S. et al. Ultraviolet radiation:
effects on risks of prostate and other internal cancers.
Mutat Res 2005; 571:207–219.
[7] Bodiwala, D. et al. Prostate cancer
risk and exposure to ultraviolet radiation: further support
for the protective effect of sunlight. Cancer Lett
2003;192:145-49.
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