The Beginner’s Guide to Intermittent Fasting – 2017 Update

“…But Tony the Tiger tells us that breakfast is the most important meal of the day! Grrrrrreat!”

This rule has become so commonplace throughout the society as a whole – especially in the health and fitness industry – that it’s readily accepted as fact:

“Want to lose weight? Make sure you start off with a healthy breakfast, so you can get that metabolism firing first thing in the morning!  “Eat breakfast like a king, lunch like a prince, and dinner like a pauper.”

“Want to lose more weight? Make sure you eat six small meals throughout the day so your metabolism stays operating at maximum capacity all day long.”

There are even studies that show those that eat earlier in the day lose more weight than those who ate later in the day or skipped a meal.

So, eat breakfast to lose weight and obtain optimal health.  

Case closed…right?

Maybe Not. Maybe there’s way more to the story. As skeptics, we operate from first principles: what if there’s science and research that shows SKIPPING BREAKFAST (the horror! blasphemy!) for optimum efficiency, maximum muscle retention, and body fat loss?

After firmly being on “Team Breakfast” for 28 years of my life, I’ve skipped breakfast for the past 3.5 years and will most likely never go back!

I want to share with you a concept about skipping breakfast (and other meals), and how your health can benefit as a result.

Tony ain’t gonna be happy, but today we’re talking about intermittent fasting. Even Boy George is getting in on the Intermittent Fasting Action (and has read this article!):

This is a topic that is controversial (which is funny – you’re just skipping a meal) as it turns a LOT of conventional wisdom on its head. This is why this article is filled with more sources and citations than the normal Nerd Fitness article. Here we go. 

What is intermittent fasting?


Intermittent fasting is not a diet, but rather a dieting pattern.  

In simpler terms: it’s making a conscious decision to skip certain meals on purpose.

By fasting and then feasting on purpose, intermittent fasting generally means that you consume your calories during a specific window of the day, and choose not to eat food for a larger window of time.

There are a few different ways to take advantage of intermittent fasting:

  • Regularly eat during a specific time period only.  For example, only eating from noon-8 PM, essentially skipping breakfast.  Some people only eat in a 6-hour window, or even a 4-hour window. AKA “feasting” and “fasting” parts of your days.   
  • Skip two meals one day, taking a full 24-hours off from eating. For example, eating on a normal schedule (finishing dinner at 8PM) and then not eating again until 8PM the following day. So you would eat your normal 3 meals per day, and then occasionally pick a day to skip breakfast and lunch the next day.

Now, you might be thinking: “okay, so by skipping a meal, I just eat less than normally overall, and thus I will lose weight, right?”  

Well, that’s partly true.  

Yes, by cutting out an entire meal each day, you are on average consuming fewer calories per week – even if your two meals per day are slightly bigger than before (which is crucial for losing weight).  

However, as we already know that not all calories are created equal, the timing of meals can also influence how your body reacts.  

How does intermittent fasting work?


With intermittent fasting, your body operates differently when “feasting” compared to when “fasting”:

When you eat a meal, your body spends a few hours processing that food, burning what it can from what you just consumed.  Because it has all of this readily-available, easy to burn energy (thanks to the food you ate), your body will choose to use that as energy rather than the fat you have stored.  This is especially true if you just consumed carbohydrates/sugar, as your body prefers to burn sugar as energy before any other source.

During the “fasted state,” your body doesn’t have a recently consumed meal to use as energy, so it is more likely to pull from the fat stored in your body as its the only energy source readily available.

Burning fat = win.

The same goes for working out in a “fasted” state.  Without a ready supply of glucose and glycogen to pull from (which has been depleted over the course of your fasted state, and hasn’t yet been replenished with a pre-workout meal), your body is forced to adapt and pull from the only source of energy available to it: the fat stored in your cells.

Why does this work?  Our bodies react to energy consumption (eating food) with insulin production. In addition to this, the more sensitive your body is to insulin, the more likely you’ll be to use the food you consume efficiently, which can help lead to weight loss and muscle creation.

Along with that, your body is most sensitive to insulin following a period of fasting. 

Your glycogen (a starch stored in your muscles and liver that your body can burn as fuel when necessary) is depleted during sleep (and thus during fasting), and will be depleted even further during training, which can further increase insulin sensitivity.

This means that a meal immediately following your workout will be stored most efficiently: mostly as glycogen for muscle stores, burned as energy immediately to help with the recovery process, with minimal amounts stored as fat.

Compare this to a regular day (no intermittent fasting):  With insulin sensitivity at normal levels, the carbs and foods consumed will see full glycogen stores, enough glucose in the blood stream, and thus be more likely to get stored as fat.

