Which of the following is considered a common allergen that should be noted on menus?

Gluten is widely recognized as a common allergen that affects a significant portion of the population, particularly those with celiac disease or gluten sensitivity. It is a protein found in wheat, barley, and rye, and can lead to various health issues for individuals who are intolerant to it. Because of the prevalence of gluten intolerance and the necessity for affected individuals to avoid gluten in their diets, it is essential for food establishments to clearly indicate the presence of gluten on menus. This awareness helps ensure that customers with dietary restrictions can make informed choices regarding their food selections, thus enhancing their dining experience.

In contrast, while red meat, corn, and rice can cause reactions in some individuals, they are not categorized as common allergens subjected to the same level of scrutiny or legal requirements for disclosure as gluten. Owing to this context, gluten is particularly important to note for those with specific dietary concerns.