Islam provides guidance for a pure and healthy life. God says in the Holy Quran,
“He has made unlawful to you only that which dies of itself, and blood, and the flesh of swine, and that on which the name of any other than Allah has been invoked. But he who is driven by necessity, being neither disobedient nor exceeding the limit, it shall be no sin for him. Surely, Allah is Most Forgiving, Merciful.” (Quran 2:173-174)
The first three categories are prohibited because they are harmful to the body, and that which is harmful to the body is harmful to the spirit. The last prohibition relates to something which is directly harmful morally and spiritually, as it amounts to association of others with God. Allah has made the provision that a believer may use prohibited food if absolutely necessary; i.e., if it is a matter of life and death.
There are two terms “halal” and “tayyeb” used in The Holy Quran to guide about foods. The term halal means “that which is lawful for you”; thus halal meat is that which has been slaughtered in the name of Allah, and has had the blood drained out from it. Sometimes some foods are not permitted by the laws of the countries, so even a “halal” item may become under the not permitted category. The term “tayyeb” means pure, wholesome and acquired by legal and ethical means. The Holy Quran lays a great emphasis on this aspect of food as well. Foods which are decayed or spoiled are forbidden. The term “haram” means that which is unlawful for you, and includes blood, pork and alcohol.
Islam teaches that the condition of the body affects the condition of the spirit, and thus great care should be taken to keep one’s body healthy and fit. Islam further teaches that all food should be taken in moderation, and nothing should be indulged into excess. Furthermore intoxicants and drugs are forbidden. Any food which becomes addictive, enters in the category of forbidden category.