The Complete Guide to Intermittent Fasting for Beginners

Everything you need to know from how IF works to how you could fit it into your lifestyle

When it comes to health and fitness, workout is just 20% of the full picture while the other 80% will be our diet. To accomplish your fitness goal, you need to get your diet aligned with it.

I’ve had many fitness goals since I started paying attention to my health: losing fat, building mass, developing strength. You name it.

So, what’s my diet? Simple.I skip breakfast and eat only two meals each day. I have my first meal at around 1 pm, and the second and last meal at around 6:30 pm. Then I fast for 18 hours to 1 pm the next day.

You may wonder:

Isn’t it bad to skip breakfast?

Frankly, I thought so too. And because of that, I never really got started with intermittent fasting for many years. I used to believe that skipping breakfast was bad. But after some time of consideration and research, I decided to give it a try.

Surprisingly, my body fat dropped by 6% after three months with intermittent fasting and I see no negative effect on my energy level. I trained during my fasted state every morning with a bodyweight routine and saw a significant improvement in my strength, endurance, and explosive power.

Updated on June 2020: I stopped IF for a while in 2019 and got back to it a month ago. I fast for 18 hours in a day and eat in a 6-hour window. It's similar to the 16:8 daily fast schedule that you’ll learn more below.

I started intermittent fasting on-and-off (depends on goals) since 2015. My initial purpose was to lose weight and body fat, but then I dove deeper to understand other advantages and benefits of intermittent fasting.

Since this will be a lengthy article, here is a table of contents I prepared for you to navigate through each sub-category:

What is intermittent fasting?

Intermittent fasting (also known as intermittent fasting) has taken the Internet by storm. You see people sharing their journey of intermittent fasting on YouTube, at the same time, there are people who think it is dumb.

All kinds of debates have been going on about its practicality and effectiveness over the past few years. There is research that proves everything from the benefits of weight loss to promoting longevity, yet there are people who claim intermittent fasting is just another diet trend without sufficient evidence and proof.

This is a super-sized article about intermittent fasting borne out by my personal experience and some research. I’m not saying that it’s the best diet remedy that everyone should practice, but if you’re currently seeking more information about intermittent fasting to decide whether you should start implementing it, this is for you.

To make it clear, intermittent fasting is not a diet plan. It should be considered as a diet pattern. Rather than what you should and shouldn’t eat—like most diet programs available in the market—intermittent fasting is about when you should and shouldn’t eat.

Most diet programs suggest you eat either more or less of specific foods such as:

  • Atkins diet: suggests low carbohydrate.
  • Ketogenic diet: suggests high fat, low/no carbohydrate.
  • Paleo diet: suggests raw organic foods eaten by early humans.

But intermittent fasting is just like what it says: fasting. It doesn’t suggest increasing and reducing any specific food intake. You simply need to fast during a certain time frame by reducing your meal frequency with larger portions per meal.

In my case, I’m following one of the intermittent fasting variations to eat in an 8-hour window and then fast for the other 16 hours, every day. This might be hard for most people to accept since we have been taught that we need at least three meals a day, and the fitness industry then suggests that we have small portions but more frequent meals.

The truth is, fasting is being practiced by many others in different religions such as Judaism, Christianity, and Islam. There is proof showing that fasting was practiced and promoted by a few great philosophers and scientists throughout history.

I fast for greater physical and mental efficiency. —Plato
Fasting is the greatest remedy—the physician within. —Philippus Paracelsus
A little starvation can really do more for the average sick man than can be the best of medicines and the best doctors. —Mark Twain

How does intermittent fasting work?

Most people start practicing intermittent fasting with the goal of fat loss just like I did. So when talking about how it works, the first thing I’m going to explain is how it actually helps us to lose fat.

To understand how intermittent fasting works, you need to understand the difference between the fed state and the fasted state.

