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Jadienne Lord

Benefits of fasting?

April 3,2010



“The term, fasting, implies total or partial abstinence from food or water for any of a number of reasons.” For centuries people have believed in different types of fasts that can be beneficial in various ways. Therapeutic fasting can supposedly detoxify your body by cleaning it from the inside out, and give your organs a break. Religious fasting was used in order to become closer to God and increase spirituality. Other times fasting was thought to be a cure for various diseases, or at least could be used to relieve symptoms. Lately there has been controversy over whether “starving yourself” could truly contribute to overall healthy living. Through study it has been discovered that fasting can have positive and negative side effects, and can be healthy under certain circumstances.

Living in a toxic world?

The air is toxic with over 80,000 metric tons of carcinogens, released in the air annually in North America. The water is polluted with over 2100 chemicals in most municipal water supplies, and the food supply is contaminated with over 80% of foods having genetically modified ingredients ( With all these toxic chemicals around, fasting is seen as a way to “detoxify” or cleanse the body from the inside out. Even in religious fasting, abstaining from food is seen as a way to purify the body and the soul. Despite the long history of fasting, and the diversity of places it is found (nearly every religion has some type of fast); it often gets a bad reputation for encouraging starvation, or when people use fasting for weight-loss. There is also a dispute as to whether the body actually needs help detoxifying, or whether it does it on its own (

Information found on the Web

The origin of fasting for illness perhaps dates back the development of the present forms of animal life. Among undomesticated animals it is a common practice to fast when ill, though this is of course an instinctive procedure rather than a planned therapeutic measure. The first records of human fasting for the remedy of disease go back to the ancient civilizations of Greece and the Near East. The great historian Plutarch even said “instead of using medicine better fast a day.” As time progressed various doctors did studies studying the rejuvenating qualities of fasting on animals, some of the most important studying worms, who were nearly reborn by fasting. Rejuvenescence is a quality of fasting that humans share with worms, but to a lower effect. Fasting is also sometimes linked to longevity, but more research needs to be done to clear up all possible variables.

The websites I got this information from were both credible. Most of this information came from which is an article. Although the article itself is not by a well-known scholar, in the bibliography most of the information used came from the Sun-Diet Health foundation. This foundation was founded by Dr. William Howard Hay and Dr. Rasmus L. Alsaker, the former who claims to have cured himself of Bright’s disease through proper dieting, and the latter who is also a published doctor who focuses on nutrition. Several were also published by University presses, which make them more credible. The rest came from, which is a website that has its own independent medical review board and several doctors on staff. They are both presenting this information in order to inform people about fasting, although the second website has a more objective viewpoint.

In certain studies fasting has been shown to reduce risk of heart disease, increased memory in elderly, and reduce asthma symptoms. These studies were done by the University of Utah, National Academy of Sciences, and an unnamed organization respectively. This information is not quite as credible because it comes from a newspaper article, which only sites one study per topic ( Fasting is also a way to remove toxins from the body, because most are held in body fat which is removed during the fast.  This information is not quite credible because there are no studies cited, but the author is published (  Both the article and the website were designed in order to inform people of the benefits of fasting, so they are both somewhat biased.

Research Studies on the Benefits of Fasting In Specific Ailments

Hypertension and hypertension-related diseases are some of the leading causes of poor health and death in industrial developed countries. In two separate studies fasting was researched as a possible way to alleviate hypertension (Goldhamer et al, 2001) and borderline hypertension(Goldhamer et al, 2002), in humans. Both used water-only fasting techniques. In the study with hypertension 174 people with blood pressure in excess of 140/90 mm Hg were treated with a 2-3 day pre-fasting period, followed by a 10-11 day water-only fasting period, followed by a 6-7 day re-feeding period. The borderline hypertension study had 68 participants with blood pressure in excess of 119, but diastolic less than 91. They also had a 1-2 day pre-fasting period, but was followed by a slightly longer (avg. 13.6 day) water-only fasting period, followed by a 6 day re-feeding period. In the hypertension study the average blood pressure loss was 37/13 mm Hg and in the borderline hypertension study the mean loss was 20/7 mm Hg. These results suggest that fasting is an effective treatment for both borderline and full blown hypertension.  These results also point to medically supervised fasting as a way to promote healthy living in addition to reducing blood pressure.

