Intermittent Fasting – The (Ultimate) Ultimate Beginner’s Guide

I’m one of those – always on a diet – people.  I admit it.  Ever since I was an awkward hormone-raging teen I’ve struggled with my weight. I’ve tried countless diets. I’ve dabbed at Atkins, Mediterranean, Soup, SlimFast, Herbalife… the list goes on. You name it – I’ve probably done it.

And the truth is… I’ve had significant results with (almost) all of the diets I’ve tried. And yes – I’ve found the elusive fitness unicorn; I’ve worn a sick-pack on my belly.

The problem is… life gets in the way.  Maybe it’s a ski (cross that – snowboarding) trip with my college buddies. Or… two people fall in love and want to celebrate with expensive champagne and delicious food.  Ahhh – the wedding season. Isn’t it lovely? Well, a few months later, you have the binge-eating holiday people call Christmas. You know why Santa is so chubby? It’s because he stuffs his face with all the sugary holiday delights. And so do I!  I feel you, 🎅. 😉

And so… a vicious cycle begins – one I’ve known too well.  I over eat a few times. After a while, this – of course makes me gain weight.  I feel bad about it. And what do I do? I figure “what the hell I’m kinda sad”. Maybe I’ll feel better if I grab that warm cookie from off the counter. Guess what? That doesn’t make me feel better at all. So the next day I eat some more.

(Does any of this sound familiar?)

So, when spring comes I’ve usually packed a few pounds. And like the snow on a sunny April day, my six pack melts away. And you know what? It’s excruciatingly tough to make it come back. After a while, all my previous efforts are gone. I’m back to overweight status.  This downward cycle goes something like this.

To top it off, as the years go by, losing the extra weight gets tougher and tougher. ARGGGGG!!!



Eventually… it gets to a point where I have to do something about it. And I start dieting again. I’m off to the next fad diet out there.

I thought I was doomed to a life of weight fluctuation – going from fit to chubby and vice-versa.


Then one day… I found out about Intermittent Fasting (I.F.).


Inter… WHAT?

Intermittent Fasting (I.F.) is a diet. Well, technically it’s an eating pattern ’cause it doesn’t tell you WHAT to eat – but WHEN.

To put it quite simply – it’s when you eat stuff. Then you don’t. Then you eat some more. Then you… Well, you get the point.


Hold on – don’t I do that already? Like when I am asleep?


Yeah, you do. But I’m talking about more than just your beauty sleep, buddy! There are many different variations (which we’ll discuss later on) but Intermittent fasts can last up to 36 hours and more.


And that’s WITHOUT losing your mind (or killing someone ’cause you’re too hungry). It can be done, I assure you. I’ve been fasting for more than 14 hours as I write this and I feel as sane as I’ll ever be. And my wife is alive and well – BTW. 🙂

But how does Intermittent Fasting actually work? And how can it help me lose weight?


Glad you asked, ma’ friend! When you fast for longer periods of time several things happen – the main one being you lose weight.

For all of you, science nuts out there: here’s a slightly more detailed explanation of how it can help you do that. (There are other benefits as well, which we’ll cover later on.)

If you are not the “sciencey” type, by all means, click here to skip this part.

(Takes a deep breath.) Okay. Let’s start by understanding the difference between the fed state and the fasted state.  It’s simple. You’re in a “fed state” right after you eat. When you haven’t eaten something in a while, you enter the fasted state.  As is expected, your body (the highly efficient machine that it is) treats both states very differently.


While on a fed state, your insulin levels increase. (Insulin is a hormone produced by the pancreas whose function is to help your cells store future energy in the form of glycogen or fat). And that’s exactly what it does. Once your glycogen tanks are filled up, the excess energy is stored as fat and shows up in the most inconvenient places (I’m talking to you, love handles).

When you enter the fasted state (typically 12 hours after you eat) your insulin levels decrease. Your body is concerned it won’t be getting any more energy for a while. Your body doesn’t want that… and in order to continue functioning properly, it needs to find an alternative energy source.

Well, hello there FAT. Fat now becomes your body’s main source of fuel. And you’ve just switched from storing excess fat to BURNING excess fat.

What an exciting turn of events, right?

Check out the illustration below to review what we’ve learned so far.