Our body is in the fed state when we’re eating and absorbing food. In most cases, the fed state starts from the time we eat (or a short period of time later depending on the portion) till three to four hours after we stop eating while we’re still digesting and absorbing the food we just ate.

It’s very hard for our body to burn fat during the fed state because while we’re eating and absorbing food, the insulin level in our bodies is high.

On the other hand, the fasted state occurs a few hours later, after our last meal when the food in our digestive system is completely digested and absorbed. During the fasted state, our blood sugar is low and so is our insulin level. Burning fat becomes easier when there is an absence of insulin in our bloodstream.

When we’re in the fasted state, our body can burn fat that has been inaccessible during the fed state.

With that said, we don’t usually enter the fasted state with the typical three-meal diet pattern. And that leads to a very minimum fat burning process happening in our body. This is one of the reasons why people who start intermittent fasting still lose weight without changing what they eat because their body is now getting into a fat-burning state which they usually don’t enter into.

Below is an illustration demonstrating the blood sugar level and insulin level in the typical three-meals diet pattern.

How intermittent fasting works - the fed state

And here is another illustration to show what happens to our insulin level with intermittent fasting.

How intermittent fasting works - the fasted state

Other benefits of intermittent fasting

Clearly, fat loss is one of the benefits of intermittent fasting. But it’s proven that intermittent fasting does more than just fat loss to our body.

1. Increase longevity

Scientists discovered long ago, that calorie restriction is a way to promote longevity. A sizeable portion of data supports the idea that limiting food intake reduces the risk of diseases common in old age and lengthens the period of life spent in good health.

But in recent years, researchers have focused on this strategy—intermittent fasting—as a promising alternative to calorie restriction. Which means you don’t need to continuously starve yourself to live longer.

The first cross research between calorie restriction and intermittent fasting was done way back in 1945 when it was discovered that intermittent fasting extends the lifespan of mice. You can read more about this here.

2. Reduce cancer risks and improve cognitive function

Besides living longer, there is also research claiming that intermittent fasting also reduces the risk of cancer, while at the same time: improve our cognitive function.

The theory behind this is that intermittent fasting acts in part as a form of mild stress that continually revs up cellular defenses against molecular damage.

3. Simplify your days

In my personal experience, this is the part I love most, probably because I haven’t lived long enough to experience what it means to live longer.

I’m a big fan of minimalism and the simplistic, and I prefer to put my focus on many important things in life.

I enjoy eating and don’t mind cooking, but at the same time, I prefer to read, write, make coffee, plan for my business, spend time with family, and go on vacations. Obviously, I’m not the one who prepares seven meals a day for seven days a week, I just don’t have time for that.

When the founder of Facebook, Mark Zuckerberg, was asked why he wears the same t-shirt all the time, his answer was gold.

There are many more important decisions I need to make, what to wear today is just not one of those.

That’s how I look at intermittent fasting. I will only have two meals a day, and they’re almost the same stuff (with my simple diet rule: good amount of protein and fibers, less refined carbs, and no sugar).For sure, this is way easier when compared to dieting.

Variations of intermittent fasting schedules and plans

Now you should have a better understanding about intermittent fasting, but how can you start? If you’re considering giving intermittent fasting a try, here are a few types of intermittent fasting plans you can follow.

Circadian intermittent fasting

We have evolved to be in sync with the day/night cycle which is known as the circadian rhythm.

We’re higher in energy and more active during the daytime and lower in energy at night. And our bodies and metabolism have adapted to eat during the day and sleep at night. Because of that, night-time eating is bad for our health, generally associated with obesity and diabetes.

The circadian intermittent fasting schedule is basically an eating plan based on the sunrise and sunset. You break your fast early in the morning when the sun comes up and have your last meal before the sun goes down and move into the fast. The feeding window is generally 11 hours with a fasting window of 13 hours.

