I have coeliac disease so need to be gluten free. I've been told to watch out for my fibre intake so eat extra fruits and vegetables.
Some sauces tend to contain gluten as well. I like to make everything from scratch because of this. Be wary of some stock cubes.
Potatoes and rice are naturally gluten free. It is a lot cheaper to buy gluten free flour and just do a massive bulk bake, such pancakes, cereal bars, biscuits, bread etc. The pricing is stupid.