Fasting is primarily the act of willingly abstaining from some or all food, drink, or both, for a period of time. An absolute fast is normally defined as abstinence from all food and liquid for a defined period, usually a single day (24 hours), or several days. Other fasts may be only partially restrictive, limiting particular foods or substance. The fast may also be intermittent in nature. Fasting practices may preclude sexual intercourse and other activities as well as food.

In a physiological context, fasting may refer to (1) the metabolic status of a person who has not eaten overnight, and (2) to the metabolic state achieved after complete digestion and absorption of a meal. Several metabolic adjustments occur during fasting, and some diagnostic tests are used to determine a fasting state. For example, a person is assumed to be fasting after 8–12 hours. Metabolic changes toward the fasting state begin after absorption of a meal (typically 3–5 hours after a meal); "post-absorptive state" is synonymous with this usage, in contrast to the "post-prandial" state of ongoing digestion. A diagnostic fast refers to prolonged fasting (from 8–72 hours depending on age) conducted under observation for investigation of a problem, usually hypoglycemia. Finally, extended fasting has been recommended as therapy for various conditions by health professionals of most cultures, throughout history, from ancient to modern.

Read more about Fasting:  Health Effects, Medical Application, Political Application

Other articles related to "fasting":

Asceticism In Judaism - Fasting
... Nevertheless, fasting among the Jews was resorted to in times of great distress ... fast-day of the Bible received no less than twenty-two as companions (compare Fasting in Judaism) ... fast-days mentioned in the historical books of the Bible namely, that Oriental fasting is merely a preparation for the eating of the sacrificial meal ...
Fasting - Religious Application - Other
... fast of Geneva") is a public holiday and day of fasting in the canton of Geneva, Switzerland, occurring on the Thursday following the first Sunday of ... Rael teaches fasting for one 24-hour period per week, to give rest to the digestive system ...
Aztec Cuisine - Dietary Norms - Fasting
... salt and chilis and all members of Aztec society engaged in fasting to some extent ... Though fasting was common in Europe, there were permanent exceptions for the women and small children, the sick or frail and the elderly ...
Ta'anit (tractate) - Summary of The Mishnah and Babylonian Talmud
... various days with regard to strictness in fasting (§§ 4-6) nature of the national mourning in case no rain falls despite many fast-days (§ 7) ... Chapter 2 The ceremonies which must be observed in fasting (§ 1) the prayers and the blowing of the trumpet in this connection (§§ 2-5) the participation of the priests. 3 Cases in which the order of fasting may be changed, and the trumpet may be blown at the very beginning of the fast (§§ 1-3) other occasions on which a fast is held and the ...
Types of Abstinence - Food
... Further information Fasting, Vegetarianism, and Veganism Fasting is primarily the act of willingly abstaining from some or all food, drink, or both ... concerning that from which one fasts, and may be prolonged or intermittent as to the period of fasting ... Fasting practices may preclude sexual activity as well as food, in addition to refraining from eating certain types or groups of foods for example, one might refrain from eating meat ...

Famous quotes containing the word fasting:

    Did the first men who thought of fasting put themselves on this regimen on their physician’s order, because they had indigestion?
    Voltaire [François Marie Arouet] (1694–1778)

    The philosopher is like a man fasting in the midst of universal intoxication. He alone perceives the illusion of which all creatures are the willing playthings; he is less duped than his neighbor by his own nature. He judges more sanely, he sees things as they are. It is in this that his liberty consists—in the ability to see clearly and soberly, in the power of mental record.
    Henri-Frédéric Amiel (1821–1881)