Also per my above post - the type of weight changes you are talking about are miniscule compared to a true "problem" - I know it is a relative thing, and when eating what is perceived as a "clean" or "good" diet (without really designing it specifically and intentionally for what the goal is), thyroid always seems to be a first place to place blame. Just to be realistic (also granted that thyroid issues are also a bit hard to really identify w/o actually getting the testing done) here is a list of the typical symptoms of hyper or hypo (full article:
http://thyroid.about.com/cs/basics_starthere/a/symptoms.htm) -
Symptoms of Hypothyroidism (An underactive thyroid)
fatigue, exhaustion
feeling run down and sluggish
depression
difficulty concentrating, brain fog
unexplained or excessive weight gain
dry, coarse and/or itchy skin
dry, coarse and/or thinning hair
feeling cold, especially in the extremities
constipation
muscle cramps
increased menstrual flow
more frequent periods
infertility/miscarriage
Symptoms of Hyperthryodisim (An overactive thyroid)
nervousness
irritability
increased perspiration
thinning of your skin
fine brittle hair
muscular weakness especially involving the upper arms and thighs
shaky hands
panic disorder
insomnia
racing heart
more frequent bowel movements
weight loss despite a good appetite
lighter flow, less frequent menstrual periods
Like Bunny notes and all of us have experienced in one form or another - start w/ diet. And not just "I eat clean". Really dissect the diet and go from there.