There is also another (more obvious) reason why you’ll lose weight: a calorie deficit.  Assuming you eat normally after you fast (not binging on ice cream and bacon – I know it’s tough) you will have consumed fewer calories than usual. If you burn more calories (by exercise or normal body functions) than you put in, you will naturally lose weight. This is the basis of most of the diets out there, including the Intermittent Fasting protocol.

Okay – losing weight is a pretty cool benefit of Intermittent Fasting! Are there any other health benefits?


Hell yeah – there is research (and anecdotal data) to support that Intermittent Fasting:

Increases mental clarity, concentration and energy levels

A 2013 study found that fasting “was frequently accompanied by an increased level of vigilance and a mood improvement, a subjective feeling of well-being, and sometimes of euphoria”.

This sounds counter-intuitive, right?  Many people get cranky when they are hungry. (I’m talking to you, wifey). But if you think in evolutionary terms, it actually makes perfect sense. When food was scarce, our ancestors needed to step up their mental game to survive. They needed the extra boost of adrenaline to look for food. In my personal experience, I’ve found that once I get over the initial hunger pangs, I actually start feeling super pumped and ready to tackle my ever-growing to-do list.


Lowers cholesterol and sugar levels in the blood

In 2011, a team of research cardiologists found that fasting can contribute to lower overall cholesterol and sugar levels, i.e., it decreases your chance of having a heart problem in the future. This study was conducted on 200 individuals, both patients and healthy individuals.

Increases growth hormone (HGH)

The same study found that while on a 24 hour fast, the subjects increased the production of HGH an average of 1,300 percent in women, and nearly 2,000 percent in men. This is important because HGH “works to protect your lean muscle and metabolic balance”.

May extend your life

In February of 2015, researchers from the University of Florida conducted an interesting study. They put 19 people on an alternate-day fasting program for 3 weeks and measured all kinds of markers. The results? Subjects began producing more copies of a longevity gene known as SIRT3 which improves the cell’s abilities to repair themselves as well as protects it against damaging free radical molecules. Here’s another study with similar results.

Reduces  inflammation

Some studies (here, here and here) suggest that Intermittent Fasting can reduce inflammation, a key driver of all sorts of common diseases such as Asthma, Cancer and Alzheimer’s disease among others.

Helps fight Cancer

This 2015 study suggests that Intermittent Fasting lowers systemic inflammation and subsequently is able to reduce breast cancer risk. In this other study. I.F. reduced blood glucose and IGF1- levels reducing the risk of getting Cancer.

Other benefits of Intermittent Fasting

As if the and weight loss and other health benefits weren’t enough – there are MANY other advantages to Intermittent Fasting. Continue reading to find out.

It’s  Simple.

One of the main benefits is its sheer simplicity. You don’t have to memorize a new diet. You don’t have to count calories on your food log or take your carefully weighed lunch to work every day, either. Wouldn’t it be great to simplify your life, for a change?

It’s Cheap

In fact, it doesn’t cost you a thing. You actually save money by not having to buy food. ‘Nough said.

It saves you time

You have more free time (to do other stuff). Imagine the time you’ll save cooking fewer meals per week or all the times you won’t have to swing by the restaurant and get your take-out.

You’ll have more willpower.

Every time you successfully complete a fast you’ll be reminded of how strong you really are. The feeling of accomplishment will make you proud of yourself and you’ll be ready to face other life challenges. 💪

You’ll appreciate food more.

Never again will you stuff a bag of Cheetos while binging on the latest episode of your favorite Netflix Show. You will learn to appreciate food. You’ll make every bite count.

Sound cool! Anybody I know who’s doing it?










(This meme comes from the 1994 film LEON:  The Professional. If you haven’t seen it, stop reading and go watch it right now. This post can wait. Trust me.)

Just kidding. NOT everyone fasts. But there ARE a lot of people doing it.

You have regular ‘ole folks like me. And also mega-celebrities like Dwayne “The Rock” Johnson and the shredded Wolverine, AKA actor Hugh Jackman (check out his interview here).

Truth is – our fellow humans have been doing it for thousands of years. Some did it (and still do) for religious reasons. Some did it for medical reasons (think Ancient Greece). And some did it  ’cause they just couldn’t find a reliable food source.

Ok, It’s true – our mammoth-hunting ancestors would be scratching their heads – like WTF – but it’s tough to argue with the science, people.



