Friday, July 12, 2013

Intermittent Fasting: The Art of Skipping a Meal with Benefits

Just in case it is not clear; the only way a person becomes overweight is by eating too much.  So perhaps the suggestion of skipping the occasional meal should not be a shocking one.  While skipping a meal may have some health benefits it is not as simple as just missing the occasional meal.  After all, it goes against one of the most promoted health guidelines of the last ten years: don’t skip meals because it will make it harder to sustain energy levels to meet the physical activity needs.  Intermittent fasting (IF) is not a random choice to skip a meal or stop eating for a specific period of time.  It is a purposeful action build around a plan that accommodates nutritional needs as well as lifestyle. 
For a really in-depth look at IF, I highly recommend reading Experiments with Intermittent Fasting by Dr. John Berardi.  A free copy of it can be downloaded from www.precisionnutrition.com.  This is where I started my research before beginning my own experiments with IF.   Dr. Berardi discusses six different methods of IF. After reading his book, I found there were two methods that would be manageable for my lifestyle.  Since I am speaking from personal experience, I will limit my discussion to the two methods I used.  But before diving into that, a basic understanding of the scientific reasons for employing IF needs to be understood if the practice is to be implemented in a positive way.
So way back in the pre-historical days of humankind, before civilization and farming practices became commonplace, we humans were a bunch of nomadic hunters that  only were able to eat after encountering an animal that was slow enough for us to run it down and bludgeon it to death.  Three squares meals per day via refrigerators and drive-thru were not an option.  For this reason, it is theorized that the human body is capable of going prolonged periods of time without food or suffering from the detrimental side effects from not eating.  From this is built the idea that in modern times, a prolonged period of not eating could still render positive health benefits.
So what does the science say about this?  In reality, not a lot, the reason for this is simple.  Almost all of the research regarding nutrition for the past fifty odd years has been about what foods to eat and when; very little research exists about the effects of deliberately not eating.  However, this is changing, unfortunately it will probably be another five to ten years before any definitive research is completed and published.  So what we have now is a small group of fitness professionals and enthusiasts, of whom I now consider myself, conducting personal “experiments.”  Admittedly, this is a potential weakness of IF, not that it does not work because my personal experience tells me it does, but that the scientific community has not caught on to the concept enough to invest time and money into formal research.  Do not be alarmed by this, much of the research-verified “science” begins this way.
The premise of IF is that it enhances the body’s ability to undergo a normal process called autophagy.  Simply defined, autophagy is the body’s mechanism for breaking down and removing damaged cells so that new cells may be built to take the place of the damaged ones.  The entire process is far more complicated than that.  But, that is the process in a nutshell.  This is established scientific fact.  Now, let’s turn the page into the theoretical side.  This is where more formal research needs to be done.
The general theory that proponents of Intermittent Fasting promote goes something like this: in general, people eat far too much food, in particular, processed foods full of additives and chemicals.  By doing this, the body exerts all of its efforts into removing the chemicals and other garbage that it should not be taking in.  Because of this concentrated effort, it can never fully engage the process of autophagy.  When the process of autophagy is reduced or completely prevented, the body is unable to remove the damaged cells and metabolic by-products that are naturally produced by the body.  When the body is unable to remove this metabolic waste it hangs around, ultimately increasing the internal aging of the body. 
Sound confusing?  The bottom line is this: the body’s natural ability to remove its own biochemical waste is impaired.  Allowing this excess waste to stick around will gradually ruin the body’s ability to complete its normal, natural processes.  The deteriorating ability of the body to care for itself has a commonly known name: aging.  If research bears out this theory as true then it needs to be understood that by preventing autophagy people are quite literally making themselves older at faster rate than birthdays ever will.
How does fasting help?  It is pretty simple; by taking a break from eating the body receives an opportunity to play catch up.  It can completely remove the processed garbage from the body and fully engage the process of autophagy.  If the body has an opportunity to completely remove its own metabolic waste and replaced damaged cells with healthy, undamaged ones, it will function better.  Theoretically defined periods of fasting may actually help the body stay younger longer.  This happens because autophagy allows the body to resume its normal processes from everything to replacing bad cells to repairing injuries.  It may also enhance the body’s ability to rid itself of excess body fat.
