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Fasting – Effective Therapy For Health Concerns

Dear Dr. Klaper:

I have sore joints and high blood pressure. I have heard that water fasting can be a great treatment for many serious diseases, including the ones I have, but missing lunch is agony for me. The thought of not eating for days – even weeks – seems terrifying and totally impossible. How does fasting work and how could someone like me do a long fast to help overcome health problems like mine? – Robert K.

Updated: January 27, 2017

Dear Robert K.,


If there were a pill that effectively treated high blood pressure, overcame Type II diabetes, consistently produced dramatic improvements in autoimmune diseases such as lupus, rheumatoid arthritis and psoriasis, and provided effective relief for asthma attacks and migraine headaches it would be seen as a wonder drug of the highest order. Yet, such profound improvements in these medical conditions, and many others, are routinely seen during a water fast lasting more than a few days.

I am on the clinical staff of TrueNorth Health Center in Santa Rosa, California (about one hour north of San Francisco), a nutritionally-based clinic specializing in reversing chronic diseases. The most powerful tool we have to improve our health is a whole foods, plant-based diet.

After all, virtually all the debilitating chronic diseases that afflict people in Western societies are the result of their high-fat, overly-processed, salt-sugar-and-oil-laden, animal-based food stream that people pour through their tissues hour after hour, day after day, year after year, courtesy of the Standard American Diet (SAD). 

When a truly health-promoting food stream based on whole, plant-based foods is run through the body, day after day, month after month, year after year, most disease processes stop in their tracks and true, deep healing begins.

Although a water fast can be a very powerful way to initiate healing, and to bring rapid and dramatic improvement to common and life-threatening diseases, real healing power is found in a whole foods, plant-based diet, not in a water fast, per se.

Most people’s experience tells them that going a day or two without solid food produces profound hunger and discomfort. The thought of going two or three weeks or longer without food leaves them incredulous, and certainly not eager to undertake such a trial. After supervising hundreds of fasts, many lasting 2-3 weeks, and some up to 30 or 40 days, I can report the happy news that reality is nothing like (much better than) the feared image people hold about fasting. 

How can this be?

For the first 24 to 48 hours after beginning a water fast, the body burns off circulating blood sugar and sugar stored in the muscles and liver in the form of glycogen. The “real” metabolic fast does not begin until one metabolizes their blood sugar, in approximately 2 to 3 days. At that time, the body begins to burn fat tissue for fuel. When that happens, molecules called ketones enter the blood circulation. These ketones have some very interesting properties.

For the faster, the main welcome property of ketones is that they suppress hunger. By day four or five of a water fast, hunger is usually gone and is replaced by a feeling of great well-being. 

Why more energy, and not less? 

So much of the energy that the body uses all day goes to digesting our food including muscular contractions of the intestine, chemical energy used to synthesize stomach acid, bile, and digestive enzymes as well as the billions of immune cells in the intestinal lining that interrogate the chemical nature of the food going by in the digestive tract. When that function is no longer required on a fast, all that energy is freed up and people surprisingly – but predictably – feel very light and energetic for the first several weeks on the fast.

It may be counterintuitive, but it is true nonetheless. The commonly-held image of a long water fast is of a person lying on their bed, weak, hungry and whimpering, trying not to think about food, when actually, the reality is quite the opposite.

People at our TrueNorth Health Center who are on a water fast, frequently stop me in our courtyard to say “Doctor, I haven’t felt this good in years! I haven’t eaten for three weeks, but I feel wonderful!” It really is quite remarkable. 

It is during this time that we observe a normalizing of blood pressure and blood sugar readings and a subsiding of most pains, swellings, and other signs of inflammation. (See corresponding references below.)

During a fast, the body is in “Full Energy Conservation Mode” and it does not want to spend precious chemical energy on chaotic, heat-generating, activities, such as inflammatory reactions and growing tumor tissue. During a fast, hot angry joints in rheumatoid arthritis, gout and other inflammatory joint diseases (predictably) cool down, inflamed plaques of psoriasis in the skin are becalmed, and wounds in and on the body heal extremely well. If malignant breast cells are multiplying in tissues, the fasting body generates molecules called sirtuins which put the breaks on cancer growth.

Thanks to molecules called ketones, by day four or five of a water fast, hunger is usually gone and is replaced by a feeling of great well being.

People emerge from a water fast feeling lighter and cleaner on the inside because they really are!