I’m thinking of challenging the hypothetical spirits of my ancient human ancestors. What fast should I try!?


You have several options to choose from. Think of it as a menu, except when you order you won’t get any food. 😞 Am I mean? Maybe a little. 😉 Haha 😂

6 Most Popular Intermittent Fasting Protocols

There are the main fasting protocols you can try.


Lean Gains Method

Popularized by Martin Berkhan, this is one of the most straightforward (and easiest to follow) methods out there. It basically states that you should fast 16 hours each day (if you’re a man) and 14-15 hours (if you’re a woman). So, if you’re following the math this means that you will have 8 hours to eat. This is called your feeding window. Sound simple? It is! How about a handy chart to make it even more simple (cross that) simpler. Ok, here you go!

P.S. It’s very important that you don’t over-indulge when you are in your feeding window. You still want a calorie deficit to guarantee you are going to lose weight. So hold off the chocolate chip cookies and pancakes for your cheat meal, ok?

24 Hour Fast

Brad Pilon popularized this method with his book, “Eat. Stop. Eat.”

It suggests you do one or two 24 hour fasts per week. This is a little more challenging than the 16/8 protocol but trust me – it CAN be done. When I do these, I usually fast from dinner to dinner. This means that if your last meal was supper on Monday night, you wouldn’t eat again until supper on Tuesday. I usually like my fasts to be dinner to dinner since I find it extremely challenging to sleep on an empty stomach. Below, you will find a possible application of this protocol with a Monday fast.

P.S.: Some fasts can go longer. I’ve tried 36-hour fasts and felt fine. For even longer fasts, you should request medical supervision.

P.S.2. : Research conducted by Dr. Satchin Panda suggests that due to the body’s natural circadian rhythm you should aim to start your fast as close to sunset as possible. You can check it out here.


Alternate Day Fasting

Ok. This one is pretty extreme and not for the faint of heart. To follow its protocol, you must alternate between 24-hour fasts and regular eating periods. This means that you’ll be fasting every other day. This is not recommended for beginners since if you follow it, you’ll significantly reduce your caloric ingestion, which could cause a series of health problems.

Note: There is a version of this diet that allows for 500 calories on the “fasting” days. Kinda (scratch that- definitely) defeats the point of fasting – if you ask me.

The 5/2 Diet

This fasting protocol – also referred to as the Fast Diet –  is accredited to Michael Mosley. Its premise is that you eat normally for 5 days of the week and reduce your calories for 2 days. Remember – when I say eat normally I mean – eat healthy. Unfortunately – It doesn’t mean you can eat all you want, pal!

Women should limit their total calorie consumption to 500 calories. While men should limit their caloric intake to 600 calories. Technically, as its fasting brethren above, it isn’t really a fast – since you ARE eating. Nevertheless, it should make you lose weight (and keep it off). And that’s what we want, right?

The Warrior Diet

This is often considered one of the first intermittent fasting protocols to gain some traction, going way back to the early 90s. It suggests that you eat only 1 calorie dense meal at night (within a 4-hour feeding window). According to this protocol, it’s important to eat only natural foods such as fruits, vegetables and grains. Think Paleo. Not Oreo.  None of those processed carbs you (scratch that – we) love are allowed! Sorry!

The main theory behind this diet is that it matches what our ancestors ate (both in terms of what and when). I.e. They didn’t have pop tarts back then. And they probably only ate when the hunters returned from a successful hunt: most likely at night.

Skip a few meals

This is for when you just want to sprinkle some fasts here and there. How? Well, you just skip a few meals throughout the week. Remember: every time you skip a meal you ARE consuming less calories than usual unless you overeat later on. This is a great strategy to get started but I’d rather take a more structured approach. It makes starting (and hanging in there) so much easier.


Still with me, pal?  Good for you! It’ll be worth it – but I won’t lie my friend. You face a hard road in front of you. At least – in the beginning. But hang in there, buddy! I got your back.


Here are the  7 toughest challenges of Fasting (and how to overcome them)


1- Intense Hunger Pangs

Everybody has this concern before fasting. Including me. We’ve all been hungry. We’ve all heard (and felt) our stomachs complain. We’ve all hoped for a closer lunchtime. Well – I won’t lie. The hunger can get excruciatingly tough at times. However, I have two bits of information that can help you suffer through the pain.

