Sorry, but for most women, pregnancy = water retention
Focus on keeping ANY real food down that you can. IMO staying hydrated and nourished is more important than sticking to a particular way of eating. If all you can keep down is grains and dairy, then rock that out until you feel better!
Plus, you'll most likely only deal with the morning sickness and nausea for the first three months, and then you'll be back in the game.
For what it's worth,
I had extreme all-day sickness for the first six months of my pregnancy...and all I could keep down was dry cereal and peanut butter sandwiches. Really.
Since the six month mark when my nausea finally went away, I've been able to get completely back on track with healthy eating.
"Imagine all the people, living life in peace..."
"Nothing will work unless you do."