Short background: For my two previous pregnancies, I ate SAD and was almost completely sedentary. For both, I failed the 1-hour glucose test miserably. I barely passed the 3-hour in both pregnancies. I was diagnosed prediabetic after birth of my second kid. Shortly after I discovered Primal/Paleo.
This third pregnancy I am older (GD risk increases with age). I've been eating mostly primal, but not low-carb. I do eat white potatoes, rice on some occasions, and dairy. I stay away from wheat and other grains, and refined sugar. I also walk 3 miles per day (at a snail's pace... but it's something).
And I passed my 1-hour glucose tolerance test with "excellent numbers" (according to my doc). I was so shocked I asked them to double-check my results.
So was it Primal that did it? The extra exercise? The fact that I'm not eating a McDonald's value meal (extra large!) with soda most nights of the week?
I think it was a combination of all those things. So any pregnant ladies out there: Primal *can* help you avoid gestational diabetes!