First, you’ll feel that the hunger comes in waves. Eventually, you will get hungry (Duh). But, if you have enough self-discipline to ride it out – it goes away after a while. Check out the handy chart I created below.


Second, I found (and hopefully you will too) that the hunger intensity decreases after you’ve fasted for a while. In fact, after a while, you’ll feel no hunger at all. Or at least it will recede to bearable levels. Check out hunger chart #2 below, which illustrates hunger intensity.

Hopefully, with this information, you’ll be ready to beat the Hunger Games, which can, for some people, be scarier than the movie.  “And may the odds be ever in your favor.”


2- Peer pressure (from friends, family and co-workers)

What are you doing to yourself? Do you want to starve to death? These are two questions that will come in one form or another from your family, friends or work colleagues. Sure- they mean well- but do they know what they are talking about? Probably not! You can tell these well-intentioned distractors that you’ve already done some research on the topic (heck – you can forward them this post). You can also tell them that the longest recorded fast was 382 days. Oh –  If you’re wondering: No, he didn’t die. And yes – he was obese. But we are talking about 24 hours here, people! So… tell them you’ll be fine not eating for ONE day!

3- Breaking the habit of snacking

Since I can remember –  I’ve been told to eat every 2 or 3 hours, the theory being that this stimulates your metabolism. It’s true, it does. But it stimulates the metabolism just as much as eating all of your daily calories in one sitting. So, because of this 3 hour pseudo-science (scratch that, crap),  you’re probably used to always chewing on something – I know I was. And you’ll probably miss that in the beginning. But the benefits are well worth it!

4-  Keeping track of your fasts

Did I begin my fast at 7 or 8 pm? When I started fasting, this question would frequently pop up in my head (thanks for nothing, memory).  When you are almost a full day without eating, every minute counts. Trust me on this one. You’ll be pretty anxious to break your fast. This is why I dig the Zero App. 

5-  Becoming (slightly) more stressed

I’m not a stressed-out guy – in the pull your hair out and pound your fist on the table kind of way. However, I do feel a slightly higher stress level while on a fast. But that’s not necessarily a bad thing, cause I think it actually makes me more alert. If you feel that your irritation levels are higher and you are snapping for any small reason. Relax. Take a deep breath. If that doesn’t work,  watch puppy videos.

6-  Having (possible) headaches

I’ve never had headaches because of a fast, but some people have reported it. If you feel a slight headache, it could be because you’re dehydrated. Don;t forget to drink a lot of water! If every time you fast, you have strong migraines, quit fasting (at least for now) and consult a doctor.

7- I know a guy who skips breakfast. He’s really overweight. Will that happen to me?

This is a classic case of correlation and not cause and effect. Your friend, let’s call him Carl from Accounting. Carl’s diet probably consists of cheeseburgers and kitkats. I bet he doesn’t exercise at all, either. So it’s his lifestyle that is making him overweight, not skipping breakfast, okay?

Okay. You’ve told me about ALL the benefits. You’ve told me how to overcome the most common challenges. Honestly – it all sounds a lil’ too good to be true. There’s one last thing I’d like to know before I actually start fasting:

What do the Haters say!?

You gotta love the haters, man. They sure do keep us on our toes, huh?

Here are some of the things the fasting naysayers have to say:

Insufficient research on Humans

Some people claim that most of the studies that have been done so far on Intermittent Fasting have been done in rodents. Truth is – plenty of research has been conducted on the subject – both on adorable mice and humans.

Correlation vs. causation

Some critics point out that some of the research out there doesn’t prove that fasting directly causes the health benefits and simply are correlated. In other words, people who are fasting are also doing other things to make them healthier like: exercising, sleeping well and taking supplements.

There are thousands starving and you are denying yourself food? What an insensitive a$$h0l3!

The problem of starvation is certainly serious (and concerning). But, sorry. I just don’t see the correlation between my not eating affects and the problem of starvation in certain parts of the world. If you want to help them, please stop judging me and do something to HELP THEM. Something like donating food (or money) to those in need.

It can promote eating disorders.

It’s true. Fasting could have a negative psychologic effect on people who already are prone to eating disorders.  If you are already underweight and a little too conscious about what you eat, you should definitely talk to your physician, nutritionist or psychologist before undertaking any kind of fast. You should know that fasting is not about starving yourself but consciously timing your meals in order to improve your health. Please don’t use it as an excuse to do harm to yourself. 🙂

It’s just a fitness fad. Don’t waste your time.