Not only that, but growth hormone is increased during fasted states (both during sleep and after a period of fasting). Combine this  increased growth hormone secretion, the decrease in insulin production (and thus increase in insulin sensitivity), and you’re essentially priming your body for muscle growth and fat loss with intermittent fasting.

The less science-y version: Intermittent fasting can help teach your body to use the food it consumes more efficiently, and your body can learn to burn fat as fuel when you deprive it of new calories constantly.  For many different physiological reasons, fasting can help promote weight loss and muscle building when done properly.  

But why does every health book say “6 small meals?”

small plate

There are a few main reasons why diet books recommend six small meals:

1) When you eat a meal, your body does have to burn extra calories just to process that meal.  So, the theory is that if you eat all day long with small meals, your body is constantly burning extra calories and your metabolism is firing at optimal capacity, right? Well, that’s not true.  Whether you eat 2000 calories spread out throughout the day, or 2000 calories in a small window, your body will burn the same number of calories processing the food.  So, the whole “keep your metabolism firing at optimum capacity by always eating” sounds good in principle, but reality tells a different story.

2) When you eat smaller meals, you might be less likely to overeat during your regular meals.  I can definitely see some truth here, especially for people who struggle with portion control or don’t know how much food they should be eating.

However, once you educate yourself and take control of your eating, some might find that eating six times a day is very prohibitive and requires a lot of effort.  Along with that, because you’re eating six small meals, I’d argue that you probably never feel “full,” and you might be MORE likely to eat extra calories during each snack.

Although grounded in seemingly logical principles, the “six meals a day” doesn’t work for the reason you think it would (#1), and really only works for people who struggle with portion control (#2).

If we want to think back to the caveman days, we’d have been in serious trouble as a species if we had to eat every three hours.  Do you think Joe caveman pulled out his pocket sundial six times a day to consume his equally portioned meals in Tupperware containers?  Hell no!  He ate when he could, endured and dealt with long periods of NOT eating (no refrigeration or food storage) and his body adapted to still function optimally enough to still go out and catch new food.

A recent study (highlighted by the New York Times) has done a great job of challenging the “six-meals-a-day” technique for weight loss.  

Martin from LeanGains points out two important quotes from the study:

“…The premise underlying the present study was that increasing meal frequency would lead to better short-term appetite regulation and increased dietary compliance; furthermore, it was hypothesized that these predicted beneficial effects of increased meal frequency could have resulted from more favorable gut peptide profiles, potentially leading to greater weight loss. Under the conditions described in the present study, all three hypotheses were rejected.”

“…We had postulated that increasing meal frequency would enhance the compliance to the energy restricted diet thus leading to greater weight loss, an effect possibly mediated by increased fullness. The present results do not support this hypothesis.”

Remember, the type of food you eat matters. Meal frequency is not nearly as important as the quantity and quality of food consumed.  This study reached similar conclusions.

Why intermittent fasting?

IF fast plate

Because it can work for you. Although we know that not all calories are created equal, caloric restriction plays a central role in weight loss. When you fast (either for 16 hours per day, or 24 hours every few days), you are also making it easier to restrict your caloric intake over the course of the week. This will give your body a chance to lose weight as you’re simply just eating less calories than you were consuming before. Do this consistently, and it can lead to consistent weight loss and maintenance.

Because it simplifies your day. Rather than having to prepare, pack, eat, and time your meals every 2-3 hours, you simply skip a meal or two and only worry about eating food in your eating window. It’s one less decision you have to make every day.

It requires less time (and potentially money). Rather than having to prepare or purchase three to six meals a day, you only need to prepare two meals.  Instead of stopping what you’re doing six times a day to eat, you simply only have to stop to eat twice.  Rather than having to do the dishes six times, you only have to do them twice. Rather than having to purchase six meals a day, you only need to purchase two.

It promotes stronger insulin sensitivity and increased growth hormone secretion, two keys for weight loss and muscle gain.  This was already explained in the previous section with relevant sources, but intermittent fasting helps you create a double whammy for weight loss.

It can level up your brain, including positively counteracting conditions like Parkinson’s, Alzheimer’s, and dementia. As explained here in this TEDx talk by Mark Mattson, Professor at Johns Hopkins University and Chief of the Laboratory of Neurosciences at the National Institute on Aging fasting is grounded in serious research and more studies are coming out showing the benefits:

Dr. Rhonda Patrick discusses intermittent fasting protocols here on Tim Ferriss’s Podcast, and Dom Diagostino discusses the importance of fasting here in potentially preventing/mitigating the onset of neurodegenerative diseases

Plus, Wolverine does it.

What are the drawbacks with intermittent fasting?


In my own experimentation over the past three years, I have found very few negative side effects with Intermittent fasting. 

