Gemara:


Ein Ayah: The foundation of haughtiness is that one removes his heart from the realization that that which is good for him is not up to him. Rather, any possible shleimut comes from His Hand, which should cause a person not to be so proud about that which is not his own. Palpable feeling will not be able to imagine this, because the senses will not sense something that is outside the one who is feeling. Therefore, one who is drawn in by his senses will make a haughty connection and say that he saved himself.
In contrast the goal of prayer is to engrain in the heart the realization that all the good we have comes from Hashem. Therefore, one should involve himself in prayer, which brings him humility, before eating, which brings on blind haughtiness.