Why are creamed soups not allowed on a gluten-free diet?

Creamed soups are often made using a roux, which is a mixture of flour and fat used to thicken soups and sauces. Since traditional flour contains gluten, which is a protein found in wheat and certain other grains, any soup made with flour would not be suitable for someone adhering to a gluten-free diet. This dietary restriction is essential for individuals with celiac disease or gluten intolerance, as consuming gluten can lead to adverse health effects.

While the other options touch on aspects that could be true of creamed soups, such as being high in calories, made with dairy, or highly processed, they do not directly address the fundamental concern of gluten content. Therefore, the reason that creamed soups are not allowed on a gluten-free diet specifically relates to their common ingredient of flour, making it the most pertinent answer.