Is Intermittent Fasting Right For You?

Is Intermittent Fasting Right For You?

You've heard all about IF. Maybe it's the potential health benefits that are catching your eye and enticing your curiosity. Or maybe it's the fat loss claims. Does it work? Or is it just another fad diet?


We’ll take a look at 4 main goals for people are generally interested in when looking into a new diet and see how they relate to IF.

  1. Health Benefits

  2. Fat Loss

  3. Muscle

  4. Athletic Performance


We’ll also discuss important information to help you determine if this is for you!

Is IF suitable for women?

So you’ve decided to try it, here’s how to prep for IF.

What is IF?



Intermittent Fasting is an eating pattern that involves fasting at different intervals. Some of the most common methods of intermittent fasting  include:

  • 16:8 in which you fast for 16hrs and you leave yourself with an 8hr window to consume your daily food intake.

  • The Eat-Stop-Eat (or 24hr fast once a week) where you do not eat for a full 24hrs then back to regular eating habits for the rest

  • The 5:2 Diet where you consume an extremely low amount of calories 2 days a week (500-600cals/day) then regular eating habits the rest of the week.



These are the most popular not only in terms of adherence but also in terms of evidence. There are other forms of IF but these are the most evidence based methods and that's what we're all about!



Why would fasting be a good idea and who would want to do it?



Fasting has been around for thousands of years. It is a part of many religions and even seen a form of cleansing (body and soul).



There are also heavy fat loss claims with people preaching that IF helped them lose fat, get lean and improve vitality.



If you're looking to lose fat or improve insulin sensitivity along with other health benefits, IF just might be for you!



Let's briefly examine the research and see if there's any evidence of these claims.



Potential Health Benefits

  1. Potential Health Benefits




There ARE a few very important health benefits that have been associated with intermittent fasting.




  • Improved insulin sensitivity is one of the most proven and effective benefits.




Why is improving insulin sensitivity important and how does it work?




If you have poor insulin sensitivity (some call this insulin resistance) you're predisposed to many inflammation based diseases such as diabetes. Without getting too deep into this subject here are the basics you need to understand:




People who are insulin resistant have a higher risk of diabetes, heart disease and heart failure, obesity (particularly abdominal obesity), osteoporosis, and certain types of cancer. In fact, diabetes is directly dependent on insulin sensitivity. If you're body has become completely insulin resistant, your pancreas stops producing the insulin required and you will NEED insulin shots to stay alive.




Changing your diet to lower the amount of a blood sugar during a meal is one of the best ways you can combat insulin resistance.




Intermittent fasting helps in this aspect! By decreasing your meal frequency, you're not spiking blood sugar as many times per day. Intermittent fasting is also known to decrease the amount of food you can consume because your window of opportunity to eat is small. You may be full after two regular sized meals and thus not allowing such a high blood sugar spike. This means that your body needs to produce less insulin to manage the glucose uptake. In turn this allows it to slowly start producing Beta-cells again which are crucial in synthesizing insulin.




One last important thing to note is that insulin sensitivity is not only important to diabetics and pre-diabetics! Improving your insulin sensitivity can actually help anybody get leaner and healthier. The better insulin sensitivity you have means the better your body can utilize insulin to shuttle glucose into your muscle as fuel as opposed to fat cells as well, fat.




Resistance training is another culprit of increasing insulin sensitivity. When you resistance train your muscle cells become sensitive and literally hungry for glucose. This means your next meal is more likely to shuttle glucose to receptors in muscle cells as opposed to staying in the bloodstream and causing inflammation and metabolic disturbances.




Intermittent fasting has also been associated with the following:

  • Higher levels of human growth hormone

  • Improved cellular repair

  • Better environment for gene expression

  • Increased lifespan (in rat studies)

  • Brain health (higher levels on a hormone that promotes nerve cell growth).




Although they are all extremely important in their own respects, I grouped those 5 titans together for one reason:




They are all related to the fact that intermittent fasting can clear up a lot of metabolic disturbances caused by excessive inflammation. Significantly overeating, or even eating a poor ratio of low nutrient density foods with high density calories can promote high levels of inflammation which can ef you up! IF promotes times where there is less dietary interferences during digestion which allows your body to carry on it's regular functions properly.




