Are you drinking any soda?
Soda beverages and other carbonated drinks are acidic with a pH of 3.0 or less.
In an attempt to keep your bodys blood pH from becoming too acidic, it uses its stored supplies of iodine to neutralize that acid.
This iodine is no longer able to be used by your thyroid which in turn slows down your metabolism
Ian, is this because of the carbonation? I got a home carbonator and love to make my own seltzer...