Just be firmly resolved not to eat the blood, because the blood is the life, and you must not eat the life with the flesh. - Deuteronomy 12:23
The Amish will not allow heart transplants and, in some cases, heart surgery because they view the heart as "the soul of the body." Children who have not been baptized are exempt from that restriction.
Hindus, Sikhs and Muslims
Vaishnavism, the major branch of the Hindu faith, considers the killing of animals, especially cows, to be sinful. Therefore, the religion does not condone the use of any drugs, implants, skin grafts or medical dressings that contain parts of pigs or bovines.
Christian Scientists believe that the primary method of healing should be through prayer, and many members have in the past been against modern medical treatments. There have been measles outbreaks among Christian Scientists, and studies have shown that mortality levels were high.