Sunlight/vitamin D re health

[Guest guest]

The Int J Epidemiol 2006 35(2) issue is:

http://ije.oxfordjournals.org/current.dtl

and has several paper commenting on the association of sunlight/vitamin D on our

health. This is presented as an overview in the below, and pdfs are available

for

this overview and the other related papers in this issue of the journal.

GEORGE DAVEY SMITH http://ije.oxfordjournals.org/current.dtl

Cultural climate, physical climate, life, and death

Int J Epidemiol 2006 35(2):211-212

http://ije.oxfordjournals.org/cgi/content/extract/35/2/211

... The effect of climate on health is the focus of our ‘reprint and

reflections’ and several of our original papers. In 1980 the IJE published the

first

major hypothesis paper on the apparent protective effect of sunlight on colon

cancer, which we reprint in this issue.24 Based on the simple use of routine

data

Cedric and Garland showed that within the US there was an inverse

association

between sunlight and colon cancer mortality and hypothesized that this was due

to a

protective effect of vitamin D on colon cancer. Since then, as our commentators

discuss,15,25–29 much further research has been carried out on the vitamin

D–colon

cancer link, and a major contributor to this literature, Giovannucci,

concludes that the evidence is ‘fairly compelling’ that sunlight and vitamin D

are

protective.30 One of the original authors, together with colleagues, now expands

the

hypothesis to suggest that sunlight and vitamin D have protective effects on

various

cancers, and mechanisms for the protective effects are discussed by Heide

Cross.2–7

Climate is seen as a less salubrious exposure by Cheng et al.,31 who show

that

extreme weather events in northern Australia are linked to clusters of

melioidosis

caused by pathogens with diverse DNA patterns. Jordi Sunyer and Joan Grimalt

suggest

that globally the influence of climate change will be to increase health

inequalities between rich and poor nations and rich and poor people.32 But what

about the long-term health consequences of climate during the intrauterine

period

and birth? Although there has been discussion of this for nearly a century, the

study by Sophie et al.33 from the Gambia showing increased mortality risk

across life in those born during the wet season, rekindled interest in this area

and

led to speculation about possible immune system modulation as the mechanism.

Using

data from Burkina Faso, Gisela Kynast-Wolf et al.34 fail to replicate this

finding

and in her commentary Sophie 35 reviews current thinking about this issue.

....

-- Al Pater, alpater@...

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