One of the first known references to hunger strikes dates back to medieval Ireland, whose civil code regulated their use as a means to redress an injustice. The wronged person would fast on the doorstep of the offender. If the hunger striker died, the householder -- beside suffering great dishonor -- was held responsible and had to pay compensation to his family.
India had a similar practice, which was abolished by the British-run government in 1861.
One of the world's most famous hunger strikers, Bobby Sands, was from Northern Ireland. He was one of 10 Irish republicans who starved to death in British jails to protest detention conditions.
"I'm continually wrapped up in blankets, but find it hard to keep my feet warm," Sands wrote in his diary on the 16th day of his hunger strike. "It doesn't help my body temperature, drinking pints of cold water. I'm still able to take the salt and five or six pints of water per day without too much discomfort."
Deprived of food, the body uses fat reserves for the first three weeks before drawing on muscles and vital organs for energy. Hunger strikers rarely survive beyond 70 days. Sands died after 66 days.
New, less grueling types of hunger strikes have emerged in recent years. One of them is the "relay" hunger strike, in which protesters hold consecutive 24-hour fasts over an extended period of time.