[Guide] Intermittent Fasting for Fat Loss

by | Apr 21, 2020 | Lifestyle, Nutrition

Have you ever played the game “Never Have I Ever?”

Did you play in high school with your friends?

How about in college with your roommates?

Or now, in all the Facebook, Instagram, and Tik Tok games going around to occupy our time during quarantine.

Let’s play a round real quick….

Never have I ever tried Intermittent Fasting.

My guess is a lot of us are putting a finger down…

Intermittent Fasting has become quite a popular dieting tactic over the last decade, but believe it or not, this protocol expands over centuries.

If you take a look back at our hunter and gatherer ancestors, intermittent fasting was a regular practice since food availability greatly fluctuated.

Then, various religions have practiced fasting to serve their religious beliefs for centuries.

But just because intermittent fasting worked for our ancestors and fit our religious beliefs does not make it the key to fat loss or weight maintenance.

Just like any diet or nutrition protocol, it needs to be the right fit for YOU, and the only way to know if it’s a fit is to understand the in’s and out’s of it.

So let’s dive right in…..

What Is Intermittent Fasting?

According to Harvard University T.H. Chan, Intermittent Fasting is as the following:

“A diet regimen that cycles between brief protocols of fasting, with either no food or significant calorie reduction, and periods of unrestricted eating.”

In simpler terms, intermittent fasting is a broad term that refers to a variety of fast-feed windows.

Time Restricted Eating (TRE) falls under a separate category of eating and fasting; however, I find most referring to intermittent fasting are actually following a time restricted eating pattern.

When it comes to my clients and for the sake of this blog, we will consider intermittent fasting a type of time restricted eating.

Let’s get into this a bit more…

This means food is consumed in a specific time of the day and food is restricted in the other time of day.

Although it is not technically a diet, intermittent fasting has grown in popularity as a diet or source for weight loss for the general population. However, the major drawback from this as a weight loss strategy is that there are no specifications on calories, macros, or foods to eat, but only on times to eat.

How Does It Work?

There are a number of styles of intermittent fasting, but there are 3 that I find most beneficial and doable for clients.

The Lean Gains Approach

Fast/Feed Window: 16 Hours to 8 Hours

Implementation: Experience shows The Lean Gains Approach is best applied by starting with a 12/12 fast/feed window, then expanding to a 14/8, and eventually to a 16/8 approach. This approach can be utilized more frequently, and most find it beneficial to use daily.


10:00 AM – Breakfast

12:30 PM – Lunch

2:30 PM – Snack

5:30 PM – Dinner

6:00 PM to 10:00 AM – FAST

The Warrior Diet Approach

Fast/Feed Window: 20 Hours to 4 Hours

Implementation: Similar to The Lean Gains Approach, clients are most successful working up from a 12/12 fast/feed window up to a 20/4 window. The Warrior Diet Approach is a bit more extreme, and likely means meal sizes are much larger to meet adequate calorie needs. In my experience, best adherence and consistency when practiced only 2 to 4 times per week.


Option 1

10:00 AM – Meal #1

12:00 PM – Meal #2

2:00 PM – Meal #3

Option 2

1:00 PM – Meal #1

2:30 PM – Meal #2

5:00 PM – Meal #3

Option #3

4:00 PM – Meal #1

6:00 PM – Meal #2

8:00 PM – Meal #3

The 24-Hour Approach

Fast/Feed Window: 24 Hours to 0 Hours

Implementation: The 24-Hour Approach gain works its way up from a 12/12 window all the way to a 24/0 window. The 24-Hour Approach is one of the more extreme examples of intermittent fasting. It should be noted that the calories ‘skipped’ on a fasting day, must be made up throughout the remainder of the week, for forgoing those calories puts you at risk for nutrient deficiencies and hormonal irregularities. Due to the intensity of the 24-Hour Approach, this should only be utilized 1 to 2 times per month.


Day 1: Eat Nothing

Day 2: Eat 

Does It Work?

Now, the style and schedule is important, but you’re probably wondering, “Does it even work?”

There are two things to note before we really dive into this question:

  1. No single diet plan works for EVERYONE because everyone is different.
  2. Calories In vs. Calories Out is STILL #1 and matters above all else.

Many times, the fast/feed window reduces someone’s daily caloric intake because it limits day grazing and possibly even one to two meals. This puts individuals into a caloric deficit, and as you know, any diet that creates a caloric intake will lead to fat loss.

But let’s get into the research…

Because intermittent fasting is fairly new as a weight loss protocol, published research is still up and coming.

The first study was published in 2016, and assessed the effect of intermittent fasting on participants in their 20s and 30s with a minimum training experience of 5 years. All calories and macros were tracked by participants, but were divided into two groups:

  • Group #1: Ate calories in an 8-hour window
  • Group #2: Ate at an evenly spread meal frequency across the day.

