Intermittent Fasting FAQ: Top 5 Questions about IF

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Notes on the Basics, Timing, and Breaking a Fast

Intermittent Fasting FAQ

Just a quick one for you today. Given how prominently Intermittent Fasting is featured in my programs, and how often I discuss various Intermittent Fasting protocols it’s not surprising that I get a lot of questions about the practice. What’s okay? What isn’t? It’s even less surprising that the same questions get asked over and over and over again. This means, of course, that I should write a post to address these questions.

Certainly, it will help a lot of people, but my more self-serving reasons is that it would be much easier, in the future, to just send a link to this article, rather than continuing to type out the answers over and over, several times per week.

Why did it take me so long to do this? Because I’m a big, dumb animal, folks.

Me, basically.

Anyway, if you’ve read a lot about fasting, you’ll probably know the answers to a few of these. If you’ve recently begun fasting, then you’ve probably asked yourself (or me) one of these questions, or at least been curious. Definitely check these out.

If you’re a complete neophyte to the idea of fasting, you’ll get a lot out of this article, but you really should check out the basics first. My articles Intermittent Fasting 101 & Intermittent Fasting 201 should be enough to get you started.

Finally, I just want to reiterate that this is intended to be a quick blog to save us all time, not a dissertation, or even a full article. As such, it’s not filled with science and links to PubMed.

Meaning that you might be disappointed if your general reaction to is this:


Don’t be that guy.


With all of that said, on to the questions.

On General Fasting

1) Fasting for 16/24/36 Hours Seems Hard; Like, Weawwy Hard–Will I Die?

Yes, you will die. But probably not as a result of fasting.

And, honestly, it’s not that hard once you get used to it, so just man up. I don’t mean to make light of it–your first foray into fasting can certainly bring with it a certain degree of discomfort. You’ll be a little hungry. This is normal, and it’s nothing to worry about. And, the longer your fast (as in, practice the habit of fasting, not maintain one single fast), you’ll find that you don’t get as hungry as often. And so fasting becomes much easier.

The abbreviated version of why this happens: there’s a hormone called ghrelin that controls hunger; the production of ghrelin is dependent on when you eat. (So, producing ghrelin makes you want to eat, and eating produces ghrelin…which makes you want to eat more. More than a little annoying.) Ghrelin secretion in your body happens on a schedule based on your eating schedule; meaning the more often you eat, the more often you produce ghrelin, and the more often you want to eat.

All of which explains why you’re always hungry. Fasting will be hard in the beginning, because you’ve conditioned your body to produce ghrelin on a schedule, and so you have to push through that hunger.  Here’s the good news: ghrelin secretion begins to adapt to new eating patterns pretty quickly. Fasting helps you influence this because you’re eating less often, which means you’ll get hungry less often.

Science lesson over. The upshot is that the discomfort from fasting fades quickly, and the benefits (both longterm and short term) outweigh the acute inconvenience.

Or, as I said earlier, man up.

2) But Wait! Isn’t It Bad 4 My Metabolismzz?

No, it isn’t. This a myth that I could write about all day, so, again, a summary.  The idea that not eating will slow your metabolic rate is based of the fact the eating increases your metabolic rate; the increase occurs when you eat due to something called the Thermic Effect of Feeding (TEF). Basically, you expend energy to break digest, absorb, and utilize the food you eat. This part is true.

Here’s the part that’s not true: the suggestion more often you eat, the more often your metabolism will increase, therefore not eating often can lead to metabolic slowdown. For years, you’ve been told that eating 5-6 small meals per day helps you keep your metabolism elevated. Again, not true.

The fact is that TEF is determined by your total energy intake, not how often you eat. So, it doesn’t matter if you have 2 meals or 8, as long as you’re getting the same number of calories, the effect will be the same.

All of which is to say that a daily fast of, let’s say 16 hours, does not decrease your metabolism.

On Timing

These questions comes up a lot with people who practice 16/8 fasting. In a perfect world, that model looks like this: fast for 16 hours, hit the gym, start eating. The suggested feeding window is 2-10pm; so, ideally, you train at 1pm. That’s a problem for a lot of people who have pesky things called “jobs.”

But, simply because you can’t follow that one specific recommendation doesn’t mean you can’t utilize fasting, or get great results from it. To that end, here are the two most common schedule concerns that I get, and my recommendations.

3) I can only train in the evening, after work. Should I wait until then to break my fast? 

Depends. You can wait to break your fast if the following apply to you:

  • You don’t mind eating your first meal at 6 or 7pm.
  • Your workout won’t suffer from the extended fast.
  • You won’t have an issue getting in all of your calories and macros before bed.

