EST Alternative Health BLOG

So now we move on to what happens during a fast. I have already discussed the various reasons for fasting and what may be accomplished in various time frames in my previous post ‘To Fast or Not? For How Long?’ Here I will focus on the physiological changes that take place during a fast.

In preparation for the fast one should change to a reduced calorie diet composed primarily of cleansing fruit, vegetables and water for a couple of days. This prevents adverse reactions, which might occur due to a sudden change in diet when you actually start the fast. Once you start the fast, the body goes into the initial ‘not fed’ state that normally occurs between meals. This means that during the day the body is using ‘aerobic respiration’ to break down glycogen stores into glucose. At night, the ‘at rest’ state of aerobic catabolism (breaking down) of fats (lipolysis) will take place as normal. As long as one is not exercising, these normal states of energy production will usually last 24 to 48 hours for females and 48 to 72 hours for males. [3]

If one is on a ‘water only’ fast, The body will have used up most of the stored glycogen and readily available fatty acids by this time. Its first reaction is to begin scavenging non-essential protein as it is more readily available than stored fat (triglycerides). The protein is turned into glucose, which goes primarily to the brain. However the body does not like losing protein mass and if no other energy source is available it will soon switch to stored triglycerides using a process called ‘Ketosis’. In this highly efficient state, the liver begins converting stored fat and other nonessential tissues into ketones, which can be used by the brain, muscles, and heart as energy. It is at this point in the fast that sensations of hunger generally go away, and many people experience normal or even increased energy levels. Hormone levels and certain functions become more stable in this state as well. The goal of most fasts is to allow the body to reach the ‘ketosis state’ in order to burn excess fat and unneeded or damaged tissue. Thus, fasts longer than three days are generally recommended as therapy.

Weight loss occurs most rapidly during the first few days of a fast, up to 2 pounds per day. In following days, the figure drops to around 0.5 pound per day. An average weight loss of a pound a day for an entire fast can be expected. [3] One reason for this is that the body recognizes that there is little or no nutritional input and it turns down your basal metabolic rate, so that you require less calorie input to maintain your existing weight.

One side effect of burning fat, is that any drugs, prescription or otherwise, nicotine, and environmental toxins previously stored in the triglycerides will be released into your blood stream. Your liver, kidneys and lymphatic systems will be taxed to eliminate them. Support them by drinking lots of water and herbal teas. You may feel some lightheadedness or even headaches. These are not unusual ‘healing crisis’ symptoms. If the symptoms become severe, you may be experiencing a ‘Herxheimer’s reaction’, which means toxins are being released faster than the body can eliminate them. So, slow down the process.

If instead of a ‘water only’ fast, you choose to use juice or broth, you will be slowing down the burning of stored fat and the release of toxins as the body will have a small input of carbohydrates, which will interrupt the state of ketosis and reduce weight loss. In fact you may never enter the ‘ketosis state’ if you use juice, shakes or broth fasts, but weight loss is still posible.  Experienced fasters recommend slowly diluting the juice or broth with water until you are drinking mostly pure water by the end of the fast. My experience is that I have lost up to 20 lbs. on 28 and 30 day juice and broth fasts. This may not be the maximum possible, but it is certainly significant.

Fasting is not starvation, but rather the body’s burning of stored energy. Starvation occurs when the body no longer has any stored energy and begins using essential tissues such as organs for an energy source. Therapeutic fasts are stopped long before this happens. It is estimated that even very thin people can survive for 40 days or more without food. [3]

I hope this material has been helpful. Please register and leave comments.

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Don Gillmore, Licensed Massage Therapist(15 yrs), B.S.- Life Sciences

Bibliography:
       1.  Fundamentals of Anatomy & Physiology, Third Ed., Frederic H. Martini, Prentice Hall, Englewood Cliffs, NJ, 1995.
       2. Prescription for Nutritional Healing, James F. Balch, MD & Phyllis A. Balch, CNC, Avery Publishing Group, Garden City Park, NY, 1993.
       3. Gale Encyclopedia of Medicine – Fasting, 2nd ed.. Douglas Dupler, MA, Gale Group, 2002.

When a meal is digested, the calories released are used to replace liver and muscle energy stores as glycogen and operate the nervous system. Oxidizing(burning) one gram of fat releases approximately 9.5 kilocalories (Calories). Oxidizing one gram of carbohydrate releases 4.2 Calories and protein 4.3 Calories. Excess calories are stored as fat. A very rough average Calorie consumption for an adult is 70 C per hour or 1680 C per day. [1] This number will vary greatly based on age, gender, physical activity, physical condition, body weight and muscle mass. However, the following rule applies to everyone. Eating more Calories than your body uses in a day results in fat storage and weight gain. Eating less Calories than your body consumes results in weight loss. In the strictest terms of calorie count, where the calories come from is irrelevant, however the speed with which calories are released during digestion can have profound effects on your sense of fullness, energy level and sense of well being. Generally sugars convert to glucose almost immediately releasing all of their calories at once. Monoglyceride fats may be immediately available for use as an energy source in the nervous system, but in general, fats and proteins are slower to metabolize, releasing their calories over time.  Of course, the issue of consuming ‘empty calories’ vs. whole foods, which included micro-nutrients, vitamins & minerals is central to natural healing.

