Well here's the one from the oxford journal : http://fampra.oxfordjournals.org/content/22/6/608.full.pdf
It's from 2005, but there have been several others since then. This one only found a 10% increase, but I recall other studies ranging as high as 35%. The effect is greater with more extreme chilling.
It's from 2005, but there have been several others since then. This one only found a 10% increase, but I recall other studies ranging as high as 35%. The effect is greater with more extreme chilling.