Water fasting cleanses the body on a deep, cellular level

All of us, in our body cells, have remnant molecules of every restaurant meal, fast food snack, and processed food dessert we have ever eaten. There are flavorings, colorings, preservatives, dough conditioners, stabilizers, and thousands of other compounds that compose a chemical soup of modern cuisine in all the cells in our body. These substances accumulate in our tissues over time, contributing to feelings of chronic fatigue and bodily dysfunction. 

A water fast has the effect of “taking your cells through the car wash” where day after day, nothing but pure water washes through each and every cell. This markedly lowers the concentrations of the foreign, disruptive molecules. 

Thus, it is no wonder that people predictably emerge from a water fast feeling lighter and cleaner on the inside because they really are.

Any water fast lasting longer than three days should be done in a facility where medically-trained staff can supervise the process. Such supervision is necessary so that pulse, blood pressure, and other clinical parameters can be checked daily and laboratory tests can be performed on a regular basis. There is an art to supervising a fast, and experienced health professionals are essential to make sure that all goes well and that the fast is ended before any significant problems arise.

The action of all medications, herbal supplements, vitamins, etc. are all potentiated on a water fast. For that reason, all medications except thyroid replacements, must be stopped prior to the fast. Dosage of thyroid medication is cut by half during the fast. 

For people who are on medications that they cannot stop, such as prednisone, antidepressants, etc., a water fast is contraindicated. These people should NOT water fast, but rather, do a juice cleanse.

juice cleanse, done with freshly squeezed vegetable based juices, is a wonderful, healing program. One does not experience the ketosis that occurs during a water fast, but a few days or weeks on healthful juices, can be a very potent force for healing, especially if one is used to consuming a meat-based, highly processed diet. But, again, the key to lasting health is not the fasting, but the quality of the diet after the fast.

The water fast is broken in a gentle matter, starting with vegetable juices or fruit chunks like watermelon, and progressing through phases of gradually increasing fiber content, namely raw vegetables, steamed vegetables, and eventually denser foods such as rice and beans.

One of the greatest benefits of a fast is that it “re-tunes” the tongue’s taste buds through a process called neuroadaption. Whole, natural foods begin to taste really delicious again. This opens the way for one to retool their dietary choices and let a truly health-promoting food stream of whole, plant-based foods pour through the body every day, thus creating lasting and glowing health.

See my 55-minute DVD or On Demand Video, “Fasting: Safe & Effective Use of an Ancient Healing Therapy.” If you suffer from any of the following or have other chronic health problems, this illustrated presentation is for you: High Blood Pressure, Rheumatoid Arthritis, Cystitis, Type 2 Diabetes, Migraine Headaches, Crohn’s Disease, Colitis, Angina Pectoris.

To your good health and happiness,

Dr. Michael Klaper


1) Medically supervised water-only fasting in the treatment of hypertension. Goldhamer, A et al. J Altern Complement Med 8 2002 643-650.

2) Improved metabolic control after supplemented fasting in overweight type 2 diabetic patients. Vessby b, et al. Acta Medica Scandinavica 1984; 216;67-274.

3) Changes in laboratory variables in rheumatoid arthritis patients during a trial of fasting and one-year vegetarian diet. Kjeldsen Kragh, J et al. Scan J Rheum 24 1995, 85-93.

4) Antirheumatic effects of fasting. Palmblad J. et al. Rheum Dis Clin North Am 17, 1991, 351-362.

Okamoto, O, Fasting diet therapy for chronic urticarial: report of a case. J Dermatol 19, 1992 428-431.

5) Influence of fasting on the immunological reactions and course of acute glomerulonephritis. Brod J., et al. Lancet. 1, 1958, 760-763.

6) Diet therapy for the patient with rheumatoid arthritis? Oxford Journals, Medicine & Health, Rheumatology Volume 38, Issue 11, Pp. 1039-1044. Lancet. 1991 Oct 12;338(8772):899-902

7) Controlled trial of fasting and one-year vegetarian diet in rheumatoid arthritis. Kjeldsen-Kragh J1, Haugen M, Borchgrevink CF,

8) Metabolic regulation of Sirtuins upon fasting and the implication for cancer. Curr Opin Oncol. 2013 Nov;25(6):630-6. Zhu Y1, Yan Y, Gius DR, Vassilopoulos A.

9) The multifaceted functions of sirtuins in cancer. Angeliki Chalkiadaki & Leonard Guarente. Nature Reviews Cancer 15, 608–624 (2015)

NOTE: A version of this article about fasting by Michael Klaper, M.D. appears as “The Benefits Of Water Fasting” in the Winter 2017 issue of Naked Food Magazine.

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