grains have fiber thats why they keep you regular. If the vegies arent itsprobably because you steam them. Try blending raw vegies up with some fruit juice and drink your raw vegies. (it tastes good also) I did a few Bowel Cleanses including Oxypowder but they dont work the only cleanse that worked for me was blessed herbs, I did it twice in 3 weeks and got out 30 foot of mucoid plaque. I need to do another soon.
Protien fish , red meat, chicken have almost zero fiber. Thats prob why you get constipated when you cut down on te carbs. If you are nursing I wouldnt be cutting down on the carbs I imagine you need all the energy you can get.
If you havent tried blessed herbs then give that a go. Also colonix is meant to be good.
Bile does help with constipation, a Liver Flush may help.