Juice fasting, also known as juice cleansing, is a controversial fasting method and a detox diet in which a person consumes only fruit and vegetable juices to obtain nutrition while otherwise abstaining from food consumption. Juice fasts may last anywhere from a few days to several weeks. The juice consumed during a juice fast is not the type commercially available, but rather that produced from freshly juiced fruits and vegetables.
- Reasons for fasting 1
- Methods 2
- Studies 3
- Possible side effects 4
- As a detox diet 5.1
- See also 6
- References 7
Reasons for fasting
Reasons to undergo juice fasting may include spiritual or religious reasons, detox, desire to lose weight, or attempts to stop habitual behavior such as smoking, drinking soda, overeating, caffeine addiction, etc. Participants may use juice fasting as an alternative medicine. Participants may believe juice fasting will cure chronic pain, cancer, depression, arthritis, severe infections that resisted antibiotics, autoimmune diseases, and many other diseases. One reason for juice fasting is to assist with other methods of gallstone passage. Others choose juice fasting because they believe they can focus on healing specific organs and systems.
Some practitioners fast bi-annually in week-long (or longer) periods to attempt to purify the body in synchronization with what they believe to be annual cycles of nature. Fasts may even involve retreats and travel, such as with popular week-long spa-resort style trips to Thailand.
Because pure juice contains little to no fiber, juice fasters may use enemas or herbal or saltwater laxatives during the time of fasting to efficiently expel waste from the intestines and colon. Another method to achieve this effect involves mixing psyllium husks in with the juice. Because psyllium is not absorbed by the body, but greatly increases in volume upon water absorption, it creates the bulk necessary to facilitate evacuation.
Typically proponents of Juice fasting encourage juice to be consumed within 72 hours of being made and for juices to contain 80% vegetables to 20% fruits, to avoid excess sugar and maintain a high nutrient value.
In a reduced-calorie study, participants juice-fasted for one week without limitation of physical activity. The study demonstrated a temporary reduction in total free cholesterol. However it was also noted that within a week of ending the fast cholesterol had returned to prefast levels.
Possible side effects
Fasters should take care to maintain their intake of vitamins and nutrients during fasting, though no specific side effects are associated exclusively with juice fasting. Juice mixes containing grapefruit juice may also adversely interact with certain prescription drugs.
Because of the low sodium content of most fruits and vegetables, salt deficiency may occur. Salt deficiency causes headaches and weakness, then light-headedness, then nausea.
As a detox diet
Scientists, dietitians, and doctors regard detox diets as less effective than water-fasting, and hence a waste of money. Catherine Collins, Chief Dietician of 
Detox diets, depending on the type and duration, are viewed as potentially dangerous and can cause various health problems including muscle loss and an unhealthy re-gaining of fat after the detox ends.
- "Fasting". Retrieved 2012-02-25.
- Foster, Cynthia (2003). "Medical Doctor Explains How To Do A Juice Fast". Dr. Foster's Essentials. Retrieved 2006-03-22.
- Kotkas, L. J. (1985), "Spontaneous passage of gallstones", Journal of the Royal Society of Medicine (Royal Society of Medicine Press),
- "Healing Weightloss Detoxification". Fasting.ws. Retrieved 2012-02-25.
- "Juice and Feast Website". Retrieved 2015-03-13.
- Huber; Nauck; Lüdtke; Scharnagl (February 10, 2003). "Effects of one week juice fasting on lipid metabolism: a cohort study in healthy subjects.". S. Karger GmbH, Freiburg. Retrieved February 20, 2013.
- "Grapefruit Juice and Some Oral Drugs: a Bitter Combination". Nutrition Bytes (UCLA). 1999. Retrieved 2009-05-04.
- Mark Kurlansky, Salt: A World History, (Penguin Books, 2002) p.9.
- Debunking detox
- The Truth About Detox Diets