Are all vegetables okay to eat on a high protein diet?

It's the starchy and sugary carbs you have to avoid and corn and parsnips are high in starch. The other veg to watch out for are potatoes, carrots, corgettes and any others with a high amount of carbohydrate per serving. Of course grains aren't vegetables but rice, bread, etc are also high starch.

Take a look at the label and it will tell you the amount of carbohydrates per serving but if you stick to veg like broccoli, cauliflower, leeks, spinach, tamatoes (technically a fruit), peppers, asparagus, beans, etc, you'll be ok...