Why Does That Matter?




It matters because the health and fitness industry can be full crap. There are endless examples of people and companies marketing to you and playing off your emotions. These companies try to sell you on an idea that their method is the only way to do things. Health and fitness just so happen to be hugely linked to emotion for obvious reasons. This is why research is so important.




Intermittent Fasting can be an amazing diet that will likely work for you but it's not the ONLY way to succeed. It's not the only way to lose fat and it's not the only diet that promotes health. The Keto diet , low carb diets and even plain old flexible dieting (where you count your macros) are all associated with health benefits.




Most of these are effective due to decreasing inflammation and decreasing rates of obesity. More research is coming out showing that many health benefits of certain diets are actually just based on the fact that your body is going in the opposite direction of obesity. Don't forget that obesity is one the leading cause of premature death and diseases in North America and Europe.




Now before you jump on the IF bandwagon you MUST know a few opposing arguments/facts.




Intermittent fasting is exactly what it says it is - “intermittent”. That means that fasting for longer may actually be detrimental to your health. This is because your body needs nutrients and needs a certain amount of calories to function properly. Fasts that are longer than the recommended time frames backed by science may actually make you less healthy. Some specific examples include vitamin deficiencies that can lead to disease. As well as some bacterial or viral infections that require a healthy amount proteins to fight them off. If you suffer from a certain disease you may actually be robbing your body of what it needs so make sure IF truly is IF.




Fat Loss

2. Fat Loss





Intermittent fasting can absolutely help you lose fat! It can be a great fat loss tool depending on what habits you prefer to adhere to.





Just like ANY other diet, IF can offer unique health benefits but DOES NOT work any better for fat loss than ANY OTHER diet.





This is because in order to lose fat, you simply need to intake less energy (in calories) than you expend. No matter what diet you choose to follow.

IF can help you do that by restricting the window of time that you can eat food. If your problem is that tend to eat huge portions of food, IF is great because it eliminates 1-2 full meals you'd have in a day so you don't stuff your face for 3-5 meals /day. Instead, you're restricted to stuffing your face in an 6-8hr window (or skipping a full 24hrs 1 day a week).





Let's say you eat 4 meals a day at 1000cals per meal. That's 4000cal. Say you try intermittent fasting and now your limited to only 2 meals but you're really hungry so you eat 2 meals at 1500cals each. That's 3000 total Cals, 1000 less than what you normally eat. That's how you can lose fat on this diet.





Let's use low carb diets as a comparison.

Going keto or low carb can help you lose fat as well. The benefit of low carb is if you tend to mostly over consume carbs, this forces you to eat less carbs meaning that if you still eat the same as before but restrict carbs you're essentially eliminating extra calories.





Let's say you regularly eat 500 grams of carbs in a day (that's 2000cals) but you want to lose fat. Going on a low carb diet might restrict your 100g/day (that's 400cals). This means you're eating 1600cals less per day assuming that you still eat the same amount of protein and fat in a day.





Point is that it's the same formula no matter which fat loss diet you prefer as long as calorie intake is less than you expend. Simple as that.





Intermittent fasting can absolutely work as a fat loss tool if you do it right and if it fits your lifestyle!





Building Muscle

3. Building Muscle






This is where IF isn't so good. Technically you CAN build muscle while intermittent fasting but it's not an optical way to build skin splitting muscles. In most cases you can only build muscle in a calorie surplus. This means you must eat more calories than you expend to feed the muscles and provide adequate protein to support new muscle growth. Building muscle is one of the last things in your bodies list of priorities so it needs to make sure it's vital organs are taken care of before it can start using your protein as a muscle builder.






If you're doing IF let me tell you, it's REAL difficult to eat enough to build muscle in just a few hours.






Most importantly, protein synthesis is an ever lasting marry-go-round with something called a “protein turnover rate”. This means that every few hours your body gets rid of used and broken proteins and now has room for more new proteins to support muscle growth. In dietary terms this is called “Protein pulsing”. Generally giving your body a solid dosage of protein every 3-5hours will keep protein synthesis high. If you do IF, you're clearly restricted as to when you can eat and therefore will not be able to optimize muscle growth.






