Hiking equipment
According to Tom Brown, the basic plan for survival is in the order of shelter (including clothing), water, fire, and food. Cody Lundin writes about the "Rule of 3s"; this relates to human survival without basics: three minutes without air, three hours without shelter, three days without water, or three weeks without food.
Inedia
Some breatharians have submitted themselves to medical testing, including a hospital's observation of Indian mystic Prahlad Jani appearing to survive without food or water for 15 days, and an Israeli breatharian appearing to survive for eight days on a television documentary. In a handful of documented cases, individuals attempting breatharian fasting have died. Among the claims in support of Inedia investigated by the Indian Rationalist Association, all were found to be fraudulent. In other cases, people have attempted to survive on sunlight alone, only to abandon the effort after losing a large percentage of their body weight.