Excessive intake of omega six and falling omega three as a primary cause is my continued no 1 guess as a primary causal factor for rising rates (along with environmental factors lifestyle etc).
Omega six is the essential fuel for the eicosanoid omega six pathway.
I have very vague impressions that I have seen press reports poorer than avergae diet in Scotaland in terms of processed food etc. but would have to check.
Though provoking no matter what the cause.
RB
http://www.theherald.co.uk/news/63625.html