Intermittent Fasting is the process of developing a structured and defined period of going without food for the specific purpose on enhancing this process.  As I mentioned earlier, there are several methods that can be used to accomplish this.  But I do not advocate anything that I have not personally experienced and with which I agree.  So I will only discuss the two methods that I have tried thus far: a 24 hour fast once per week and a daily fast of 16 hours following by 8 hours of eating.  Before going into the specifics of how each of these methods work, I want to spend some time addressing the common experiences between the two, both good and not so good.
The Good
1.       Learning the difference between physical and psychological hunger.  I am willing to bet that very few people, if anyone, who lives in North America, experiences true physical hunger.  Psychological hunger is when your brain tells you are hungry.  This typically occurs 4-5 hours after your last meal.  The brain says it’s hungry so you eat.  But will you die from a lack of food if you do not eat? No.  However, go a full 24 hours or more without food and your body will begin to experience true physical hunger.  The kind of hunger, that if nor satisfied, could lead to more serious health problems.  Learning to recognize the difference between psychological and physical hunger can make it easier to avoid giving into an unhealthy meal and be willing to wait until healthier options are available.
2.       Increase mental focus and energy.  I immediately noticed that after about six hours without food my ability to focus on the task at hand improved.  I also felt a greater sense of satisfaction of accomplishment once a task was complete.  The increased sense of energy was more of a mental alertness and not a physical one.  There was a sense of increased critical thinking and intellectual reasoning.
3.       Easily managed change.  One of the keys to successfully eating healthy is to make healthy choices in food selection.  But for many people that task is a daunting challenge.  Mentally, I found it far easier to simply forget about eating for a little while, than it is to be concerned about planning healthy meals.  In no way to I consider fasting to be an endorsement of eating unhealthy junk the rest of the time but it can be a pleasant break from the mental and emotional challenge of being food conscience at every meal.
The Bad
1.       Going without food.  Fasting is uncomfortable until the body becomes accustomed to it.  Whatever method of fasting is employed, expect that it will take three or four experiences to adjust to it.  Stick with it and the positive benefits will outweigh the complications but know that there will be a brief uncomfortable adjustment period.
2.       Decrease in social skills.  This too is temporary and will pass.  But the first several hours, until the brain shuts off the hunger signal, may make a person a little grouchy.  Coffee drinkers should consider an extra cup in the morning to help offset the less than sunny disposition.  Be aware of this and make an extra effort to get along with others.  They will be doing the same with you.
As I already mentioned, there are two methods of Intermittent Fasting that I have personally experienced and would recommend trying: a 24 hour fast once per week and a daily fast of 16/8.  So where should a person begin?  I would start with the 24 hour fast.
The 24 hour fast is the simplest to implement: simply stop eating for 24 hours.  However, in order to ensure this works a few things need to be considered.   Will an active social life interfere with completing the fast?  I would also not recommend training in a fasted state, at least not in the beginning.  Intense exercise in a fasted state may present serious problems.  However, low intensity exercise like walking can be safely done.  The time day of for beginning and ending of the fast must also be considered.
Taking these concerns into account, I chose to fast from dinner time Saturday evening until dinner time Sunday evening.  Typically this would mean eating my last meal at 6pm Saturday and breaking the fast at 6pm Sunday.  This worked will for me for a few reasons:  Sunday is always a rest day from exercise; it is also a day of little social activity outside of time with my family, eliminating the temptation to ruin the fast by eating out; by starting the fast after dinner Saturday the first 12-14 hours of the fast were spent relaxing before sleeping for several hours, helping to avoid the first psychological hunger pangs.
I attempted the 24 hour fast every Sunday between January and the end of March.  So what happened?  By the first Sunday in February, my body had adjusted so that I could go 24 hours without feeling the slightest bit hungry.  Another side benefit, I lost about a pound per month with attempting to lose weight.  I started in January weighing 184lbs and the end of March I weighed 181lbs.  Could this once a week 24 fast be away to help lose extra pounds?  Maybe, but keep in mind that one pound per month in weight loss is not impressive, but, it did happen without any specific attempt to lose weight.  The other six days of the week I ate to maintain my body weight.  Also, I regularly exercised five or six days a week during this time period.  I would not consider this a reliable way to lose significant amount of weight, particularly for people that do not exercise.  Regardless, it is still an excellent method for receiving the other aforementioned benefits.  It is the simplest way to begin personal trials with IF.
