Cold Adaptation, BAT & Thermogenesis

Lerner posted a link to this study in comments on another post:  Cold-Activated Brown Adipose Tissue in Healthy Men.  A small part of the study where they looked at BAT activity for the three subjects with the most BAT under neutral thermal conditions caught my eye, and I think this is central to some of the confusion Kaptain Konfusion has introduced into this whole discussion.  They tested all subjects lying on their backs in a chamber, first for one hour in thermoneutral temp, next for 2 hours at 17C.  For three subjects they retested in thermoneutral temps for the entire time.  

There was no detectable brown-adipose-tissue activity in the three subjects who were retested under thermoneutral conditions. Brown-adipose-tissue activity was recorded in Subject 2 at 856.5 kBq during exposure to cold and 0 kBq in thermoneutral conditions, in Subject 3 at 587.2 kBq during cold exposure and 0 kBq in thermoneutral conditions, and in Subject 4 at 250.0 kBq during cold exposure and 0 kBq thermoneutral conditions.

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