Circadian intermittent fasting schedule

In fact, most of us are already doing this without noticing it. Fasting for 13 hours is normal to most people and that’s why the circadian fasting schedule is one of the best for beginners. If you just get started with intermittent fasting, the circadian fasting schedule is a good place to start.

You may not see a significant result if you already have a decent, healthy diet style. However, if you don’t usually pay attention to how and when you eat, this fasting schedule can be very helpful in adding an extra layer of awareness to your diet and help cut out unhealthy night-time eating.

16:8 daily intermittent fasting

As mentioned, this is a schedule to fast daily and this is what I practice most of the time. I first learned about this from Martin Berkhan‘s blog, Since he’s the one who popularized this intermittent fasting schedule, most people call this daily intermittent fasting schedule the LeanGains protocol.

In this daily intermittent fasting schedule, you will have a 16-hour fasted window and eight hours fed window. It doesn’t matter when you start your fed period as long as it lasts for only eight hours.

Right now, I usually start eating between noon to 1 pm and end my feeding period at around 7 pm to 8 pm. Personally, I find this suits me very well because I don’t want to miss dinner with friends and family. Besides, my family used to eat lots of carbs such as rice and noodles during breakfast (Asian culture). By skipping my breakfast, I can avoid consuming too many carbs throughout the day.

16:8 daily intermittent fasting schedule

Note that you don’t need to change what you eat when you start practicing intermittent fasting. For my case, I started to reduce my carb intake in 2010, long before I started practicing intermittent fasting.

The best part of this 16:8 daily intermittent fasting is that you’re practicing it every day. It’s easier for you to plan ahead and slowly make it your diet pattern. It’s more likely to become a habit for you compared to other intermittent fasting schedules where you only do it once a week.

But remember that you’re not cutting off the caloric intake of a meal, you’re just changing your meal frequency and eating time frame. With that said, you will need to up your portion for the two meals you do have in a day.

For me, I increase the lunch portion slightly, and then I add a snack—usually green juice—in between my meals. It helps to replace the calorie intake of my breakfast and bump up my micronutrients and fiber intake.

5:2 intermittent fasting (weekly)

During the early stages of my intermittent fasting journey, I read some books and did research online to learn more about this practice. One of the books I read was The Fast Diet by Dr. Michael Mosley and Mimi Spencer.

The book covers lots of scientific studies and research on intermittent fasting. It’s a great resource if you’d like to know more about the benefits of fasting.

This fasting schedule is a little different from 16:8 intermittent fasting. Instead of fasting every day, Dr. Michael Mosley proposes to fast for only two days a week (you can do less if you’ve just started, or do more days if you feel good about it).

You’re allowed to eat during your fasted days, but in very low calories, suggested 600 calories for male and 500 calories for female.

5:2 weekly intermittent fasting schedule

The biggest advantage of this intermittent fasting is that you don’t need to do it every day. And you’re allowed to eat whatever you like during your non-fast days. Also, you see results in fat loss, extended longevity, and a lower risk of diabetes and cancer. Personally, I think you should still maintain a balanced, healthy diet for best results.

I don’t practice this schedule personally due to the necessity of counting calories during the fast days. But it’s good for anyone who just started with intermittent fasting and would never think of doing it every day.

Alternate day intermittent fasting

Now you have a clearer picture of daily and weekly intermittent fasting schedules, here is another more intense way to practice intermittent fasting. In the alternate day intermittent fasting schedule, your feeding period will last for 24 hours, and then you will need to fast for 24 hours.

Just like the daily schedule, you can pick the time that suits you most. In the illustration below, your first meal starts at 8 pm, and you’re allowed to eat for the next 24 hours till 8 pm the next day. After which you will need to fast for 24 hours from 8 pm to 8 pm again the next day.

Alternate day intermittent fasting schedule

The extended fasting time frame allows your body to stay in the fat burning state longer compared to a daily and weekly intermittent fasting schedule. But it’s more challenging because you need to abstain from food for 24 hours. This will become very challenging for people with an active career or lifestyle.

