Friday, July 26, 2013

Strong Mind, Strong Body: the link is Exercise

It is great to want to drop a few pounds to improve physical health and appearance.  But for many people that I have worked with, particularly those who have are at the beginning of what will be a long journey, looking better during that vacation to the beach is simply not in the picture yet.  Consequently, noticeable changes in physical appearance, while desired, are inadequate motivation.  For the person who starts, as I did, severely obese, that beach body is simply not going to cut it.  The mirror is a very unforgiving entity because nearly everyone is their own worst critic. Far too often, when exercise is discussed, it is only in the context of the physical benefits for the body.  Rarely, if ever, are the mental or emotional benefits considered.

This is tragic because it is through the underlying foundation of increasing mental and emotional strength that spurs on those who were once obese into the physical body.    Stress, anxiety, and depression are the most common and fastest growing mental health problems in America today.  One research group is predicting by 2020 that this will be the second-highest lifelong disease that will afflict both children and adults.  Only heart disease will surpass mental health as the most common of health problems in America.¹  Please understand that I am not some crazy person whom believes that the pharmaceutical industry is the only source of this problem or that all forms of prescription drugs are bad.  But, at best, it seems inappropriate and misinformed to rely solely upon drugs to fix problems of the mind.  After all, how smart is it to put complete trust in a drug treatment if the worsening of stress, anxiety, or depression is one of the possible side effects?  Call me crazy but I thought medicine is supposed to make you better.  Now, in no way I am saying that someone who struggles with these issues should ignore the advice of a doctor and completely forgo any use of what may be helpful medicine.  What I am saying is, that limiting treatment just to prescription medications is not exploring all of the options.  By taking this path, a person is missing out on what may be the best natural form of medicine available.

Stress and anxiety both cause a response by the sympathetic nervous system, commonly referred to as “fight or flight.”  This response is both physical and mental.  Physically, the heart rate increases as two hormones, epinephrine and norepinephrine are dumped into the blood stream.  Breathing rate and blood pressure also increase.  At the same time the brain focusing on the source of stress, sometimes to the exclusion of all other surroundings.  This process happens within a few short seconds with the aim of deciding and acting to either fight the stress or run from it.  Depending upon the nature of the stress this may last from a few seconds to a few hours, however, the body should return to its normal state shortly after the source of stress is absent.  Short-term stress is no big deal when comes to the body’s ability to cope.  However, long-term stress has several negative consequences that may lead to anxiety and depression.  The body is not meant to stay in this heightened state for days or weeks on end.

The body responds to stress primarily in two ways: the immune system and hormonal system, both respond differently when dealing with, chronic or individual, stressful situations.  The ability of the immune system to fight diseases and infections is suppressed.  The hormonal balance of the body can be thrown off, possibly disrupting sleep or other bodily functions, in severe cases long-term chronic stress may throw off a woman’s normal menstrual cycle.  People with blood pressure or other heart problems often see a worsening of the effects during stress.  Behavior and mood can undergo extreme changes creating substantial change in a person’s personality.

Exercise has been shown to help reduce, and given time and persistence, has the potential to eliminate the harmful effects of stress.  Under prolonged or extreme stress the immune system can be severely depressed.  This effectively makes it harder for the body to fight infections, viruses, and bacteria. A biochemical substance, αKLH, found in the brain plays an important role in activation of the immune system.  However, stress and anxiety will inhibit the brain’s ability to produce αKLH.  Exercise counteracts this by increasing the brains ability to produce αKLH.  In as little as six weeks of 20 minutes or more of daily physical activity the brain can increase the production of αKLH to reduce signs of anxiety and stress by almost half.²

Hormonally, serious changes take place as the result of stress and anxiety.  The pituitary gland is the region of the brain responsible for the vast majority of hormonal regulations of the body.  Under short term stress incidences large amounts of the hormone cortisol are released into the bloodstream.  Cortisol drastically raises levels of blood sugars and triglycerides.  These are released to provide the energy necessary to support a literal “fight or flight,” the body it preparing itself for a physical fight for survival or to run and hide.  In today’s modern society the overwhelming number of stressors do not require this kind of physical response, so this extra surge of energy goes unused, leaving blood sugar levels high.  In response, extra insulin, the hormone response for lowering high blood sugar levels, is released causing it to become stored as extra body fat.  This extra insulin is so effective during its response to stress that it often removed more blood sugar than necessary, resulting in low blood sugar, and causing the body to crave carbohydrates.  During this time most people reach for a candy bar or soda, causing the insulin cycle to repeat itself.  If the stressor is a chronic problem, cortisol levels will constantly be produced by the pituitary gland, potentially causing substantial weight gain.  Daily exercise reduces the output of cortisol during stressful times and, in combination with a healthy diet, minimizes the cortisol produced.