If those things are not an issue for you, sure, you can wait to have your first meal until after your workout. But, you don’t have to. The second option is to simply break your fast at around 1pm with a moderately sized protein rich meal, have a shake or something like it a bit later than one (up to you–if I eat before my workout I puke), and then have some BCAAs before training at about 5:30pm.  When you finish your workout, start eating the rest of your calories.

I’ll mention that option one is probably better suited to fat loss, while option two is better for muscle gain.

4) I can only train in the morning, before work. Should I eat after? How do I handle this? 

The obvious question here is about meal timing: if this person finished their workout at, say, 7am, they have to make a choice and either:

  • break the fast post workout, and then have an eating window of 8am-4pm. This can work, but you’re missing out on all of the nifty hormonal stuff that comes with not eating in the morning, including increased growth hormone secretion and better insulin management.
  • don’t break the fast post workout; simply continue fasting until 1-2pm. Much easier in terms of thinking. Probably better and more effective from a hormonal standpoint. But carries with it the inevitable question about wasting the post workout window. It’s a tradeoff – can’t have everything. You could also take BCAAs post workout to get some PWO anabolizmz. (More on BCAAs below).

On Breaking The Fast

5) Will XYZ Break My Fast?

I get this one a lot. People want to know what constitutes breaking a fast, and what, if any, caloric intake is acceptable.

Here’s a list of things to DO NOT break your fast:

Those things are pretty much fine in just about any quantity. Cool?

Here’s a list of grey area stuff, with a note on why gets the official rating of sometimes.

NON-BLACK COFFEE – You can add all sorts of stuff to coffee to make it either more delicious or healthier–or sometimes both. But, adding anything to coffee that has calories can potentially break your fast. A little heavy cream makes things tasty. A little coconut oil gives you some medium chain triglycerides, and you know how delicious those are (see Bulletproof Coffee).  

If you have a single cup of coffee per day, this is a non-issue; but if you need 4-5 cups to get going in the morning, and you’re adding a tablespoon of cream or coconut oil to each on, that will add up. There’s no hard and fast rule, but I say just try to keep your total caloric intake below 100, even if it’s from fat. The poison, as they say, is in the dose.

 I don’t have a problem with diet soda or artificial sweeteners in fairly limited quantities. However, not all are created equal, and they can exert different effects. For example, one of the sweeteners in Coke Zero is acesulfame potassium, which has been shown to be (potentially) insulinogenic; so that’s not the best choice during a fast, because you want to minimize insulin. Diet Coke, on the other hand, doesn’t have it. 

Is it going to make a huge difference? Probably not. Is drinking diet soda going to kill you and make you fat and give you herpes? Probably not. Still, probably best not to make it your primary liquid of choice. Again, the poison is in the dose.

 Branched Chain Amino Acids are fantastic for a number of reasons, and when it comes to fasting, most people consider them necessary. BCAAs can blunt hunger, help you build muscle and retain LBM, and allow for better workouts over all. So, why are they in the grey? 

Very simply, they’re extremely insulinogenic. The production of insulin shuts down the production of growth hormone, so dosing with BCAAs may negate some of the benefits of fasting. Whether this is actually the case is open to debate. Many experts recommend this; for example I’ve heard that the position of BCAAs not breaking a fast referred to as Berkhan’s Law, named for Swedish nutritionist Martin Berkhan, one of the godfathers of the IF movement.

My personal position is this: if you’re focused on insulin management (for example, during an Insulin Reset, which appears in Phase I of Engineering the Alpha), I would skip the BCAAs until after your workout. If you have good insulin management or are trying to gain muscle, go for it.



I’m looking to keep this post dynamic and update it as time goes on, so feel free to drop any Q’s about fasting below, and I may steal feature them going forward.

Hopefully, this post will help you as much as I know it will help me–whether you learn from the information or just refer people to it so you don’t have to keep answering these!


Happy Fasting,


About the Author

John Romaniello is a level 70 orc wizard who spends his days lifting heavy shit and his nights fighting crime. When not doing that, he serves as the Chief Bro King of the Roman Empire and Executive Editor here on RFS. You can read his articles here, and rants on Facebook.

  • Ethan Rowan

    John, big question here… Amaretto Almond coffee contains 2 cal per serving, I am under the impression that black coffees doesn’t break your fast but I am concerned about this and any other flavored black coffee. I always drink my coffee black when fasting however should i be staying away from these flavored coffees? Do they have any hidden sweeteners that may harm my fast or break it? Id love to know your thoughts,

    Many thanks, Ethan

  • Siabatto Marco

    What about black tea? For example the one sold at Walmart already made for you but unsweetened, would that potentially break my fast?