I personally find the most challenging part is not during the fasted period, but the fed period. In order to compensate for the calorie intake during your fasted period, you will need to eat more during your fed period. Even though I am practicing 16:8 daily schedules, I still find it hard to take a big portion of a meal at once, that’s why I incorporate green juice into my diet between my first and last meal.

Practicing alternative day intermittent fasting means that you will need to chuck down all the food to meet the total calorie requirement for two days within 24 hours, if you never want to suffer from significant weight loss and muscle loss.

If eating a big portion of food every three to four hours isn’t a problem for you, you can definitely go for this intermittent fasting schedule.

36-hour (or longer) intermittent fasting

There are periods when I stop doing daily intermittent fasting in the past few years, especially when I want to make bigger progress in strength training.

However, I still want to reap the benefits of intermittent fasting. Thus, I started to research and experiment with longer fast (36 hours or more) biweekly or monthly.

Longer intermittent fasting schedule

Anyway, longer fast has more complications to it. I would not recommend you try it without a physician’s advice. Remember: if you do not feel well at any point, stop the fast and start eating. You can feel hunger, but you shouldn’t feel sick.

Personal experience with intermittent fasting

Now, here is my personal experience intermittent fasting since 2015. I did cover some of these above but I think I should share this in a more organized format here.

Why did I start?

The reason I started intermittent fasting is simple: To lose fat.

I find it difficult to lose fat unless I go hard into a crazy bodybuilding style strict diet, even after I switched to a low-carb diet. Since I’m not a bodybuilder, and those diet patterns are very hard to sustain, I stay in low carb (and avoid refined sugar at all costs) and start practicing intermittent fasting.

It helps me to lose fat in two ways:

  • First is what I just explained above about our insulin level.
  • Second, I ate less junk food after I got into intermittent fasting. This then reduced the chance for me to overeat (that leads to calorie surplus).

How I got started? What were the initial results?

I heard about intermittent fasting in 2012 before I started practicing it from an Australian friend of mine named Jamie. I did some research on how to do it before I got started. I think the LeanGains (16:8) method suits me the most with my lifestyle, habits, and daily activities.

After practicing intermittent fasting for three months, I lost 6% of body fat, from 24% to 18%, then the progress slowed down.

What I learned here is that intermittent fasting is not a magic eating pattern, you still need to slowly adjust what you put in your mouth to see the best results from it. Having all junk food for eight hours then fasting for 16 hours won’t bring you the lean body shape (and other benefits) you want.

What am I eating?

I had been practicing low-carb diets long before intermittent fasting. So, I eat mostly what I used to eat—lots of protein from chicken breast, fish, beef, and eggs, many vegetables, and some fruits and nuts.

Personally, I found green juice is the best way for me to boost my fiber intake rather than having a super-sized portion in my meals.You can learn more about this part at

How to make it stick?

There are two strategies I’m using to make intermittent fasting sticks.

It might be hard in the beginning for you to skip breakfast or dinner, or starve for a certain period depending on which schedule you’re practicing. To make sure you don’t eat during your fasted state, stay away from food.

Second, plan ahead. I make my food choice ridiculously simple where I need not think about what I want to eat most of the time. Make it a habit of making healthier food selections, and when you meal time comes, you will default to those diet habits.

I believe in making small progress and I don’t force myself to go 110% into anything, especially for things that require a certain period to see results (health, business, relationships).

I practice sustainable behaviors 90% of the time and have 10% freedom over things. So, if I decide to have breakfast with my family or go for a drink session with friends someday, I feel no guilt for that. But remember, make it only 10% of the time.

The best part of intermittent fasting?

One reason I like intermittent fasting is because I default myself to healthier foods because of the short eating timeframe. I can only have two meals a day, so to have junk food for lunch means my diet is 50% crap for that day.