The other method that I attempted is called the 16/8 fast.  Everyone fasts but with most people simply utilizes a 12/12 fast; they eat over the course of the day, starting with breakfast and ending with dinner, most people eat over the course of twelve hours then taking a 12 hour fasting break between dinner, overnight while sleeping, and ending the fast with breakfast.  Skip breakfast?  I know it sounds crazy since the last couple of decades breakfast has been promoted as the most important meal of the day.  The 16/8 method simply extends the overnight fast from 12 to 16 hours by skipping breakfast and waiting until lunch to eat.  But it is not that simple.
This method is probably going to be less effective at enhancing the process of autophagy, for physically inactive people, than for people regularly exercise 4-6 days per week.  It is thought that for physically inactive people it takes 20-30 hours without food to enjoy the maximized benefits of autophagy.  However, exercise seems to enhance the process and shorter that time frame down to 12-16 hours.  In other words, physically active people can receive the cleansing benefits of autophagy in about half the time that it takes for inactive people.  The other major caveat to the 16/8 method is in order maximize  the autophagy in a shorter time frame; exercise must performed for 45-60 minutes prior to breaking the fast with the first meal.
This method presents two obstacles: exercising in a state of low blood sugar and consuming an adequate caloric intake in a time frame that is one-third shorter than what most people do.  Exercising in a fasted state of low blood sugar is relatively safe and doable for anyone that is not diabetic.  However, it does take some getting used to.  During the first week of using this method I deliberating backed off the intensity of my workouts while adjusting to the exercising in a fasted state.  During this week my workouts consisted mainly of light body weight exercises and stretching.  I completely stopped all of my heavy weight lifting and intense sprint workouts.  During the second week I reintroduced the weight lifting and sprint but do so with an intensity that was only about 75% of what I had done prior to this experiment.  It was not until the third week of eating with the 16/8 method that I resumed my workouts at full intensity.  When making any change to diet that could have an effect on the availability of energy and intensity of exercise, always make the changes gradually over a period of several days or a few weeks, and make one change at a time.  Changing too many things or changing too quickly will cause more frustration and setbacks than success.  This change to exercising intensely in a fasted state worked because I gave my body time to adjust.  That left the harder of the two challenges to conquer.
Getting nutrition right is always the hardest part of any program aimed at improving health and fitness.  With the 16/8 method the challenge lies in eating the correct number of calories in a shorter window of time.  It is important to note, that I did not decrease my caloric intake when starting this IF method.  I continued to eat the same number of calories I always eat when maintaining body weight.  For me that is 2100-2400 calories per day depending upon the type of workout on the given day. So what happened?  I followed this method from May 6th until June 13th, a total of five weeks, before taking a break while on vacation.  Without attempting to, I dropped from 181 (I maintained this weight thorough April until May 6th) to 177 lbs. Four pounds lost in five weeks when I was not trying to lose weight.
Why is that?  Well there are two reasons for that, the first is that by waiting to eat the first meal of the day after 16 hours instead of after 12, with the autophagy process enhanced the body has a better opportunity to break down stored body fat and use it for energy.  However, my opinion is that this is a minimal effect.  More likely, is that by waiting to eat after exercise the body maximizes the immediate use of calories, making it far less likely that there will be excessive calories to be stored as body fat.  As a result, the elevated metabolic rate results in more body fat being utilized for energy as the body recovers from exercise.  More research needs to be done to identify to what extent each of these reactions contribute to increased fat loss.  My personal experience taught me that this would seem to be an easier way to lose weight than the traditional three to six meals a day.
This leaves two questions to be addressed: who should utilize IF? Also, are there any restrictions or special considerations that need to be considered?  As I mentioned earlier, I think anyone considering using IF as a fitness tool should begin with the 24 hour fast, particularly if a person has no experience with deliberate fasting.  It is far easier and less stressful to stop eating for 24 hours than it is to perform it on a daily basis.  Having said that, the only population that should use caution with fasting would be blood sugar-related problems such as hypoglycemia or diabetes; consult your doctor if you have these or other blood-sugar related problems before trying IF.

The 16/8 method is a more challenging situation.  Based upon the research that exists and my own experience, this method should be used only by those who have a few years of experience with exercise and dieting.  I would also wait until having at least three months experience of doing a 24 hour fast once a week before beginning the 16/8 method on a daily basis.  Within these guidelines, IF has the potential to beneficial to everyone, however, be sure to pay attention to how IF affects energy levels both during times of fasting and eating.  While taking a planned break from eating may be beneficial; this is one area of health and dieting where too much will not be a good thing. Remember, make changes slowly, and use caution.  

No comments:

Post a Comment