There are four basic mechanisms for producing energy. How the body uses these mechanisms to produce energy changes over time. It also depends on energy input and demand. For the first three hours after a meal our body is using glucose, glycerol and amino acids derived from carbohydrates, fats and proteins in our meal. It is also converting glucose into glycogen for storage in the liver and muscle. This process is called ‘glycogenesis‘. As stated above, excess calories are stored as fat at this time. After the initial three hours, the body enters a ‘not fed’ state, where the mitochondria inside a cell begin to break down stored glycogen into glucose in the presence of oxygen. This is called ‘ aerobic respiration’.

Intracellular glucose is almost immediately available for physical exertion, but ATP production from glucose depends on oxygen availability in the cell, which can be used up in approximately 17 seconds during physical exertion. [1] Once available oxygen is depleted, the cells must switch to an anaerobic (no oxygen required) energy production mode outside the mitochondria. This also involves breaking down stored glycogen and is called ‘glycolysis’.

At night, we enter an ‘at rest’ state during which muscle energy demand is low and skeletal muscle cells begin to break down fatty acids in a process called ‘lipolysis’. The amount of Calories burned by our muscle tissue during the night is primarily a function of our muscle mass and our basal metabolic rate (BMR), which is controlled by the thyroid. The more muscle mass you have the more calories you burn in the ‘at rest’ state. However, at rest, we may burn as few as 50 Calories per hour and it takes a 3500 C exertion to burn off a pound of fat. That’s 70 hours of ‘at rest’ fat burning. [1] It is possible to increase one’s BMR with supplements such as cayenne pepper, green tea, ephedra, ma huang or caffeine, which are often included in weight loss formulas. It is this mechanism that many supplement manufacturers allude to when they claim their product will turn you into a ‘fat burning machine’. The additional fat loss may be real, but it is minimal, while the hype is excessive!

Physical exercise temporarily raises the BMR during the day. Consistent physical exercise several times a week will maintain a higher BMR as long as one continues to stay active. If one becomes sedentary, the BMR will drop over time. Various levels and types of physical exercise will burn different amounts of calories in a given time period. Walking at 2 mph for 30 minutes, a 150 lb. adult will burn 90 Calories. Jogging (a 10 minute mile) for the same time they would burn 345 Calories. 30 minutes in a far infrared sauna at 130+ degrees Fahrenheit is claimed to burn 600+ Calories. But, these are not necessarily fat calories. Fat must be catabolized in the presence of oxygen. As we have seen above, skeletal muscles switch to anaerobic gylcolysis after just a few seconds of exertion. Therefore, fat loss is minimal during strenuous physical exertion. However, you are likely to increase oxygen capacity, tone muscle, increase muscle mass and lose inches. That’s good. It just doesn’t result in large weight loss.

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Don Gillmore, Licensed Massage Therapist(15 yrs), B.S.- Life Sciences

This turned out to be a long post. Therefore, I have broken it into three parts. Part one will discuss the relationship of carbohydrates, lipids (fats) and protein. Part two will discuss energy production and usage under normal and exercise conditions. Part three will discuss energy usage during short and long term fasting programs. A bibliograpy is included in ‘Part Three’. This may be more information than most are interested in. However, if you understand how your body stores, creates & uses energy from the food you eat, you will be less likely to be taken in by all of the over hyped weight loss and cleanse programs out there. No doubt about it, there is a lot of hype about cleanses & weight loss programs. Some of it is true, some of it is partially true and some of it is so patently misleading that it should be criminal! Some of the beliefs about nutrition have been repeated for so long or repeated by so many that they are taken at face value in spite of no scientific evidence or even in spite of scientific evidence to the contrary.

Let me make it clear that I am not a scientist, nor an expert. I have studied human physiology at the undergraduate level fairly extensively. I have worked in the alternative health field for 15 years. I read a lot and I try to apply some logic to understanding the natural healing process.

Here in lies a paradox. The living human body as a whole is not easily studied by standard laboratory techniques. Chemical reactions must be isolated and random variables eliminated in an attempt to apply the scientific method. Organic chemists and physiologists have learned and continue to learn a lot of valuable information using these techniques. Unfortunately, science and scientific medicine have a hard time arriving a ‘facts’, ‘proofs’ & ‘cures’ when confronted with too many variables, some of which they have no way of sensing, quantifying or reproducing in a consistent way.

However, each individual human body is a complex entity influenced by DNA, health history, diet, lifestyle and beliefs both spiritual and secular. And yes, I do believe that our strongly held beliefs can change physical reality in profound ways. The human body has a tremendous ability to heal itself, especially if we can support it through healthy diet, lifestyle and positive thoughts. This is natural healing. This dichotomy between what science can prove and what experience tells us sometimes happens, leaves patients and practitioners of natural healing free to believe that almost anything is possible. Knowing that many of us want to believe, some have capitalized on this to feed us what we want to hear so that we will buy their products. So, now that I have that lengthy preamble out of the way, I would like to present a brief scientific explanation of the physiology of energy storage and retrieval in the human body as it applies to daily activities, physical exercise, fasting and/or weight loss.