The biggest concern most people have is that Intermittent Fasting will lead to lower energy, focus, and the “holy crap I am hungry” feeling during the fasting period and ruin them. People are concerned that they will spend all morning being miserable because they haven’t consumed any food, and thus will be miserable at work and ineffective at whatever task it is they are working on.

The following are my thoughts and experiences, and your results may vary:

Yes, the initial transition from EATING ALL THE TIME, to intermittent fasting MIGHT be a bit of a jolt to your system; it was for me. However, once I got through the transition after a few days, my body quickly adapted and learned to function just as well only eating a few times a day.

Although I fast for 16 hours per day, the following might help assuage your fears that skipping breakfast will cause your body to eat itself and your brain to implode:

This study explains that in participants after 48-hours of fasting, “cognitive performance, activity, sleep, and mood are not adversely affected in healthy humans by two days of calorie-deprivation.”

“So why do I feel grouchy when I’m not eating breakfast?” In this nerd’s humble opinion, a good portion of the grumpiness is a result of our eating habits. If you eat every three hours normally, your body will start to get hungry every three hours as it learns and becomes used to expecting (and receiving) food every three hours. If you eat breakfast every morning, your body is expecting to wake up and eat food.

Once you retrain your body to NOT expect food all day every day (or first thing in the morning), these side-effects become less of an issue (thanks to a substance our bodies produce called Ghrelin). However, you can expect a few rough mornings and maybe decreased focus at work because all you can think about is the breakfast you’re depriving yourself of. I found this to go away after a few days.

It’s important to understand that Intermittent Fasting is NOT a panacea. Don’t delude yourself into thinking that if you skip breakfast and then eat 4,000 calories of candybars for lunch and dinner that you will lose weight.

If you have an addictive relationship with food and you struggle with portion control, track your calorie intake in your meals to make sure you’re not overeating. If you skip breakfast, you might be so hungry from this that you OVEREAT for lunch and this can lead to weight gain. Again, the important thing here is that with intermittent fasting you’re eating fewer calories than normal because you’re skipping a meal every day.

Think about it in caveman terms again.  We certainly found ways to survive during periods of feast and famine, and that remains true today. imagine if you needed to eat in order to be active: what would hungry cavemen do? They would go find food, and that probably required a ton of effort. It actually takes our bodies about 84 hours of fasting before our glucose levels are adversely affected.  As we’re talking about small fasts (16-24 hour periods), this doesn’t concern us.

AN IMPORTANT CAVEAT: Intermittent Fasting can be more complex for people who have issues with blood sugar regulation, suffer from hypoglycemia, have diabetes, etc. If you fit into this category, check with your doctor or dietitian before adjusting your eating schedule.

I believe more research needs to be done for these particular cases and thus would recommend you do what works best for YOU.

Can I build muscle and gain weight while intermittent fasting?

muscle hypertrophy


In fact, I have been intermittent fasting for the past three years while building muscle and decreasing my body fat percentage.

I still eat roughly the same number of calories I was consuming before, but instead of eating all damn day long, I condense all of my calorie consumption into an eight hour window.

  • 11 AM Work out with heavy strength training in a fasted state.
  • 12 PM Immediately consume 1/2 of my calories for the day (a regular whole-food meal, followed by a calorie-dense homemade shake.)
  • 7 PM Consume the second portion of my calories for the day in a big dinner.
  • 8 PM – 12 PM the next day: Fast for 16 hours.

In a different method, my friend Nate Green packed on a crazy amount of muscle while fasting for a full 24 hours on Sundays.  

I’m not kidding when I say this has revolutionized how I look at muscle building and fat loss.  Ultimately, this method flies in the face of the typical “bulk and cut” techniques of overeating to build muscle (along with adding a lot of fat) before cutting calories to lose fat (along with some muscle) and settling down at a higher weight.

I prefer this method to the bulk-and-cut technique for a few reasons:

  • There’s far less of a crazy swing. If you are putting on 30 pounds and then cutting 25 to gain 5 lbs of muscle, your body is going through drastic swings of body mass. Your clothes will fit differently, you’ll have different levels of definition, and your body will wonder what the hell is going on.
  • You’re consuming less food and thus spending less money. Rather than overeating to put on 1 pound of muscle and 4 pounds of fat in a week or two, you’re aiming to eat exactly enough to put on 1 pound of muscle without adding much fat on top of it.  Yeah, it’s a delicate balance, but there’s far less swing involved. You are just slowly, steadily, and consistently building muscle and strength over many months.
  • There’s never a need to get “vacation-ready”: we all want to look good naked, right?  When you are just adding muscle, you don’t need to worry about getting your body ready before by drastically altering your diet (going on a miserable crash diet for a month). I like Anthony Mychal’s technique of never being more than two weeks away.  Keep your body fat percentage low, build strength and muscle, and if you happen to notice your body fat creeping up, cut back on the carbs. Within two weeks you should be back at your preferred body fat percentage and can continue the muscle building process.