Another benefit of intermittent fasting is something I mentioned above: It makes my day simpler. I think less about what to eat, where to eat, and instead, spend more time actually eating.

It’s even simpler when I compare this diet pattern to what I used to do when I was in the strict diet plan. I spend less time to cook, less effort to force myself to eat what I don’t like.

Intermittent fasting books and tools

If you want to dive deeper into the topic of intermittent fasting on our own, here are five books I recommend you to check out:

  1. The Complete Guide to Fasting by Dr. Jason Fung and Jimmy Moore
  2. A Hermit's Cookbook: Monks, Food and Fasting in the Middle Ages by Andrew Jotischky
  3. The Fasting Cure by Upton Sinclair
  4. Eat Stop Eat by Brad Pilon
  5. The Fast Diet by Michael Mosley and Mimi Spencer

To help you get started quickly, here are three intermittent fasting apps you can use to track your fasts based on your selected schedule:

Other concerns and FAQs

Which is the best way to practice intermittent fasting?

It depends on your lifestyle, daily activities, and surroundings. There are advantages and disadvantages for each fasting schedule. Know your goal and purpose of practicing intermittent fasting.

I suggest you start with weekly or daily intermittent fasting first, give yourself time to adjust and see which works best for you.

Is intermittent fasting for everyone?

No. Even with the benefits I mentioned above from fat loss to promoting longevity, I don’t think intermittent fasting is for everyone. You still need to give it a try before you know if it suits you.

When I say it’s not for everyone, I’m not talking about the practical challenges. What I suggest  is to focus on the result of the overall biochemical effects of intermittent fasting and what it does to one’s body.

Is intermittent fasting suitable for women?

It hasn’t worked well for my wife. But frankly, I don’t know.

I have quite a good experience with intermittent fasting but my fiance didn’t when I  introduced this to her. I did read about some case studies and testimonials of female intermittent fasting practitioners from The Fast Diet.

Feel free to get a copy of this book to know more or you can go here – all female Facebook page and group where they discuss intermittent fasting.

Am I going to lose muscle?

I did experience a minor amount of weight and muscle loss when I just started due to the calorie deficit because I was not eating big enough portions during the fed period. By the way, I’m fine with it because my sole purpose during the initial stage was fat loss, I was ready and prepared to lose some weight and muscle during the process.

If you really want to avoid muscle loss, I’d recommend you schedule your training in between meals so you don’t miss the energy/protein compensation window after a workout session.

Is this the ultimate magical way to lose fat?

Again, no, this is not. If you search for intermittent fasting online, it’s very unlikely for you to find crazy and unrealistic promises from this diet pattern. Intermittent fasting simply creates the biochemical effect of putting our body into the fat-lose state but every person reacts to it differently.

Besides, you will still need to keep a balanced and healthy diet with an active lifestyle to gain the best results from it. You can’t eat crap with any fasting diet here and expect miracles  (even if some articles said so).

Ready to give intermittent fasting a shot?

I’ve outlined the complete guide to intermittent fasting for beginners. Note that I’m not a professional nutritionist or dietitian. Everything I’ve mentioned above is based on my personal research and experience.

If you’re considering intermittent fasting, I hope this guide helps you make a more informed decision. It could also be helpful if you’re at the beginning stage of the intermittent fasting practice.

Feel free to share this with anyone you think who needs to read this.


  1. I had included almost everything I need to say in the article. Rather than linking the resources at this footnote area, I prefer to link them in the article because it’s just too long for you to scroll to this part back and forth. To end this, here is a YouTube video I found interesting – How To Eat: Like Predator or Prey?
  2. Feel free to read more about the differences between the Eat Stop Eat IF protocol and the LeanGains IF protocol here.
  3. Here are three more YouTube videos about fasting by What I’ve Learned (One of my favorite YouTube channels): (1) Longevity and fasting, (2) Intermittent Fasting and Hunger, and (3) Intermittent Fasting and Sleep.

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