In contrast to starvation with access to liquids, much more is known about survival without any sustenance (neither food nor hydration), which is a far more important practical consideration in medicine and ethics. This situation comes up frequently in two distinct medical groups--the incompetent terminally ill patients for whom artificial maintenance of life is no longer desired, and the individuals who, although not necessarily terminally ill, no longer want to live and decide to refuse food and hydration to end their lives.

A well-known example of the former is Nancy Cruzan, the subject of the famous 1990 U.S. Supreme Court decision in Cruzan versus Director, Missouri Department of Health. Cruzan was in a persistent vegetative state (PVS) for many years until she died 12 days after artificial sustenance was discontinued. Since that time, many other incidences of discontinuing sustenance in patients in a PVS have been reported and death typically occurs after 10 to 14 days. (If the individual is dehydrated or over-hydrated, the time may range from approximately one to three weeks.) In situations of voluntary refusal of food and hydration, death typically ensues on a similar time frame, although the early use of ice chips or sips of water to reduce thirst may delay this slightly.