Food and drink have direct effect on our health. That is why Islam has prescribed regulations about our food and drink. It lays great emphasis on our physical as well as moral health, because both of these are equally important for a healthy society. The abstention from eating pork is one of the steps taken by Islam to practise hygiene and to attain purity of soul.
Islam, for the cultivation of inner faculties, insists upon the cleanliness of body and the purification of soul through Salaat (prayers) Zikr (remembrance of Allah) and other devotional duties. Islam teaches us how to attain the virtues and how to give up bad habits because both good and bad grow in the man according to his upbringing, education and environment.
A human being has natural desires: food, sleep and sex being the three primary ones. He has also other natural emotions: sorrow, happiness, love, fear, disgust and avarice etc. Islam doesn't recommend the complete abrogation of these impulses but offers a method of controlling them through religious education and discipline.
The prohibition of eating pork in Islam is relevant in this context. There is a saying in English that "a man becomes what he eats." According to physicians and medical experts, pork is a harmful diet. Consumption of swine-flesh creates lowliness in character and destroys moral and spiritual faculties in a man.