Still, the mere thought of going without food for more than a few hours is terrifying to me — forget about 20 days. Skeptical, but curious, I did a bit of digging to find out what fasting was all about.
TYPES OF FASTING AND DETOXIFICATION
There are long-term and short-term fasts, medically supervised fasts, religious fasts, and even political fasts. But the four main types are juice fasts, modified juice/eating fasts, colonic cleansings, and supervised water fasting programs. With a juice fast, an individual drinks only fruit and vegetable juices for four to 30 days. In a modified fast, the individual would add herbal teas, some vegan foods and often laxatives. A colonic cleansing consists of various ways of flushing out and cleaning your colon, including taking certain herbal supplements. Finally, the water-only fasts are typically medically supervised and done in clinics for those with chronic diseases.
FASTING VS. “CLEANSINGS”
Fasting and “herbal cleansings” are vastly different, even though both are controversial and potentially dangerous. A “cleansing” typically involves the use of some sort of laxative. The idea is that toxins get stored in the colon and can have severe effects on the human body, leading to disease, aging and other illness. “The reality is that the colon is ‘self-cleaning’ and these products can cause serious side effects, such as damaging the very organs the ‘cleansing’ is trying to protect,” says Peter Pressman, M.D., assistant professor of clinical medicine at the University of Southern California. “The human body is a marvelous internally paced machine — our bodies are designed to get rid of wastes, bacteria, and other non-digestible food components through our stool.”
Those who fast experience a whole gamut of physiological and psychological effects. Some describe a heightened spiritual awareness and relaxation of the body — even a sense of letting go of pain from the past and developing a positive attitude toward the present. “The body can experience heart palpitations, an increased sense of awareness — almost a sense of euphoria. This is from the release of stress hormones used to process energy for your body while you fast,” says Timothy Patton, M.S., R.D., M.P.H., a professor of public health at Florida International University.
Typical discomforts seen in the early stages of fasting include: lightheadedness, irritability, heart racing, exacerbation of joint symptoms, muscle aches, headache, nausea, and mild abdominal discomfort. Additionally, many report that although the hunger subsides within the first few days, the fasting experience is still “difficult” — mainly due to bouts of boredom and psychological hunger. After the first few days, discomforts typically disappear and the patient feels well. Even during a prolonged fast, brain function remains intact.
WHAT HAPPENS TO YOUR BODY?
“Your body is a very efficient machine and is designed to handle a fast quite well,” says Patton. If you do a complete fast (that is, no food — only water to drink), your body first uses the tiny amount of glucose (blood sugar) you have running through your bloodstream for energy. When this is gone, the lack of food forces the liver to utilize a small amount of its glycogen (stored glucose).
The brain, vital organs, and other body functions still need to find another source of glucose to function when the liver’s available glycogen is used up. Luckily, our bodies have the amazing ability to convert proteins (from our muscles) into glucose so we can survive. Regrettably, we’re losing valuable muscle (especially if your body is not in a complete resting state).
What about using fat? Unfortunately, fat NEVER converts to glucose (fat is used to fuel muscles for extended physical activity), but instead is oxidized into an alternative, albeit inefficient, source of energy called ketones, which can be used to partially fuel the brain and central nervous system (glucose is the other needed source). This sophisticated survival system was designed to protect our bodies from starvation during the “feast” or “famine” days of early man.
“We detoxify for many reasons, mainly to do with health, vitality, and rejuvenation — to clear symptoms, treat disease, and prevent disease,” says Elson M. Haas, M.D. The health claims and benefits of fasting range from the complete detoxification of impurities (which proponents of fasting blame for most illnesses), curing colds, psoriasis, and arthritis, and even prevention of Alzheimer’s.
Clinical studies have shown that medically supervised water fasting can reduce symptoms of autoimmune illnesses and in many cases, bring about disease remission (specifically for rheumatoid arthritis, hypertension, and diabetes). “The idea of fasting under a controlled, medically supervised program can potentially be one of the biggest breakthroughs of the 21st century — especially for chronic diseases,” says Caldwell B. Esselstyn, Jr., M.D., former Chief of Thyroid and Parathyroid Surgery at the Cleveland Clinic. “Although the early research looks strong for certain diseases, there needs to be substantially more evidence before mainstream medicine embraces this type of treatment.”
Additional research demonstrated that rodents that fasted every other day seemed more resistant to diabetes than control mice or animals on calorie-restricted diets. Fasting also appeared to lower susceptibility to Alzheimer’s and cardiovascular disease. “Intermittent fasting seems to increase a rodent’s life span by stimulating and causing a mild stress on cells, which ultimately makes the cells more resistant to damage,” says Mark Mattson, Ph.D., a neuroscientist at the National Institute on Aging.
Despite these findings, even fasting experts believe fasting should not be a part of your everyday life. “I have seen amazing results with supervised water-only fasting, and careful refeeding (of a plant based diet), but juice fasting, detoxification — well it just doesn’t make much sense, and it can be unhealthy and even dangerous,” says Joel Fuhrman, M.D., of the Hunterdon Medical Center in New Jersey.
Advocates of medically supervised, water-only fasts see it as a method of “rebooting” your system. “Fasting is a way of introducing dietary and lifestyle change — starting fresh. But it’s not just about fasting; the reason that we have had great clinical success reversing chronic disease is due to the education, controlled supervision, and re-introduction of food and lifestyle,” says Alan Goldhammer, D.C. of True North Health in Rohnert Park, California.
The opponents of fasting (mostly physicians and healthcare professionals) are as ardent as fasting’s supporters. “No scientific evidence exists that fasting has any benefits for the body. In fact, a body that is starved or depleted would not be as effective or efficient at eliminating offending substances,” says Dr. Pressman. “In fact, it’s the height of arrogance to suggest that fasting and/or detoxification is going to boost the human body and do a better job of removing offending substances than the GI [gastrointestinal] tract, liver, and kidney.”
Fasting and “cleansing” programs can create a host of medical problems, including damage to your gastrointestinal tract and nutrient malabsorption, impaired liver function, anemia, kidney stones, and hypoglycemia. “Fasting (using laxatives) regularly and repetitive colonics lead to dependence on external laxatives, disturbing the body’s natural ability to do it itself,” explains Dr. Pressman. “Fasting also has the potential to be quite dangerous if it results in a delay in seeking conventional medical treatment.”
Gaining body fat is yet another possible hazard of fasting. “When you stop fasting, the first thing your body wants to do is nourish and refeed. If you eat the same unhealthy foods you had before the fast, you will gain body fat. Plus, you already lost lean muscle during the fast to supply energy. Now your body will demand high calorie and high fat foods, believing it’s going to starve once again. You’re back in the ‘feast’ stage,” says Patton. Therefore, fasting experts caution fasters to carefully choose nutritious foods for refeeding.
Other than for religious reasons, fasting can be a way of jumpstarting life changes. If you don’t eat for 15 or 20 days, any food will taste significantly better — so it’s easier to incorporate healthier options after a fast. As for disease-fighting capabilities, the jury’s still out. If you believe you need to fast on a regular basis to rid your body of impurities — well, most fasting experts disagree, advising a healthful diet in the first place. And, if you’re in it for “pop” spirituality, I’d say you’re better off with good, old-fashioned meditation — at least there’s less risk involved.