High levels of stress potentially may disrupt a sleep pattern.  A disruption in sleep prevents the pituitary gland from releasing the two most important hormones, insulin growth factor-4 (IGF4) and growth hormone, from restoring and repairing the body in preparation for the following day.  These two hormones are at the highest levels during the fifth and sixth hours of sleep.  A minimum of seven hours of sleep is needed to maximize the benefits of these hormones, more is better.  IGF4 and growth hormone focus on tissue repair and insulin regulation, minimizing body fat storage and improving muscle growth; the more intense an exercise session the higher response of these hormones.  Not only does poor sleep disrupt the good that these hormones do, but in response to poor sleep the pituitary gland secretes higher levels of insulin and ghrelin.  Ghrelin is the hunger stimulation hormone, have a poor night’s sleep and the body wakes up feeling hungrier.  This makes it incredibly easy to overeat the day after a night of little sleep.  Exercise reduces the presence of both hormones.

So how much exercise is necessary to improve the brain’s function and regulation of the body?  For people who are not interested in hitting the gym to lift weights or engage in intense cardio, light daily activity for 30 minutes is needed.  Easy activities like going for a walk, cleaning around the house, yard work will do wonders.  Lifting heavy weights, in the 4-10 rep range, four days per week for 45 to 60 minutes per session will accomplish this.  Fans of cardio need to engage in 5 to 6 sessions per week of 30-60 minutes at a moderate to intense pace.  Exercise performed with these guidelines improves and strengthens the brain’s response to stress and anxiety: a strong mind literally builds a strong body.  The stronger the body becomes the more effective the mind becomes at regulating the body and the body becomes even stronger.  A strong mind builds a strong body.  It is a cycle, ride it.


Sources Cited
1.       Exercise, Stress Resistance, and Central Serotonergic System. Journal of Exercise and Sport Science Reviews. Vol 39 (3), p140-149, July 2011.
2.       Physical Activity and Stress Resistance: Sympathetic Nervous System Adaptations Prevent Stress-Induced Immunosupression. Journal of Exercise and Sport Science Review. Vol 33, #3, p 120-126

                

