Intermittent Fasting – What Is It And How Does It Work?


Written by Philip Stefanov

Philip Stefanov is a Fitness Writer, Blogger, Certified Personal Trainer, and the Founder of He has spent the last eight years writing fitness content and training men and women in the gym, as well as online.

July 10, 2022

Introduction – Intermittent Fasting – What Is It And How Does It Work?

From a once-obscure nutritional approach to one of the leading health tactics, intermittent fasting has grown in popularity over the years. 

These days, people claim that fasting brings many benefits, helps us live longer, and promotes weight loss.

But, what exactly is intermittent fasting, how does it work, and what specific benefits can we expect? Let’s dive in and break it down.

What is Intermittent Fasting?

Intermittent fasting, also known as IF or fasting, is a popular nutritional approach. Unlike diets that dictate what you should eat, fasting only tells you when to eat and fast. In other words, fasting isn’t a diet but an eating pattern.

One of the most popular fasting protocols is the 16:8 approach, where you fast for sixteen hours per day and eat your day’s calories inside an eight-hour window. A simple way to apply the 16:8 protocol would be to skip eating in the morning, break your fast at noon, eat dinner at 7 or 8 pm, and fast until noon the next day. Many people who skip breakfast follow a modified fasting schedule without realizing it.

Eat Stop Eat is also a popular method popularized by Brad Pilon. The objective is to complete one or two 24-hour fasts each week and follow a regular eating schedule for the rest of the time. For example, you can eat as you usually do from Monday to Friday, fast for 24 hours, eat only dinner on Saturday, and resume your normal eating for another six days.

The approach works well for weight loss because it makes it easier to control your calories without following a diet or tracking your food intake. You can introduce a second 24-hour fast during the week to make quicker progress.

Why Would Anyone Consider Intermittent Fasting?

A notable reason you might consider intermittent fasting would be to introduce some structure to your nutrition. Many people fall for mindless eating, often consuming hundreds or thousands of calories due to boredom. Others seek comfort in food, leading to unwanted weight gain, health problems, and a poor relationship with food. 1, 2, 3

Forcing yourself to avoid all calories for a specific period is an excellent way to better understand your hunger and satiety and determine how much food you truly need to consume.

Another reason for considering IF would be to simplify your day. Instead of thinking about food from the moment you wake up, you can enjoy a few hours where you don’t have to spend mental energy on what to eat and when. As a result, you can dedicate your time to work, study, or something else.

How Does Intermittent Fasting Work?

Intermittent fasting is nothing special. You still need to be mindful of your calorie intake and consume whole and nutritious foods to reap the associated benefits. 4, 5

The eating patterns work by restricting your calorie intake without having to go on a diet, count calories, or use another of the many complex tactics. All you have to do is adhere to your fasting and feeding windows to reap most IF benefits.

What Benefits Does Intermittent Fasting Bring?

It Promotes Weight Loss

People utilize intermittent fasting to lose weight, often believing it possesses magical properties. The truth is, fasting is not a magic fat loss bullet 6. What matters most is that you establish and maintain a calorie deficit––consuming fewer calories than you burn 7. As a result, your body has no choice but to start breaking down fat and lean tissue for the remaining energy it needs to function.

Fasting can help because it makes it easier to stick with the necessary caloric restriction. Eating all of your daily calories within a few hours allows you to have larger and more satisfying meals, making you feel like you’re not even on a diet.

It Can Improve Various Health Markers

Research links intermittent fasting to several health benefits. 

Most notably, fasting can lead to fat loss, which is beneficial for reducing the risk of cardiovascular and metabolic disease. 8, 9 Fasting also leads to drops in insulin levels, giving your pancreas a break and reducing the risk of metabolic conditions.10

Some research also suggests that fasting promotes cell repair and can stimulate autophagy––a process where your body cleans itself of old and damaged cells. 11

Fasting can also lead to higher growth hormone levels, which brings about certain health benefits. 12

It Might Help us Live Longer

Caloric restriction has been linked to longevity for a long time. For instance, the Japanese have a rule of eating until they are 80 percent full––Hara Hachi bu or eat until you are eight parts full. Unsurprisingly, they are also one of the nations with the longest average life span of 84.9 years as of 2022. 13

Of course, suggesting that their eating rule is what dictates their longevity would be silly. But, it certainly contributes. 

Intermittent fasting is a tactic for lengthening one’s life because it can activate the same mechanisms that work during caloric restriction. The exciting thing is that we might not necessarily have to be in a calorie deficit to experience these effects. 

Human research in the area is yet to come out, but some rodent research finds that intermittent calorie restriction lengthens the life of subjects . 14, 15

It Can Reduce Cancer Risk

The problem with cancer is that it can come in many forms and for various reasons. It’s important to note that the evidence isn’t conclusive, but early findings suggest that fasting can lower our cancer risk.

For example, in one review from 2007, researchers noted that intermittent fasting could reduce cancer risk. 16 Various animal models suggest that fasting can lower the risk of some cancers, prolong survival after diagnosis, and reduce the rate of cancer cell growth for certain types. 


Intermittent fasting has grown in popularity, and for good reasons. The nutritional approach simplifies your day, adds much-needed structure, and offers numerous health benefits.

Fasting is not the magic bullet some people claim it is, and we certainly need more research before concluding. But, data and anecdotal evidence suggest that it can be a tremendous nutritional strategy for numerous reasons.

Featured Image Credit: Photo by Nathan Cowley on Pexels


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