Though science has yet to explain fully the exact reason for why do we yawn. It has been able to answer the question that, why do eyes water when we yawn. When your eyes tear, that doesn't mean you have serious health issues or disorders. Infact, it protects eyes from drying, so it's good to cry. Though some people have more notable tearing of eyes than others. It is very usual. Still if you a very concerned, I hope this article will clear your doubt on this.
Well, we all yawn when we feel bored or tired. This makes our body take less oxygen and we breathe slowly, so yawning help us to bring more oxygen in the body and exhale out more carbon dioxide out of blood.
Yes, our eyes start tearing when we yawn. But why? It's because the pressure created on the lacrimal glands which are situated on the upper side of the top of our eyes.
The tiny black dot on our lower eyelid which is also called punctum closes when we squeeze our eyelids tightly which makes tears drain from tear duct.