Does intermittent fasting have different effects on men and women?

boy girl

Yes, intermittent fasting can affect men and women differently.

This article over on Paleo For Women goes extensively into the potential negative effects of intermittent fasting for women.

This PubMed study digs into women and intermittent fasting as well.

This article on Mark’s Daily Apple does a fantastic job of breaking down the differences between men and women too and how they are affected by intermittent fasting, ultimately explaining:

  • “One study, which I’ve cited before as evidence of a benefit to fasting, found that while IF improved insulin sensitivity in male subjects, female subjects saw no such improvement. In fact, the glucose tolerance of fasting women actually worsened. Ouch.
  • Another study examined the effect of alternate day fasting on blood lipids. Women’s HDL improved and their triglycerides remained stable; men’s HDL remained stable and their triglycerides decreased. Favorable, albeit sex-specific results.
  • Later, both obese men and women dropped body fat, body weight, blood pressure, total cholesterol, LDL cholesterol, and triglyercides on a fasting regimen. These people were obese, however, and perimenopausal women were excluded from the study, so the results may not apply to leaner people or women of reproductive age.”

Long story short: Yes, men and women will have different experiences with intermittent fasting; we’re all unique snowflakes (yep, especially you), and your body will be affected by intermittent fasting differently than the person next to you.

My best advice?  If you’re curious, get blood work done, speak with your doctor and get a check-up. Give intermittent fasting a shot, track your results, and see how your body/blood work changes as a result of Intermittent Fasting and decide if it’s right for you.

I’ve anecdotally heard of hesitant doctors who prescribed to the “6-meals-a-day” philosophy be surprised when a patient returns months later in better shape and with a better blood profile thanks to skipping meals.

Your milage may vary, so speak with a doctor or find a doctor versed in intermittent fasting protocols and treat it like an experiment on yourself!

Questions about intermittent fasting


“Won’t I get really hungry?”  

As explained above, this can be a result of the habits you have built for your body. If you are constantly eating or always eat the same time of day, your body can actually learn to prepare itself for food by beginning the process of insulin production and preparation for food.

After a brief adjustment period, your body can adapt to the fact that it’s only eating a few times a day. The more overweight you are, and the more often you eat, the more of an initial struggle this might be.

Remember, your body’s physical and cognitive abilities aren’t diminished as a result of fasting.

“Where will I get my energy for my workouts? Won’t I be exhausted and not be able to complete my workouts if fasting?” 

This was a major concern of mine as well.  And for my first workout or two, it was very weird to not eat before training. However, after a few sessions, I learned that my body could certainly function (and even thrive) during my training sessions despite not eating a pre-workout meal. Here I am a while back pulling 385 lbs. at 175 BW after a 16 hour fast:

A post shared by Steve Kamb (@stevekamb) on

As Mark’s Daily Apple states:

Fasted training can actually result in better metabolic adaptations (which mean better performance down the line), improved muscle protein synthesis, and a higher anabolic response to post-workout feeding (you’ll earn your meal and make more muscle out of it if you train on an empty stomach).

“I like the idea of fasted training, but I work a regular 9-5 and can’t train at 11AM. What am I supposed to do?”

Martin from LeanGains lays out a few different options for you, depending on your training schedule.  The best advice is to not freak out and overanalyze unless you are an elite athlete concerned with the absolute optimal performance at all time.

If you’re just a normal guy or gal looking to drop a few pounds and get stronger, do the best you can.

“Won’t fasting cause muscle loss?”  

Another big concern of mine, but it turns out…it was unfounded.  We’ve been told by the supplement industry that we need to consume 30 g of protein every few hours, as that’s the most amount of protein our body can process at a time.  Along with that, we’ve been told that if we don’t eat protein every few hours, our body’s muscle will start to break down to be burned as energy.

Again, NOT TRUE!  This study shows that our bodies are quite adept at preserving muscle even when fasting, and it turns out that protein absorption by our body can take place over many many many hours. Protein consumed in a shorter period of time has no difference on the body compared to protein spread throughout the day.    

“What about my body going into starvation mode from not eating?” 

Now, the thought process here is that when we don’t feed ourselves, our bodies assume calories aren’t available and thus choose to store more calories than burning them, eliminating the benefits of weight loss with fasting. Fortunately, this is NOT true.

As Martin from LeanGains so eloquently explains (as you can tell, he’s good at this stuff):

“The earliest evidence for lowered metabolic rate in response to fasting occurred after 60 hours (-8% in resting metabolic rate). Other studies show metabolic rate is not impacted until 72-96 hours have passed.