Other important variables include:

  • Both groups followed a high protein diet (0.8-0.9 grams/#)
  • Original calorie prescription was maintained throughout the study
  • Both groups followed a 3x/week full body training program of the same exercises, sets, reps, and intensity.

Researchers found that Group #1 (Intermittent Fasting Group) lost 3.5# more than Group #2 (Non-Fasting Group). It was also found that the hormone “adiponectin” was increased in Group #1 but not #2, which likely caused the fat loss difference because of its effects on the brain as an increaser of energy expenditure.

There are two important factors to consider with this study:

  • The study only lasted 8 weeks, which isn’t truly long enough to assume either short-term or long-term hormonal changes.
  • Group #1 was in a 200-calorie deficit, which is by no means a MAJOR deficit, but is enough to drop body fat.

While, there are some limitations to the study, it does show that intermittent fasting does have some influence on weight loss, albeit no confirmation of its superiority to a traditional diet or caloric deficit.

Beyond its effectiveness as a weight loss protocol, research has found a number of physiological benefits, check them out:

Weight Loss – This is what gives fasting its notoriety, but it is important to note that the simple act of fasting does not lead to weight loss, but it does make it easier to adhere to a caloric deficit on a daily or weekly basis.

Metabolism Increases – Research does show fasting to boost metabolism with effects being more significant the longer the fast. This is due in large part to the body’s natural hormonal boosts, improved insulin levels, and its natural survival mechanism.

Cell Repair – During a fast, your body looks to get rid of dead cells or any unnecessary waste inside of cells, so the body can dedicate its efforts to repairing and rebuilding new and stronger cells.

Longevity & Disease Prevention – Fasting can spark gene expression, which is the body’s change in genes, cells, and molecules related to life span and disease prevention.

Heart Health – Various studies show fasting to improve cholesterol, triglycerides, blood pressure, and inflammatory markers.

Stress & Inflammation – Oxidative stress and inflammation in the body have been shown to improve after following intermittent fasting.

Gut Health – Because of the anti-inflammatory effects of fasting, there are many links to improved gut health in its aid in digestion and protection of gut bacteria.

Cancer Prevention – Fasting has been shown to help in the regeneration of cells, which has potential to aid in the prevention or management of cancer.

Insulin Levels – Fasting is widely known for its ability to improve insulin sensitivity, which is related to losses in body fat and lesser storages of body fat from consumed food.

Growth Hormone Levels – Research suggest fasting to boost growth hormone levels, which is great for the regulation of body composition, body fluids, muscle and bone growth, sugar, and fat metabolism. All of these are related to more muscle and less fat.

Testosterone Levels – Research also suggests a boost in testosterone levels for men as a result of fasting due to the help in sensitivity of the androgen receptors.

What Are the Negatives?

While fasting does have plenty of benefits, there are some negatives or risks associated with fasting.


Although fasts allow water, your overall fluid consumption is diminished because you are not taking in any fluids from food. This potentially puts one at risk for dehydration.

If you’re somebody who becomes easily dehydrated, water needs to be your primary focus during a fast. For these people, and anyone fasting really, I recommend adding a bit of salt to your water to aid in water retention and maintenance of an electrolyte balance.

Hunger & Adherence

Sometimes people get so excited to test out intermittent fasting that they neglect to truly understand the length of a fast.

16 hours is a long time, which means any fast beyond that time frame is a REALLY long time.

You’re going to be hungry during a fast!

But the truth is that some of us just don’t handle hunger very well, which significantly hurts our ability to adhere to a fasting protocol. Regardless the dieting protocol, the key is adherence, so if you love to eat breakfast first thing in the morning, fasting into the morning is probably not the right strategy for you.

History of Eating Disorders

Certain populations are not fit for fasting because of their dietary history; one of those populations being individuals with a history of eating disorders.

The lengthy fast and ensuing hunger for an individual with a history of binge-eating has a greater chance of reverting to those binge-eating behaviors upon conclusion of a fast. Fasting sparks a great deal of hunger as well as emotions, which is not an ideal scenario for a former binge-eater.

On the other hand, an individual who formerly struggled with anorexia nervosa is less than ideal for fasting. A fast is another form of restrictive eating; therefore, increasing the likelihood of an anorexic to fall back into a pattern of restricting food in an unhealthy manner.

Muscle Building

Fasting does 3 things that potentially hinder someone’s ability to build muscle:

It takes away a major chunk of your day for calorie consumption, thus making it more difficult to be in a caloric surplus.

On a similar note, fasting limits your ability to get adequate protein, which is critical for muscle recovery and growth. If you do choose to fast, then adequate protein intake evenly spread throughout the day must be a primary focus during your feeding windows.