Friday, July 19, 2013

Fantastic Fish Oil

Fish Oil is one of, if not the most popular, and well-researched supplements in the world.  There is more than twenty years of research into fish oil and fish oil supplements.  Until a recent research article, published in the July 2013 edition of the Journal of the National Cancer Institute surfaced, almost the entirety of fish oil research indicated positive benefits.  However, this recent article claims, and has made national headlines over the last couple of weeks, by claiming that fish oil may cause prostate cancer.  As someone who has prostate and daily takes fish oil supplements, I have a vested interest in fully understanding the ramifications of this research.  Before reviewing this specific research a little knowledge of fish oil needs to be understood.
Fish Oil, consumed through directly eating fish, or in a supplement form, is an Omega-3 fatty acid.  Omega-3 fatty acid is one of the healthy forms of fat that have many positive health benefits.  It is an essential nutrient, meaning that, the body does not naturally produce Omega-3 fats.  The only way to get this valuable nutrient is to consume it through food or supplementation.  The best sources of fish oil are fish (shocking, I know); the best fish to consume are mackerel, herring, tuna, salmon, anchovy, sardines, sturgeon, and trout.  Fish should be cooked by broiling or baking.  Fish sandwiches offer enough negative health benefits to offset the positives of eating fish.  Remember, if you fry nutrition dies.
Not a fish person? That is fine, supplementing is an excellent way to increase intake.  There is no particular brand that is better than another.  The key thing to be aware of is the source.  Look for fish oil supplements whose original source is one of the fish listed above.  Other fish contain Omega-3 fats but in lower qualities.  If the source is not one or more of these types of fish do not spend your money.  The two most valuable Omega-3 fatty acids are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA).  A quality product is going to dose 2000 mg (2 grams) of EPA and 1000 mg (1 gram) DHA.  Lower concentrations will not be cost effective because of the high numbers pills that will have to be consumed to have an effective dosage.  Higher concentrations are unnecessary unless recommended by a physician.  This is what the past twenty years of research has indicated as a healthy and productive way to utilize fish oil supplements.  So has one study changed that for men?
The news making headlines about the newly discovered link between fish oil supplements and prostate cancer created a bit of an uproar last week among proponents and opponents to fish oil. So what does the research say and is the buzz worth the fuss?  The original research appeared in an article entitled, Plasma Phospholipid Fatty Acids and Prostate Cancer Risk in the SELECT trial and is published in the July 2013 issue of the Journal of the National Cancer Institute.  So why the cause for concern?  It comes down to this one paragraph:
In this large, prospective trial, high plasma phospholipid concentrations of long-chain ω-3 PUFA were associated with statistically significant increases in prostate cancer risk.  These associations were similar for low-and high-grade disease and for EPA, DPA, and DHA, which are anti-inflammatory, metabolically interrelated ω-3 fatty acids derived from oily fish and fish oil supplements.
Even if the scientific language seems a little difficult to understand, the words “significant increase in prostate cancer risk,” and “oily fish and fish oil supplements,” jump out to everyone. Sound the alarms bells, don’t go in the water, another natural source of nutrients is horrible for you!  Welcome to over-reactionary and alarmist headline selling mainstream media field day.  Now that everyone is in a mass-panic, allow me to scrutinize and disseminate the actual research.
The Problems with this Research:
1.      The above quote is the only place in the entire 10 page research report that the words “oily fish and fish oil supplements” appear in connection to prostate cancer risk. HELLO RED FLAG!
2.      The research was not conducted for the purpose of understanding what, if any link there is between fish oil and prostate cancer.  The purpose of this study was to investigate a link between ω-3 fatty acids and prostate cancer.  However, and this is important, consumption of oily fish and/or fish oil supplements did not happen in this study.
3.      In fact, no form of food or supplementation of any kind, in this study.  Why? Because this study is not original experimental research.  This study did not give human participants given fish oil supplements and then test those participants for the development of prostate cancer.  This is a statistical review of previously published research.  Statistics can be manipulated.
4.      The statistical manipulation: through statistical, not experimental analysis, this study found than men without prostate cancer had average blood concentrations of EPA+DPA+DHA (the three most prevalent kinds of ω-3 fatty acids) 4.48%.  The cancerous population had concentrations of 4.66%. A difference of 0.12% is significant?
5.      The conclusion from this is that a man using fish oil supplements is 12/100s of a single percentage point more likely to develop prostate cancer?  Interesting conclusion, especially considering that this is statistical, not experimental, research and no actual fish oil supplementation actually took place.
6.      Finally, the researchers also claim ( I can’t believe this was not newsworthy), that naturally occurring ω-3 fatty acids increase the risk of prostate cancer while chem-lab created trans-fats, aka hydrogenated oils, actually lower the risk of prostate cancer.  This claim takes place in the second paragraph of the introduction to the research paper.  I laughed when I read that.  Not once, but twice in a statistical research review of other people’s research, the authors claim to have over-turned twenty years of research and tens, if not hundreds, of studies.  All without conducting an original experiment.
The Good that Fish Oil can do
            When it comes to this latest study, to say that I am a skeptic is an understatement.  So, I am switching gears and focusing on what we know fish oil can do.  Fish oil is best known for its ability to reduce inflammation within the body.  Inflammation is a broad term that can cover a variety of topics.  Generally speaking, fish oil aids the body in dealing with abnormal conditions or the presence of unhealthy substances. Fish oil has been mentioned in connection with several different health concerns.  In fact, www.webmd.com lists twenty-six different medical conditions that fish oil seems to improve.  Some are better researched and understood.  I present to you five of the best research-verified reasons to take fish oil. These conditions and dosages were taken from www.webmd.com.  Consult your physician for extra guidance.
1.      High Triglycerides- this is what started the original buzz with fish oil supplementation.  Fish oil supplementation can lower triglyceride levels 20-50% with daily supplementation for three-six months. Dose required: 1-4 grams (1000-4000 mg)/day.
2.      Heart Disease- may help prevent heart disease.  For people that already have heart disease it may help reduce the risk of dying. Dose 3 grams (3000 mg)/day.
3.      High Blood Pressure- ω-3 fatty acids expand blood vessels which has a direct effect on bringing blood pressure down. Dose 4 grams (4000 mg).
4.      Rheumatoid Arthritis- may decrease morning stiffness, I recommend taking it before going to sleep so that by the time you wake up it has been in your body for several hours. Daily dose: 3.8 grams (3800 mg) EPA and 2 grams (2000 mg)/day.
5.      Harding of the Arteries (Atherosclerosis) - helps to prevent plaque buildup in the arteries at 3 grams (3000 mg/day.  If plaque already exists 6 grams (6000 mg)/day may prevent further buildup and possibly remove existing plaque.

Based on this information, a daily dosage of 3 grams (3000 mg), broken down as 2 grams EPA and 1 gram DHA, have enough healthy benefits to make regular use safe for most people.  These are the best research-verified benefits of taking fish oil supplements. There are many other positive benefits associated with fish oil supplement, including cancer prevention, weight loss, and exercise-related inflammation. So knowing all of this, what is my personal take?  Let me just say, I have been taking 3 grams (3000 mg) of fish oil per day for almost two years now.  I am thirty years-old, I take it as prevention against these and many other health problems.  Prevention of a problem will always trump cure.  I won’t be stopping my use of fish oil supplements.

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.