Intermittent Fasting 101
The biggest question I have gotten since starting this site (The “IF” Life) in 2008, is how to effectively use “Intermittent Fasting” (also known simply as “IF”, hence the name of the site) to achieve their goals and maximum results.
It is also the main reason I started this website, to help spread all the information below.
Results and goals can vary by each person with fat loss, muscle gain, better health, improved performance in your sport of choice and more. With all that also factors in the individuality of what is a person’s insulin resistance, current body composition (body-fat%), daily lifestyle, eating habits, macronutrient ratios (carbs/protein/fat), type of exercise program, frequency and volume of training, recovery demands, and so forth.
What I am trying to hint at is that you are unlikely to find large groups of people with the exact same set of parameters and responses to an intermittent fasting protocol.
What does this mean? Well just that you need to start with a basic intermittent fasting (or “feeding” as mentioned below) format, and then learn how to monitor results and adjust as you go.
Even down the road things will change as you improve health, lower insulin resistance and maybe change performance and recovery needs. So nothing is really ever just one set way (as it shouldn’t have to be).
Life is dynamic (always changing and evolving) and so should be the way you see your own journey for health and fitness.
What is Intermittent Fasting (IF)?
For those that may not be familiar to the term, intermittent fasting is just taking “intermittent” times of fasting (no food) and working them into your lifestyle. This can be either daily or a couple times a week (will get into that more below).
From what I have read/learned from years of independent research on reduced calorie intake (CR) and IF (**studies listed at end), the conclusions are that using short-term calorie restriction/fasting may be effective when it comes to:
- Reducing blood glucose and insulin levels (improving the state of the overall glucose metabolism)
- Increasing fatty acid oxidation with increased FFAs (through increasing lipolysis hormones GH, glucagon and adrenaline)
- Sparing and preserving muscle tissue (lean mass)
- Increasing various health factors (lower inflammation, lower blood pressure, reduced oxidative stress, increased protection against neuro-degenerative diseases, and more)
- Keeping the metabolism strong/healthy (as eating more meals does not “speed up” your metabolism)
There are also a multitude of lifestyle benefits such as not being a slave to eating all day long (like modern “diets” seem to preach), having more natural daily energy/focus, and even just learning how to enjoy eating once again (with good foods and friends).
Overall it can be a simple eating lifestyle that can not only help you lose weight, but more importantly let you relax and provide relief from obsessing about food or “diets” all day.
How To Start Using IF
Is there only one set way in which to use intermittent fasting?
No, of course not.
I could easily come up with several different IF protocols based on people’s individualistic needs, lifestyle, exercise, goal, macronutrient ratios, and so forth. However I am going to keep it simple and give the 2 most frequent intermittent fasting (IF) options seen.
- Longer IF 1-2x a week: This is taking a longer fasting period of say for up to 24 hours and repeating 1-2x a week. Note that 24 hours is not skipping a whole day, as stopping to eat on 6pm Tues and then having your next meal at 6pm Wed is 24 hours. I usually don’t talk about anything longer than 24-32 hours for using IF, as most research is usually based on that fasting window (even if some studies have more frequency with alternate day fasting).
- Shorter “Daily” IF: This means that it is done more than a couple times a week (can be daily) with a condensed eating window and less fasting than seen above. I also like to call this “Intermittent Feeding” instead of fasting. For example someone could be eating their calories in a 6-8 hour window daily (and the fasting part happens around it).
With those approaches there are still many variables to include such as calories, activity/exercise, recovery needs, food choices, etc.
In the end it is still about finding a way that does work for you. Picking the approach you think fits around your lifestyle best is going to lead to better results.
Here are some of the pros and cons of each approach for you to consider.
Longer (24 hr) Intermittent Fasting 1-2x a week:
Some of the pros for a longer fast are:
- Allows a person to make sure they are getting enough calories on the non-fasting days (as it is not supposed to be a quick “crash diet” or severely calorie restricted overall).
- Keeps meals simple on days that you use IF (usually just one small meal later in a day).
- Allows you to eat “as normal” on other days (perhaps a better starting point for those that don’t want to change much of the rest of their diet/foods up).
- Longer fasts may provide a deeper cellular cleaning (autophagy). Worth noting that this may also be achieved with exercise.
Some of the cons for a longer fast are:
- Chance of overeating (binge) after a longer fast, making weight loss benefits not happen (calorie excess overall).
- Less of a focus on daily healthier food choices (as I like to say that even a “skinny” person can get heart disease and cancer)
- Longer fasts are a bigger stress on the body, and may not be suitable for people who have already a high stress load or metabolic/blood sugar/health* concerns
- May not work well with high active lifestyle if calories are still too restricted overall.
More “Daily” Intermittent Fasting (or “Feeding”):
Some of the pros for a shorter daily fast/feeding window are:
- Keeps an eating schedule simple and more consistent (day after day).
- Helps to break free from the mental concept of “needing” to eat all the time.
- Allows your body to adapt it’s hunger (hormones, circadian rhythms) for more consistent feeding times.
- Focuses on the importance of nutrients and healthier food choices each day.
- Reduces the importance of “snacking” (which is a hidden mental factor leading to many weight issues nowadays).
- Intermittent shorter fasting windows may be a less stressful starting approach for those with metabolic/blood sugar/health* concerns.