Seemingly paradoxical, metabolic rate is actually increased in short-term fasting. For some concrete numbers, studies have shown an increase of 3.6% – 10% after 36-48 hours (Mansell PI, et al, and Zauner C, et al).  Epinephrine and norepinephrine (adrenaline/noradrenaline) sharpens the mind and makes us want to move around. Desirable traits that encouraged us to seek for food, or for the hunter to kill his prey, increasing survival. At some point, after several days of no eating, this benefit would confer no benefit to survival and probably would have done more harm than good; instead, an adaptation that favored conservation of energy turned out to be advantageous.”

“This sounds crazy, I’m not gonna do it.”

That’s cool.  Are you losing body fat, building muscle, and getting a clean bill of health from your doctor?  If you can say yes to those things, AWESOME. Keep doing what you’re doing, because it’s working.   

However, if what you’re doing ISN’T working, or you’re not getting the results you were hoping for, why not give it a chance?  Hopefully the dozens of studies at least peak your curiosity.  Self-experimentation is the best way to determine WHAT methods work for you.

Tips and tricks about Fasting 

hungry ant

Don’t freak out.  Stop wondering: “can I fast 15 hours instead of 16?” or “what if I eat an apple during my fasted period, will that ruin everything?”  Relax. Your body is a complex piece of machinery and learns to adapt. Everything is not as cut and dry as you think.

If you want to eat breakfast one day but not another, that’s okay. If you are going for optimal aesthetic or athletic performance, I can see the need to be more rigid in your discipline, but otherwise…freaking chill out and don’t stress over minutiae! Don’t let perfect be the enemy of good.

Expect funny looks if you spend a lot of mornings with breakfast eaters.  A few weeks back I had a number of friends staying with me, and they were all completely dumbfounded when I told them I didn’t eat breakfast anymore.  I tried to explain it to them but received a bunch of blank stares. Breakfast has become so enGRAINed (zing!) in our culture that NOT eating it sounds crazy.  You will get weird looks from those around you…embrace it. I still go to brunch or sit with friends, I just drink black coffee and enjoy conversation.

Stay busy.  If you are just sitting around thinking about how hungry you are, you’ll be more likely to struggle with this. For that reason, I time my fasting periods for maximum efficiency and minimal discomfort:

  • My first few hours of fasting come after consuming a MONSTER meal, where the last thing I want to think about is eating.
  • When I’m sleeping: 8 of my 16 hours are occupied by sleeping.  Tough to feel hungry when I’m dreaming about becoming a Jedi.
  • When I’m busy: After waking up, 12 hours of my fasting is already done.  I spend three hours doing my best work (drinking green tea and listening to PM, which is exactly what I’m doing while writing this article!), and then comes my final hour of fasting: training.

I don’t have time to think about how hungry I am, because I keep my brain constantly occupied!

Zero-calorie beverages are okay.  I drink green tea in the morning for my caffeine kick while writing. If you want to drink water, black coffee, or tea during your fasted period, that’s okay.  Remember, don’t overthink it – keep things simple! Dr. Rhonda Patrick believes that a fast should stop at the first consumption of anything other than water, so experiment yourself and see how your body responds.

Track your results, listen to your body:  

Everybody will react to intermittent fasting differently; I can’t tell you how your body will react.  It’s up to you to listen to your body and see how making these adjustments change your body.

Don’t expect miracles.  Yes, intermittent fasting can potentially help you lose weight, increase insulin sensitivity and growth hormone secretion (all good things), but it is only ONE factor in hundreds that will determine your body composition and overall health.  Don’t expect to drop to 8% body fat and get ripped just by skipping breakfast. You need to focus on building healthy habits, eating better foods, and getting stronger.

This is just one tool that can contribute to your success…

To sum it all up


Intermittent fasting can potentially have some very positive benefits for somebody trying to lose weight or gain lean body mass.

Men and women will tend to have different results, just like each individual person will have different results.  The ONLY way to find out is with self-experimentation.

There are multiple ways to “do” intermittent fasting:

  • Fast and feast regularly: Fast for a certain number of hours, then consume all calories within a certain number of hours.
  • Eat normally, then fast 1-2x a week: Consume your normal meals every day, then pick one or two days a week where you fast for 24 hours.  Eat your last meal Sunday night, and then don’t eat again until dinner the following day.
  • Fast occasionally: probably the easiest method for the person who wants to do the least amount of work.  Simply skip a meal whenever it’s convenient. On the road? Skip breakfast.  Busy day at work? Skip lunch.  Eat poorly all day Saturday?  Make your first meal of the day dinner on Sunday.