Having said that, myself along with other colleagues have tried IF during maintenance periods and haven’t noticed a significant decrease in muscle growth. So from our anecdotes , IF will not likely decrease your muscle mass either.






Athletic Performance

4. Athletic Performance

This is a tricky one. There are strong advocates for and against this subject. On one hand some people suggest strongly against IF for athletes due to the Decreased protein synthesis and worry about not feeding them enough energy. Many athletes themselves say they felt like crap and had decreased performance on the field when trying IF.







On the other hand, some athletes prefer it! They felt more aware and more in control.







My speculation is that it's not only a case of individuality, but also a case of the demands of your sport. We won't go deep into this because it's a whole topic of it's own.







Is Intermittent Fasting Effective For Women?

Is Intermittent Fasting Effective For Women?








This is crucial to understand before trying IF.








Research has shown that IF is much less effective for women than men.








This could be due to hormonal regulation.








There are tons of anecdotal evidence from women who miss their periods while fasting and having it return to normal after stopping IF.








The research does back this up however, they were studies dinner with animals.








If you miss your period you should STOP IF. Also, it may not be a good choice if you're pregnant or breastfeeding.








IF Prep

IF: The Initial Prep








So you decided to give it a shot! Okay, great. There are a few things you should know to prepare yourself before diving into it. Preparation is one of the keys to successful habit change so don't skip this!








Mental Prep:

This is totally new to you. The last time you did any sort of fasting was that day you woke up late, had to take the kids to school before work so no time for breakfast then had a meeting which went through lunch so all you had was a coffee.








That's different than regular IF. A planned fasting means you need to prepare yourself for some unusual activity. For one, you're probably going to be hungry, like really really hungry the first few times you try it. The good news is that you eventually learn to curve that hunger. Your body also gets used to it and less of your hunger hormones are produced (ghrelin). There are also some great little tricks to help you curb that hunger the first few times. Coffee and Tea! Everybody loves coffee. The caffeine in coffee and some teas is actually an appetite suppressant. Having a couple a day can prevent your almost unbearable hunger during your initial IF bout. Also the flavour of coffee and tea provides some satiety.








Like most changes, it takes a few weeks for your body to adjust so be patient.








Workout Considerations








I can thank Dr. John Berardi of Precision Nutrition for this one. He took a shortcut and produced his own research complete with workout log, weigh ins, and even blood work to see if health markers improved. JB had some help from Krista Scott-Dixon and He tried many forms of IF. They had this to say about training during IF:








  1. If some is good, more is not better.

    Whether cure or poison, the magic is in the dose. Remember that fasting is a physiological stress. Keep it short, manageable, and intermittent.

    2. Consider your overall stress load.
    If you’re dealing with a sick child, a demanding job, poor sleep, travel, etc., do not add extensive fasting to this list. Stress includes training.

    3. Do not train too much or too hard on a regular fasting program, especially if you are also cutting calories.








JB hated the 2 day/week fast. He found it to be “Not productive. Not mentally healthy. Not for me.”








JB loved the daily 16:8 fast. “This plan went really well. We have another winner… almost.” He then noted that the break in period was long and painful. He would use greens supplement, BCAAs and teas and coffees to ease into the fast.








At the end of his experiment he was able to adhere to the diet and lose 6% body fat, going sub 10%. This is also coming from a world renowned nutrition coach and PhD in nutrition so he knew what to do and how to monitor it!








Surprisingly, there wasn't a big change in blood cell health markers. Some of his health markers improved as well BUT some of them slightly declined.








If you want to find out more you can read the experiment here:








https://www.precisionnutrition.com/intermittent-fasting/wrap-up-results-lessons








Which type is best for you?!








At the beginning of this I outlined 3 of the most popular IF strategies.








  • 16:8 in which you fast for 16hrs and you leave yourself with an 8hr window to consume your daily food intake.

  • The Eat-Stop-Eat (or 24hr fast once a week) where you do not eat for a full 24hrs then back to regular eating habits for the rest

  • The 5:2 Diet where you consume an extremely low amount of calories 2 days a week (500-600cals/day) then regular eating habits the rest of the week.








This is totally individual. You may prefer 1 type vs another. You may find 1 of the 3 is easier for you to adhere than the rest. If you've decided you want to give IF a shot I encourage you to try each method at least once and see which you prefer.