Is plain cooked millet safer or better for my cat than white rice?

Both plain cooked millet and white rice are safe for cats in small, occasional amounts, but they have different profiles. Millet is gluten-free and offers some different minerals, while white rice is often easier to digest for a cat with a temporarily upset stomach. Neither is a necessary part of a cat's diet, as they are obligate carnivores. The main thing is to offer either one cooked plain, without any butter, salt, or seasonings. If you're using it to settle her stomach, a spoonful of either is fine, but watch for any new digestive issues.