  • Cody Trimmell

    This question relates somewhat to the timing concerns you addressed, but is not quite the same:

    As you noted, I, like many others, have been following the 16/8 fasting schedule. However, I have also read several places that one of the important factors of this is fasting for 4-6 hours upon waking (as part of the 16) to encourage fat burning/loss. My question is – if I sleep in/wake up late and my fasting window has already clocked or is getting close to the 16 hours off, should I still wait for 4-6 hours after waking to eat, or is it ok to go ahead and eat within like 2-3 hours of waking since I don’t want my 8 hour window to be later in the day/get off whack? Or, conversely, will that harm the cycle I’ve been working towards and encourage ghrelin production earlier after waking again? Thanks in advance for your response.

  • Jeremy May

    This may seem like a really stupid question, but I’m definitely new to If. Cough drops… Do they break the fast? Or is the poison in the dose? 1 – 3 fine 5+ break? How sensitive is this process?

  • Brian Siegel

    Can I combined 2 methods of IF? I have been doing 18/6 for a bit and feel great. Can I also fast for 24 hours 1 day per week too?

  • Жарко Милошевић

    Does egg whites break fasting ?

  • Louise Gadoury

    I’m super proud of you. I am a master googler and your views always win over others for many reasons. you seem to always be the final word. you’re doing a really great job. just sayin’.

  • Robert Vitztum

    Calorie deficits and goals.

    Obviously in order to lose weight people need to hit there calorie goals for the day but I haven’t really found an FAQ around whether or not hitting or missing this goals dramatically change results.

    The day to day miss is pretty standard but I have found it hard to hit my calories goals on a regular basis. This is simple I know, the answer is to eat but i had some questions you might be able to answer.

    I am attempting to lose weight and wouldn’t mind building muscle. From what I have found my dci needs to be 2250 with 225g in carbs and proteins and 50g or less of sugar. I am choosing to go the route of 8/16- seems easiest for me. I like the idea of IF but wasn’t sure if i come in too low on calories on a regular if the results will change. Coming in over i know isn’t as big of a deal but everyone i speak with always tells me the importance of eating enough calories for the day..

    The question. If I do not hit calories on a consistent basis will IF be useless?
    During the 8 Hours of feeding should i eat as much and as often as long as it fits my intake goals or should I only eat 2 times in this period?

  • Amir Gandhi

    Hi Roman

    Does water with lemon or apple cider vinegar break your fast?

  • Catherine Mc Keon

    Is it ok to fast everyday? Or should it just be evey other day? Say eat from 1-9 everyday or every second or third day. Thanks

  • Andrea

    Hi Roman. I am brand new to IF. Could you suggest a good book to read as I embark on this journey? I would like to know what foods and quantities are best to consume during nonfasting times.

  • Rose Parak

    Can i add an atificial sweetner to my black coffee? will this brake my fast?

  • Celia Kristi Gunawan

    Hi, I have a question, if half of lemon + water during the fasting period break the fast? Thanks!

  • Your link to Green Powder is broken.

  • Ashley

    I’m doing No grains no sugar combined with intermittent fasting.
    (Post work out evening meal window)
    relieved to hear that my morning green tea with cream is permissible!

    ‘Metabolismzz’ made me laugh

  • Morgan Schenk

    Im currently doing a 20/4 intermittent fasting diet. But I have some questionable items I am consuming throughout the day. Looking for clarification. Here are my items.

    2 tablespoons of apple cider vinegar, organic lemon, cayenne pepper(in water)

    Yerba Matte w/ organic cinnamon(2 cups)

    Diatomaceous earth(in water)

    Anyway am I sabotaging my fast? The only thing that holds any carbs is lemon.

  • Luiz Miranda Lmt

    Just wondering, why fasting have a unbeliable result in increasing the HGH hormon, I do understand it goes up, but why ? Also the intake of pure black coffe, can I have a few in the morning (while fasting ) ?