Our food is generally classified as carbohydrate, fat or protein. Actually, most of our food is, in it’s natural state, before it is processed, is a combination of all three, plus enzymes, micro nutrients, vitamins and minerals. To discuss the topic of energy pathways in any coherent way we must talk about how the body processes these things individually.

Carbohydrates may be simple sugars such as glucose, sucrose & fructose or more complex sugars and starches such as many root vegetables and plant fiber or the animal starch glycogen. Glycogen is how energy is stored in our liver and muscle tissue. [1]

Lipids (fat) may be fatty acids (saturated or unsaturated), glycerides (mono, di, & triglyceride), prostaglandins, steroids, phospholipids and glycolipids. It is triglycerides that absorb and store lipid soluble vitamins, drugs or toxins in our bodies. Fatty acids are also stored in the liver for use in bile salt, steroid, and energy production. [1]

Proteins are made from smaller compounds called amino acids, which are linked together by peptide bonds. Proteins are classified as dipeptide, tripeptide or polypeptide. [1]

All three of these are made up of carbon (C), Nitrogen (N), oxygen (O) and Hydrogen (H) molecules, which form compounds that can be broken down and in many cases rebuilt by the body as needed. Breaking down carbohydrates, fats and proteins releases more energy than is required to break the molecular bonds. This energy can then be used by the body to build other compounds it needs. Adding a phosphate group to a substrate such as adenosine diphosphate (ADP) creates adenosine triphosphate (ATP), which is the energy exchange molecule used by chemical processes throughout the body.

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Don Gillmore, Licensed Massage Therapist(15 yrs), B.S.- Life Sciences

Want to stir up a really heated debate between doctors and natural healers? Bring up the subject of fasting.  In general, the medical community considers fasting a ’starvation diet’, which is unsafe and very bad for you.  They are right in that anorexic – bulimic behavior really is hard on your system, but fasting is not starvation. On the other hand, natural healing practitioners believe that the body can heal itself without pharmaceutical or surgical intervention. Fasting is one tool in that healing process. However, even within the natural healing community there is a wide range of opinions on what is the ‘correct’ fasting diet.

I have done fasts as short as one day, but usually five days and as long as 28 days. I have never done a ‘water only’ fast.  Water only fasts can pull toxins from your system faster than they can be cleared out resulting in a severe ‘healing crisis’ or Herxheimer’s reactions.  I have done fasts for their own sake and as part of a detoxification ‘cleanse’.  Dr. James Balch, MD & wife Phyllis Balch, C.N.C. in their book “Prescription for Nutritional Healing”, recommend: 1.  a three day fast to help the body rid itself of toxins and cleanse the blood; 2. a five day fast to begin the process of healing and rebuilding the immune system and; 3. a ten day fast to prevent problems before they arise and fight off illnesses, including degenerative diseases that have become so common in our chemically polluted environment.

Fasting one day a week on watered down juice or a vegetable broth gives your digestive tract a ‘day off’ in which it can relax and restore itself.  Fasting for three days may help the body cleanse itself, if you eat a cleansing diet of fresh fruit or juice (not canned or artificially sweetened) and vegetable broth, but the body does not start consuming stored fat and digesting unwanted foreign protein until day four or five.  In terms of overcoming the sense of deprivation, days one through three have always been the hardest for me.  After that, a sense of ‘being in the flow’ of the fast sets in and most cravings fall away.  However, I do maintain a constant intake of water, green and herbal teas, juice (watered down by 1/2) and vegetable broth.  I also maintain a vitamin supplementation and a small amount of bulk fiber (usually psyllium, but sometimes a banana).  Here, I disagree with Balch & Balch.  I believe (especially on ten day and longer fasts) that chemical toxins and body wastes are being dumped into the colon and need to be swept clear of the body before being reabsorbed.  The psyllium also helps reduce the ‘empty’ feeling one may experience during a prolonged fast. 

No one recommends that you fast for more than three days without the supervision of a qualified health care practitioner. Lactating and pregnant women should never fast.  If you are experiencing acute symptoms of pain, weakness, fever or have diabetes, hypoglycemia or other chronic health conditions, consult your doctor before engaging in even a short fast.  Otherwise, sensible fasting can be a short cut to feeling better quickly.

For a more in depth discussion of the physiology of fasting go to this three part post.

       1. Prescription for Nutritional Healing, James F. Balch, MD & Phyllis A. Balch, CNC, Avery Publishing Group, Garden City Park, NY, 1993.
       2. Gale Encyclopedia of Medicine – Fasting, 2nd ed.. Douglas Dupler, MA, Gale Group, 2002.

Don Gillmore, Licensed Massage Therapist(15 yrs), B.S.- Life Sciences