Remember: One of the Rules of the Rebellion is to QUESTION EVERYTHING.  If this seems like something you’d like to try, give it a shot. If it sounds crazy to you, ask yourself why you think it sounds crazy, and do your own research and experimentation before condoning/condemning it.

I’d love to hear from you:

  • What are your questions with intermittent fasting?  
  • What are your concerns?
  • Have you tried intermittent fasting?
  • Have you had success with it, either with muscle gain or weight loss?

Thanks for leaving your comment, I’m excited to get the conversation started.


PS: We’re fans of Intermittent Fasting, which is why its part of the Nerd Fitness Academy, our online training course that is helping over 40,000 superheroes-in-training get fit, healthy, and happy.  Come on and join us!

PPS: Added an important caveat: If you are somebody who has blood sugar regulation issues (diabetes, hypoglycemia, etc.), discuss with your doctor or medical professional before making changes to your diet, even sharing this article and the cited studies with them. Remember, question everything!


Photo Source: seal mouth, tony the tiger, anatomy, cog, small plates, apples, fridge, ant, boy girl, kiwi

Get The Rebel Starter Kit

Enter your email and we’ll send it right over.

  • The 15 mistakes you don’t want to make.
  • The most effective diet and why it works.
  • Complete your first workout today, no gym required.
  • These are the tools you need to start your quest.
  • trez03trois

    Hi! I’m working night shifts and don’t get to sleep 8 hours straight during the day. I was planning on doing 12/12 intermittent fasting. Can you suggest tips on how to schedule IF? I workout at night before working. Should I drink my protein shake before working out (before my fasting period starts)? does the effectiveness (weight loss benefits) depend on how long you are fasting? Thanks 🙂

  • Carrie Sanders

    Is it okay to workout before eating the last meal, verses your schedule of working out before your first meal?

  • Shyam Shukla

    What worked for me was this amazing guide.
    Tell the right methods of doing IF and helps in staying healthy.

  • PetiteD

    Can different methods of IF be combined? I was thinking of doing the regular 16:8 daily and then fasting for 24 hours once or twice a week. I’m a woman entering my 30s. I’ve been thin all my life until recent years, so I’m trying to get my body back to a good BMI (I’m currently overweight and would need to drop 25+ lbs to get to a healthy weight), ideally before having children. I started off doing IF a few weeks ago on the 16:8 method (more like 15:9, but I’m working up to 16:8). I’m starting to see results, slowly but surely, but tried fasting for a day and saw a marked improvement. Just wanted to make sure that combining both methods is safe before continuing long-term. Thanks for this great article. I wish I found it before I started gaining so much weight.

  • L G

    I just finished reading The Secret Life of Fat and I am all on board with the fasting the author recommends for women (16 hours at a time) but I don’t want to give up my morning coffee with a splash of soy milk which also contains sugar (Starbucks). If I drink a few tablespoons of soy milk during the 16 hour fast, am I totally ruining the fast? Second question, what if I use an artificial sweetener like stevia or monkfruit? Does that ruin the fast? Thank you!

  • PrairiePixie

    I’ve lost 10-15 lbs since July skipping breakfast and eating more healthy choices and portions for dinner. It’s terrible but I’m still struggling with the midnight careless uninhibited walks to the fridge. Deadbolt?

  • JaimeZuub

    That’s awesome Samantha! Intermittent fasting has been absolute game-changer for weight loss. I think it’s just starting to become more mainstream and people are beginning to realise just how effective it is.

    If you want to see crazy fat loss results, do some exercise in the last few hours of your fasting period. In a fasted state you have a greater ability to target the stubborn fat stores on your body. There’s a really effective 21 minute workout by Adam Steer that you can do at home without any equipment. Here it is: Adam Steer’s 21 Minute Method

    I feel sorry for people who are doing their low carb diets when you can eat tasty food every day and still lose weight! 🙂

  • jeremy martinez

    I train at 5am in the morning in a fasted state. Am I suppose to consume any protein directly after i work out? I break my fast at 1130am and stop my eating window at 630-7 pm

  • Shyam Shukla

    What worked for me was this amazing guide.
    Tell the right methods of doing IF and helps in staying healthy.

  • Ravi Kumar

    What worked for me was this amazing guide on Intermittent Fasting.
    Tells the right methods of doing IF and helps in staying healthy.

  • Shannon

    I really want to try this, but I have some medical conditions that require me to take meds every eight hours and if I take them on an empty stomach they make me sick (on top of the fact that my Dr says NOT to take them on an empty stomach as it could cause ulcers). Anybody got any help for this?

