Here is a vid of what can happen if you eat too much sugar for your metabolism (and yes that is whole grains, whole grain pasta has a very similar GI rating as coke or straight sugar... starch is broken down into sugar quickly.. drinking a coke has about the same sugar spike as eating whole bran cereal)
http://www.youtube.com/watch?v=mNYlIcXynwE
if you don't have that issue no you won't have that problem. Pregnancy makes it worse.
I will have you know I ate 'healthy' by all common methods, low fat low junk high in complex carbs and exercised.. and GAINED weight. And its not uncommon! but I am lying so what ever...
I think you and I have very much the same type of metabolism, Kerri.
Within days after I cut gluten out of my diet -- which meant most of the carbs considered healthy as I rarely ate any grain based foods that weren't whole grain -- all the puffiness started to melt away and I've slowly but surely been getting visibly smaller.
As long as I kept it simple and didn't mess with making gluten free breads of any sort, pastas, etc. and didn't eat any rice or other "white food" (except dairy) it was not only steady but appeared to be moving along at an increasing rate.
When I added gluten free substitutes I slowed down again.
It's the same pattern I saw when bodybuilding: stick to high protein, very limited carbs, some fats and I built muscle and melted body fat. Add carbs -- and I was doing it in an EXTREMELY healthy way -- and POOF, there went the definition and the weight started going up, and it wasn't muscle.
Oh, and cholesterol, triglycerides and all those nasties? Mine were laughably low and the good cholesterol was in the upper ranges.
NOT EVERY METHOD WORKS FOR EVERY PERSON. PERIOD.