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.
Henry S. Tanner (doctor)
Because no one believed his claim that he had fasted for 42 days, in January 1880, Tanner, a practitioner of hygienic medicine, announced that he would repeat his experiment to show that humans can survive without food and would agree to submit himself to be placed “under the care of any medical society” that would provide adequate housing. On June 30, Tanner began his attempt to duplicate his 40-day fast and after the 6th day, the New York Times began a series of articles chronicling his day –to-day progress, each dispatch becoming more ominous in its anticipation that his death by starvation was imminent. As the twelfth night approached, a Times headline announced that “The End [was] Predicted to be at Hand”. But rather than deteriorating, by the twentieth day, Tanner’s condition improved and he “looked and acted better than ever”.