I can't eat grains or starches. How do I get more fibre in my diet?

I’m on a month-long diet to stabilize my blood sugar due to hypoglycemia by eliminating starches and grains. On top of that, I can’t eat dairy, soy, gluten or sugar (long story—basically, I’m allergic). So I can only eat meat, veggies, some fruits, nuts and legumes (even though beans give me gas!), I think. Am I missing a food group? Anyways, I’m afraid I’m going to lose weight from my diet restrictions (I’m already quite thin) and really need more fibre.

Any recipe tips or general help you can provide? I don’t know anyone with this kind of restriction on their diet who can help.