Final answer:
Chewing with your mouth open is considered crude because it is seen as poor manners in many cultures. Additionally, it exposes the mouth to microbes that can lead to dental and other health issues. Thus, it is beneficial for both social and health reasons to chew with the mouth closed.
Step-by-step explanation:
Chewing with your mouth open is often considered crude due to social etiquette standards and health reasons. In many cultures, principled habits related to eating, such as keeping your mouth closed when chewing, is a sign of respect and good manners. Furthermore, this practice is also integral to maintaining health and hygiene. The oral cavity plays a fundamental role in our digestive system.
When we chew, our food gets mixed with saliva which aids in breaking it down for digestion. The act of chewing with an open mouth can, however, expose us to microbes that can potentially harm our teeth and instigate infections. Some of these infections have the potential to spread beyond the mouth and affect other areas of our body, leading to serious health concerns.
In essence, not only is chewing with an open mouth socially inappropriate – due to cultural standards of manners and etiquette – it's also potentially harmful to our health. Thus, it is in our best interest to chew with our mouths closed, aiding in both our social and physical well-being.
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