I beg to differ, sir (or madam). As I’ve touched on before, fasting has been around (for medical and religious purposes) for thousands of years. Its adoption (and benefits) have passed the test of time. If it is a fad, it is most likely the longest fad ever. Hey, somebody call the Guinness Book of World Records. We have a winner here.

Should YOU try Intermittent Fasting?

If you are healthy and up for new experiments, I would definitely give it a try. It’s a simple, easy way to lose weight and as we’ve already seen, a lot of research has been done, suggesting it WILL help you lose weight as well as SEVERAL other health benefits, as well.  That being said – Intermittent Fasting is NOT for everyone.


You should NOT try Intermittent Fasting (without first consulting a doctor) if you:

  • have medical conditions such as diabetes, low/high blood pressure and problems with regulating sugar


  • are pregnant, trying to conceive or breastfeeding


  • are underweight


  • take medications


Thanks for reading so far. You da’ real MVP! Perhaps you have some questions? Well, here are a few of the most frequently asked questions (and corresponding answers)

FAQ – Frequently Asked Questions about Fasting and Intermittent Fasting

Will I lose my hard-earned muscle?

All diets can cause you to lose muscle. This is why it’s so important to watch your protein intake and take appropriate supplements to compliment your diet. Some people suggest you take BCAA while fasting to reduce possible muscle loss. Note: This study suggests that people lose less muscle while on Intermittent Fasts (24hour) as compared to regular daily caloric restriction.

Can I exercise while on a fast?

Absolutely! There are studies showing that low volume fasted cardio can even boost your weight loss efforts.

On a personal note – I’ve tried high-intensity interval training (H.I.I.T.) while fasting and did not have any problems, either.

That being said – if you feel sick or dizzy you should stop exercising and have a light meal. Listen to your body, bud. Always.

What can I eat or drink during a fast?

You can’t eat anything. Zilch. Nada.  But, most fasts allow for drinking water, coffee, tea and diet soda (not recommended for obvious reasons).

Will fasting cause my metabolism to slow down?

Uh – No! Actually, exactly the opposite, according to this study. And this one, too.

Further Reading

The Complete Guide to Fasting: Heal Your Body Through Intermittent, Alternate-Day, and Extended


This handy book thoroughly explains all the benefits of fasting and goes (in detail) over the main types of fasts out there.


The author, Dr. Chang has used fasting to improve the health of 1000s of patients, with great success.


As a bonus you’ll get the 7-Day Kick-Start Fasting Plan as well as some liquid “healing” recipes.


Buy it:  Paperback /  Kindle  /   Audiobook



The Warrior Diet: Switch on Your Biological Powerhouse For High Energy, Explosive Strength, and a Leaner, Harder Body


If the Warrior Diet we discussed above tickled your fancy, you should buy this book. Relying on both scientific and historical premises, the author explains the reasoning (and the actual techniques) to make your fasting journey a success.


You’ll also get recipes and other bonuses free of charge. Well, actually – they’re not technically free, since you paid for the book. But you get the point.


Buy it:  Paperback /  Kindle  /   Audiobook





The Fast Diet – The Original 5:2 Diet: Revisited and Updated


If you are interested in trying out the Fast Diet we discussed – this is the book for you, buddy! Dr. Michael Mosley and Mimi Spencer do a heck of a job explaining the method (and the science) behind their preferred fasting method.


Buy it:  Paperback / Hardcover /  Kindle  /   Audiobook








The Obesity Code: Unlocking the Secrets of Weight Loss


Another bestselling dynamite by Dr. Jason Fung. This is one is slightly more scientific (if you’re into that sorta thing). It goes into great detail on why so many people are obese and the keys to maintaining a healthy weight. Spoiler alert: Fasting is one of the most effective methods. DUH.


Buy it:  Paperback  /  Kindle  /   Audiobook







If you are serious about Intermittent Fasting or any other diet to lose weight, you should TaskTwins a try. Finding an accountability partner can greatly enhance your odds of crushing your weight loss goals.

Medical Disclaimer:

You should always check with your doctor before starting any kind of diet or fitness routine. Especially one that can be on the  extreme side – such as Fasting.