  • nick

    You cant put a price on optimal mental and physical health. 16:8 is the best IF ratio for men (14:10 for women)

  • Mar Sánchez

    Hello, thank you so much for the article. I would like advice!I am 19, my height is 156 cm. I weigh 65 kg and would love to lose 15kg in the next 5 months. Will IF help me get better results if I follow a diet of 1000 calories a day? I would need to have two meals of 500 calories each during my window or would it be better to eat the 1000 cal in juat one meal??

  • Johnny Bravo

    Just answer the FUCKING QUESTION. Everyome is a dam expert on IF but needs to give every piece of knowledge they’ve ever come by. What to eat or drink. No fuckin history, Not your mistakes and tribulations. Food & Drink. FUCK. These people are almost worse then Trump haters. Thanks for nothing.

  • Johnny Bravo

    Are you still with that trainehe’dause he’s a douche.

  • Johnny Bravo

    What your sayimg is BS. The body will burn fat as it needs. Your still stuck with old dieting ideas with their heads up their asses. That would be like saying don’t burn too much gas in your push it half the week. With intermittent fasting the body will work as it should. If very fat you won’t even have excess skin. PS you’ll never burn muscle on IF.

  • Johnny Bravo

    The person who wrote this must be new to IF. IF is not new. It’s need used by bodybuilders for more then 30 years. Please learn more before giving advice. Please write me with any questions if you want the truth. Your probably not ready for it but I’ll tell you anyway

  • Michael Cripe

    Love this info.

    So it really doesnt matter what 8 hours I fast.?? I started today and worked out at 4am and ate from 4-noon and now fasting from noon until 4am,

  • The Random VibeZ
  • Lucy Funaki

    What if i work out in the evening? So around 7pm is when i am able to work out. Would a 1pm – 9pm window workout? And would eating a big dinner after training still help with weight loss?

  • Ravi Kumar

    Thanks. This is very useful indeed.

  • Dominick Acevedo

    i sleep late and wake up late but i don’t eat anything after the big dinner at 7 and i usually wake up around 1 or 2pm when i start to eat after fasting. Does my sleep schedule effect my fasting?

  • Gurkis

    Whaddup, great article!


    Swedish male, 28y, engineer, abour 18-22% BF

    A year ago I started only eating lunch. Like every day. I dont know why, I just felt like i was getting fat and had to make a change.
    I didnt do any research or check anything out. I only went with instinct. It really just felt right with the simple explanation:

    If you stop eating you wont get fat (so obvious btw).

    So here I am one year later, no idea of how many kilos i’ve lost (dont really care) but everyone I know says Im getting too skinny..

    People worrying about getting hungry:

    Fuck yeah, first week or so.. get through that and phuufff (sound effect): You will actually learn to only get hungry close to lunch, for realZ. in addition to:
    losing weight just from nowhere. and btw: I have not worked out for real in like 2 years. once a month maybe, the rest of the time I work in an office and have zero sport interests. I play computer games like all nights..

    I wasnt that surprised this method worked and is used by like nerdy gym-Bobs. That is because it really feels like a natural choice. After two weeks it felt way more natural to skip both breakfast and dinner then any meal felt before. And yeah I have saved money like crazy too. Probably more than 50% of food budget saved and I eat out almost every day.

    Btw; If you wanna save money you CAN try this, if youre fat you SHOULD try this, if youre BOTH FAT AND POOR this “diet” is too fucking obvious. the end.


    Dont start working out while following my steps, it will hurt your wallet and you get fat again. fat with muscles


  • exstock

    As a female, I wish you’d given the “doesn’t work the same for females” disclaimer right off the bat. Even reading carefully, I almost missed it, and it’s a big deal!

    It was also very disappointing to read the whole thing, get sold on the idea, and then read the linked article explaining why I shouldn’t do it.

  • Ken Layton

    Like the article but I’m new to this and not sure what my meals should consist of.

  • Alejandra / SimplyCrudelicious

    Great post! I’ve started intermittent fasting over a year ago without even realizing it, now ready to pay more conscious attention and intention to it and see how it goes for me! 🙂 Thanks

  • Patricia Burnett

    I have no thyroid and while that is not the reason for my putting on weight it makes it very difficult to loose. Will fasting help me?

  • Cott

    After a long daunting research and plenty of contradictory/confusing opinions while trying to understand what sort of IF may work best for me, a few weeks ago I happened to come across a site which seemed to be pretty straight forward regarding different types of IF programs acording to what the end goal may be. I have done an initial trial of 16:8 during 5 consecutive days and already noticed great skin improvements and weight loss!! Really looking forward to making a more permanent habit out of it now. Their 4 week coaching program sounds promising, I would have definitely benefited from some support through my initial days last week. Hope you find it helpful:

  • Colleen

    This was really helpful; I’ve been incorporating IF into my routine and typically go for 18 hour cycles with off days, because I don’t want to impact my metabolism (one effect that I’ve noticed when I go longer than 20 hours…). I’ve also learned a few other tricks that work well for women, particularly on controlling hunger / appetite while first getting started. (Posted about it here: )

  • Laurie Hendy

    Awesome article! Best explanation I’ve seen on the net so far!