- Helps to focus also on daily lifestyle and stress balance overall to make it successful (which is all part of the equation).
Some of the cons for a shorter daily fast/feeding window are:
- Can possibly cause weight loss plateau if calories are still too low for too long (again not meant to be a “crash diet” or severely calorie restricted).
- May not be suitable for people with high calorie demands (activity) and still not eating enough overall.
Wrapping it Up
Over the years I have personally gravitated to the more of the “daily” IF approach without really planning. I like the more consistent daily strategy and freedom. Just seemed natural and to fit me best.
I eat anywhere from 6-8 hours a day (feeding window) around 2 main meals of lunch and dinner, and then not worry about food outside of that. I’ve adapted over the years and eat more instinctual without being in any rush most days.
I focus more on healthy foods and the results come, while still being able to enjoy other splurges when I go out and eat/socialize.
I’m not a slave to some mentality of “needing” to eat all day and enjoy the freedom that comes with that. No longer can I be “sold” on some better eating plan, as I have found mine.
On occasion (not more than 1x a week and not every week) I may even work in a 24 hour fast for a “deeper” cleanse, but there is more flexibility to how I approach eating now.
I listen to my body and know what is right for me. I am my own expert (which is what I want for you as well). Staying at a leaner body-weight year round is much easier once you can do that.
The key part of the IF experience is just starting with it and seeing how it works for you. Knowing how to change things up when they aren’t working. Making a lifestyle solution and not needing anyone to tell you how to eat again. That is how you find that freedom and results that last.
Is this some kind of fad detox quick weight loss diet?
Funny enough, I’m sure that’s what I would have thought about all this 10+ years ago drinking all my shakes and eating every 2 hours. However nowadays, I am a believer of a different kind.
I’m not a fan of quick weight loss or detox diets, as sometimes I believe the only real “cleansing” you get is in your wallet.
Now that’s not to say you can’t have many benefits from using IF, I just think alot of this comes down to more about calories (low calories always lead to quick weight loss but not usually sustainable) and better food choices.
Your body seems to detox at it’s own pace without needing any special shakes or diet plans.
I like to say that IF is just a “tool” to use in your lifestyle. It brings some benefits but still just one factor in the bigger equation. Making IF work for you is really the best way to approach it.
What can I eat or drink while fasting?
Well the simple answer is nothing (outside of water) for a “pure” fast.
I (and many others) also enjoy drinking coffee or tea in the AM, so I’m not really going to tell you that you can’t have it. As for all the other “no calories zero” diet drinks or “no sugar” gum, you will be better off just skipping them.
I do personally make an exception to add in some fat to my morning coffee, namely coconut oil. To me while it may not be a “pure” fast, I also do believe it enhances my daily intermittent “feeding” schedule (and doesn’t seem to take away from the fast itself).
How many calories should I be eating?
Think of weight loss as achieving some calorie deficit in the bigger long term picture than day to day. So there is no special amount to worry about each and every day, but should keep it in check.
Focus on eating mostly real foods and that is a good start.
If you achieve a small deficit on most condensed eating days and still eat out once a week higher in calories, weight loss can happen. If you eat at maintenance daily and do a longer fast couple times a week (and eat below maintenance on those days), weight loss can happen.
I would suggest against going too low in calories though as you may just head down a road of severe and chronic calorie restriction (and the problems that go with that).
Plan your simple lifestyle of eating how you enjoy first, then start to worry about the calories (or you may find out you don’t have to).
Is this based on low-carb, Paleo, or any other diet plan?
Fasting is fasting, how you eat (“feeding” part) the rest of the time is up to you. If you can make it work, go for it.
People tend to get the best results sticking to real foods (meats, eggs, butter, vegetables, fruit, etc) but it’s nothing that can’t be changed or remain flexible.
Remember, it is still about making IF work for you as a “tool” in your lifestyle….and there may be more than one way that can happen.
What about needing protein every few hours?
It is worth noting that the supplement industry is a multi-billion dollar industry (yeah…B…as in Billion!). There is much to be gained from convincing people not only to eat often, but also making it protein. I know the feeling…been there long ago.
However when you look at all the research and mechanisms of muscle repair in the big picture (24+ hours), it appears the answer may be as simple as just getting in enough per day.
How much protein is needed is another question, but it’s probably not as much as you think.
What’s the best kind of exercise to do with IF?
I also like to say that the IF in “the IF Life” stands for Intensity Fitness. What that means is using short “burst” of more effort (resistance/bodyweight training, higher intensity intervals) to generate better post workout responses for fat loss, muscle repair and also nutrient usage (amino acids, glycogen).
Keep in mind many of these metabolic responses can be for 24-48 hours!
Trying to use IF along with excess or chronic exercise (mostly in the “cardio” range) will probably not work as well. This increases demands for recovery (another kind of stress) and can lead to eventual “burnout” if not managed properly.
A short and intense workout circuit or intervals can do wonders 2-3x a week, and then your attention should be on how you eat (80% of your results are there after all). After that, just go be active however you enjoy in life…or in short “go play”!
*Important Disclaimer: Intermittent fasting is intended only for healthy adults. I am NOT a doctor/nutritionist/dietitian nor has anything said here been approved by the FDA for treatment of any disease (see site terms for full disclaimer). Everything above is for informational purposes only. Use any information at your own risk.
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