How long can a person live without food and water or air?

While you might die of thirst after three days without water, there are numerous reports of people lasting a week or longer. Several factors come into play, including weight, health, how much you exert yourself, temperature, and humidity. The record is supposedly 18 days, for a prisoner accidentally left in a holding cell. However, it's reported he may have licked condensation from the walls of his prison, which bought him some time.