Fasting can trick your body into thinking it’s in a dieting state, which hurts you if you’re actually trying to gain muscle. Growth hormone and testosterone do not increase until the fast is over, but cortisol increases, and that combination is one that stalls the growth process.

What Breaks a Fast?

Aside from the effectiveness of fasting, one of the most heavily debated topics is what breaks a fast.

The answer: It depends on who you talk to….

Certain doctors, researchers, or religious leaders state that consumption of anything other than water breaks a fast because of its impact on the body.

“But what about my coffee?”

A collection of research suggests that black coffee (yes, absolutely plain) does not trigger an insulin or glucose response. In addition, most of this research suggests coffee to actually boost the autophagy (the body’s ability to flush or clean out damaged cells) response.

The standard and accepted rule of thumb as to what breaks a fast is that anything containing a significant amount of calories breaks a fast. This includes BCAAs, EAAs, fish oil, supplements, or any water, coffee, or tea additives.

Is It Right for You?

So you’ve done all this reading, but maybe you’re still wondering if intermittent fasting is right for you. Let’s address the two populations most likely reading this blog.


Okay ladies, we hear it all the time – we’re more sensitive. Whether or not that be true when it relates to emotions is up to your mental and emotional make up; however, when it comes to fasting, it is absolutely true. Women have been shown to have less resilient hormones and are more sensitive to the stress of fasting in comparison to men. As a result, this can exacerbate any underlying hormonal issues.

What this means is that women’s hormones need more attention and balanced energy (calories) to maintain an appropriate hormonal balance.

If you’re a female who knowingly or even thinks you might suffer from a hormonal imbalance, then fasting is not an ideal protocol for you until your hormones are well-balanced.

It does not mean women can NEVER fast, in fact, I personally as well as some clients have seen incredible results from fasting, but the additional stress of a fast can make PMS symptoms and adrenal dysfunction worse. Let’s be honest, does anyone want a worse period?

High Stress & Poor Recovery Individuals

Now, we all face stress, but if you’re someone who has serious stress issues, suffers from adrenal fatigue, or don’t fully recover from your daily activities, then fasting is not presently the best option for you.

The reality is that if you fall under one or more of those classifications, you’re hormones probably are not going to respond well to fasting.

It’s not to say you can never fast, but during this time and until your hormones are properly balanced, your priority needs to be balanced nutrition consisting of majority whole and minimally processed foods.

If this is you, and you’re looking for a nutrition protocol until stress or recovery is better managed, try these things:

  • Spread protein evenly across all meals.
  • Get extremely beneficial fat sources in DAILY (fatty fish, eggs, coconut oil, and tree nuts)
  • Eat a variety of veggies and a lot of them
  • Be sure to get at least 1 serving of fruit per day

If you need more help setting up a plan to help balance your nutrition until you’re ready to try out fasting, CLICK HERE for a FREE Nutrition Strategy Call.

How Can You Start?

You’ve read all you need to know about fasting and you’re ready to get started, so how do you do that?

In my experience, I find 2 strategies to be successful when getting into fasting.

Off-Day or Light-Training Day Fasts

In this strategy, identify your non-training or light-training days and fast anywhere from 16 to 24 hours. Start with 16 hours and add on 2 hours each time you repeat the fast.

Gradual Fast

In this strategy, start by setting a 12-hour feed window, and by default you will also be fasting for 12 hours.

Repeat this for anywhere from 5 to 7 days, then subtract 2 hours from your feeding window and add those 2 hours to your fasting window. This puts you into a 14/10 fast-feed window, and does become more of a stretch.

After another 5 to 7 days, subtract another 2 hours from your feeding window and again add those to your fasting window. Now you’re in a 16/8 fast-feed window, and further limiting your feeding window.

If you desire a longer fast, you can repeat this strategy until you’re at your ideal fast-feed window.

When it comes down to it, fasting works.

But so does every other weight loss protocol if you create the optimal caloric deficit for weight loss.

Does intermittent fating pose many health benefits?


Does it also pose some negatives?

Of course.

The important thing to remember about any diet is that it must fit to you and your lifestyle! Adherence is the key to success, so if you think intermittent fasting is a protocol you can adhere to, give it a shot! You won’t know until you try!

About The Author

Jordan Davies is the Co-Owner of Complete Performance. Jordan has her B.S. in Exercise Science and Psychology, and her M.A. in Holistic Health Studies. She is a CSCS certified strength and conditioning coach, and a PN-1 and NCI-1 certified nutrition coach. She loves to study how the human body needs to be moved and nourished and making that fit to your unique lifestyle. Click Here Now to Apply for Coaching with Jordan.

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