Research Studies Reporting Negative Side Effects of Fasting

One study on the effects of fasting and/or a protein free diet on the levels of urea on a rat’s liver used 3 groups of 16 rats to contrast urine content. One group was allowed 15% casein, another 0% with dextrin substituted in for casein, and another water-only. A control group of 8 rats was also included. The results showed that there was a decrease in liver weight present and an increase in urea excretion. This is one form of protein depletion that could potentially be dangerous (Schimke, 1962). Another study used rats in order to show that ribosome content steadily decreases during a fast. The fasted rats in the experiment were given water-only (Hirsch et al, 1966).

Religious Fasting

Fasting has been used spiritually since before the time of modernized organized religion. In many cultures adolescents were required to fast in order to pass the initiation into adulthood. In the bible there are also various instances of fasting, as Moses received the 10 commandments he fasted for 40 days and 40 nights. In Judaism and Islam there are specific periods of fasting (Tenth of Tebet and Ramadan respectively), (Rogers).  Fasting is also used to direct individual lives into a deeper intimacy and to reconnect with God. Religious fasting often only lasts throughout the daytime, one meal after sundown may be eaten. But usually the length of the fast and how serious the person is determines how much food intake is allowed. (Ryan).

Summary and Recommendations

There are a variety of fasts taken for a variety of reasons. Fasting is safest done with medical supervision, but if one is careful, fasting can also be done safely without a doctor looking on. The main focus would be the reason for the fasting. For weight loss fasting is not the best or even a good option. According to webmd not only is it unsafe to fast for extended periods of time, but when the person begins to eat again his/her metabolism will be slower than before, which means it will be easier for that person to regain and put on additional weight. People will also be more likely to binge eat after denying themselves food for an extended period. Fasting for up to 10 days can be beneficial for those who have hypertension disorders, or are close to developing one since it has been proven to lower blood pressure. As far as “detoxification” more studies will have to be done to prove that the human body does not do an adequate job of removing toxins by itself. Religious fasting should also be done carefully; a prolonged fast could lead to the body becoming malnourished which could lead to permanent problems. If fasting is necessary, try a juice fast or a “Daniel’s fast” which is just fruits and vegetables and would not be as harmful. Water-only fasting, especially without consulting a doctor, should be kept to a minimum, as it’s the most dangerous. While fasting the person should try not be too active because they’re not receiving any calories for energy. With all that in mind, make sure to heavily weigh whether fasting is absolutely necessary for the effect you want.

Research Studies used


Goldhamer AC, Lisle DJ, Sultana P, Anderson SV, Parpia B, Hughes B, Campbell TC. (2002).

Medically supervised water-only fasting in the treatment of borderline hypertension. J Altern Complement Med. 8(5):643-50

Goldhamer A, Lisle D, Parpia B, Anderson SV, Campbell TC. (2001). Medically supervised water-only fasting in the treatment of hypertension. J Manipulative Physiol Ther. 24(5):335-9.

Negative Side Effects

Schimke, Robert. (1962). Differential Effects of Fasting and Protein Free Diets on Levels of Urea Cycle Enzymes in Rat Liver. Journal of Biological Chemistry. 237:6.

Hirsch, Carl and Hiatt, Howard. (1966). Turnover of Liver Ribosomes in Fasted Rats. Journal of Biological Chemistry. 242: 5936-5940.

Books Used (Religious Fasting)

Ryan,T. (1981). Fasting Rediscovered: A Guide to Health and Wholeness for Your Body-Spirit. Ramsey, NJ: Paulist Press.

Rogers, E. (1976). Fasting: The Phenomenon of Self-Denial. Nashville, TN: Thomas Nelson, Inc.




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