    1 question from me…I train at 6am but would prefer my fast to be from 8pm to midday. Should I still have a post workout shake or meal? Or is it still best to push through to midday?


  • Shyam Shukla

    What worked for me was this amazing guide on IF.
    Tells the right techniques of IF and helps in staying healthy.

  • Smiff Brian

    I’m a early bird and usually done with the gym by 7am. Should I continue to fast until noon? Also, would aminos be ok to sip on during the fasting period in the morning because of the workout?

  • jagjit bhatia

    INCREDIBLE ARTICLE! Thank you so much for writing this, it’s extremely helpful. I was looking for an article like this everywhere but I couldn’t find a good one. Thanks again and keep producing awesome content!

  • king ibra

    does 8/16 methot must be everyday? or can we get benefit if we do it for 2-3 days in a week

  • John Caluda

    My training and work schedule make it impossible for me to train after my fast period. It is exactly the reverse. My training takes place at 6pm 5 days a week. It’s a group thing so I can’t change it. I eat my last big meal or protein shake and don’t eat till noon the next day. How does this effect my calorie burn, and mussel gain by working out in the middle of the feasting period.

  • Koraima Chavez

    Hi. So i would love to intermittent fast but i go into work at 3am i get home at 9am and i eat then i sleep until 12pm or 1pm then i eat at 4pm for my last meal. So how should go about planning my intermittent fasting ?

  • Toni Durchin Werner

    Right now I’m eating at 12pm and 7pm. I’m unclear as to how long and how much I should be eating. This is my first week of IF and so far it has not been hard.

  • Andrew

    right now i am trying an extreme way, i eat on monday at 1 pm, and then the next time i eat is wednesday 3 pm, basically i am not eating for 48 hours.. but i don’t feel i am losing weight. is it because when i am eating on wednesday i ate too much? but i only eat once every 48 hours…

  • Amanda

    Great article! Do you have any recommendations for your pre-fasting 8pm dinner (if 10am training session during fast) and post fasting noon meal (after training)?

  • The Foxy Dad

    Still one of the best articles on IF I’ve come across.

  • Deepak Sharma

    Hopefully Quick Q: I am not able to workout at 11. Is it ok for me to start my fast at 3pm and break it at 9am in the morning. Pretty much stop eating dinner instead of breakfast?

  • MissSsiNim

    I’m looking in to intermittent fasting and after reading a lot of Jason Fung’s work, this article’s emphasis on calorie restriction is a bit disconcerting. There is some amount of calorie reduction with IF, but calories in calories out is a faulty premise to begin with

  • Paula Buchanan

    I have been doing IF for about 3 months. I have lost about 25 lbs so far and I am a 51 year old woman who has not gone through menopause yet. I also have adrenal issues, so possible blood sugar issues, but I don’t really feel I am having any problem with the IF. I fast for 24 hours twice a week. I do bodyweight workouts 3 days a week and the other days I do milder exercises trying to heal my back, and I walk at least 3 days a week, but as weather gets better, that will go to 6-7 days a week.

  • Sabina Sasnouskaya

    Thank you for the article! It did work for me as well! I ate only between 12pm to 2pm (just a meal any time between 12pm and 2pm plus some sweets even), in 4 weeks lost 7 kg and am not feeling deprived as I allow myself sweets 🙂

  • Jerry Gill

    Question. I only want to burn about 10 lbs. I’m 151 and I feel and cycle much better at 142. How many times per week do you suggest fasting. I often skip breakfast anyway. I think the 16 hour fast would work best. Plus if I have time in the morning I enjoy a fasted 30 minute bike ride. I often don’t have time to eat a lot at work anyways. 2-3 x per week sound good?

  • naloredo

    I think I am going to try this but have breakfast at 7:30am. Lunch between 12pm-1pm and then dinner at 3:30pm
    I will fast between 4pm-7am.

  • Lisa

    Hi there. Can you fast every day? If you do this over a long period of time, will it become ineffective at all? If your body get used to your new routine?

  • Arra Remedy Merrill

    Is it going to affect my weight loss if I consume splenda and other zero calorie sweeteners in tea?

  • Sportrocgirl55

    What foods do you eat on your IF? Is this a Ketone diet?

  • cheryelle crane

    What foods do you eat between the IF? Is there a list of what to eat and what not to eat? I’d like to try this, nothing else has worked out for me.