>An unexplained weight gain of about 5 lbs has me reaching for possible
hormonal explanations to account for > the sudden onset of bloat (mostly
round the stomach and associated with the puffiness that shrieks fluid
build-> up.)

> Dairy foods, such as milk, cheese, yoghurt (which I have recently added to
my diet, despite not being paleo) > might also be in the frame. What do
others think?

Yogurt is high on the insulin index
http://venus.nildram.co.uk/veganmc/insulin.htm .  High insulin can cause
inflammation (puffiness...).

Rob