  • Maritza Lea

    This article is everythinggggggggggg. I love how it was written and you got RIGHT to the meat of the topics I was questioning. I just started IF so this was perfection. Thanks!! -Maritza Lea

  • Dani Parham

    Also just trying to keep this is simple as possible

  • Dani Parham

    If you are doing the 16/8 fasting, starting at 8pm to 12pm and then eating until 8pm, If you don’t exactly eat all the way up to 8pm does that break your fast. Also – I’m trying to include this and go to the gym 2 days a week and workout between 530-615. If I continue on with my day, not eating until 12pm, how does this affect me

  • Eddie Durdin

    What if I don’t want to take BCAAs after an 8AM workout and keep fasting until my normal window of 12-1pm breakfast? Won’t ghrelin and GH levels maintain my anti-catabolic state anyway? Won’t my insulin levels remain low anyway? Won’t my T AR upregulation remain positive?

  • Kyland Young

    Thank you for this awesome post! I have been trying IF for a couple of weeks, but my schedule has made it difficult some days – I typically sleep from 11:45-5(sometimes 5:15), monday-friday, and do my workout from 615-7. I like to take my whey protein right after workout. My difficulty has come from having to stop eating at 3-4pm every afternoon – and going to be after not eating since 3-4pm sometimes makes going to sleep uncomfortable because I’m trying to sleep on an empty stomach. Do you have any suggestions to make that late afternoon/evening hunger more bearable?


    id love to have a bit of info on knowing when to break your fast , signals from the body etc.

  • jessketo42

    If I drink BPC 12 hours into my 16 hour fast – will my body burn the fat from the butter/MCT instead of my body’s stored fat?

  • James Bock

    What’s up, John? I just stumbled on this article, and I’m not sure if you see the comments anymore, but I’m wondering about Bulletproof Coffee. You suggest <100 calories of fat in coffee while fasting, but Dave recommends 1-2 tbs of both butter and MCT, claiming it won't break your fast. Any thoughts?

  • J Benedik

    Hi John, thanks for three very informative posts on this topic. Do you have any follow up reading I could do on how this process differs (if it does) for women?

  • Rachel Kenny

    Hey, will fish oils break the fast?

  • Carlos Menendez

    Roman, thank you for Engineering the Alpha it has change my life and body. I would love for my buddy to start the alpha training but he is a diabetic, How does IF affect Type 1 and type 2 diabetics?

  • Mojorisen X

    Hey Roman,
    Question(s): I have started the 16/8 fast and I am very new to this whole world of IF. I am exercising roughly 12pm and eat/break the fast by about 1pm. I do my eating portion until 9pm then start the fasting phase again at that time. Those are the time frames you suggested and they work for me. Here’s the catch. I work swing shift so my morning is 12pm when I start my work out. Is eating at 1pm not a good idea? Should I hold the fast longer? To make it simple, from the time I wake up to the time I exercise and to the time I break the fast, how much time should pass, 6 – 7hrs?
    I saw in the post in FAQ’s of the person who asked about working out in the morning and eating after, you said it may not be as successful because if missing out on the hormonal stuff. In essence I am in the same boat since I wake up and excercise. What is more important, the fasting in general or the fasting while awake? If I am fasting from 9pm to 1pm the next day is that ok? I am ending my 16 hour fast with a workout and a meal.
    Also, When I get home from work, about 3am, I am hungry sometimes, I cant have coffee or green tea, would Almonds break the fast or some other nut if I had that? Or Chia seed in water or something like that?

  • Pharamcydropship

    Very nice blog. I liked the post.

  • Minh Chien Tran

    Hey Roman. I am currently on phase 2 of your program. Just wondering if drinking some energy drink pre-workout on the 24 hour fast consider breaking the fast?

  • Jose Wilches

    Hey there, quick question on topic, will L-tyrosine, 5 Htp or nootropics supplements break the fast?

  • Paul

    I fast 7pm-11am problem is my shifts have all changed in work which means I will not be able to drink protien etc after my workout which I estimate i will be finnished around 7am before my shifts changed i finnished a daily workout around 10:30 am so it was never a problem would this affect muscle growth if i waited say 4 hours after my workout to drink/eat protien?

  • Bruce Hill

    Hey Roman, Great post.

    I do a 36 hour fast about once a month. I’m also a huge fan of Bulletproof coffee. On my fast days, I have a cup of Bulletproof coffee at lunch with about a 1.5 tablespoons of grass fed butter + 1tsp of caprylic acid. That really smooths out the afternoon for both energy and hunger, but is that killing my fast? Thanks and keep up the good work.

  • Rouge Surreah

    Ive also read that putting grass fed butter or coconut oil in coffee prior to a fasted training session has CLA that helps burn fat… Dont know how much I believe this.
    I take L cartinine and Yohimbine currently and BCAA but didnt know about the insulin spike until I read your article :(

  • Rouge Surreah

    Hi Roman,
    How does one find out how sensitive they are to insulin?
    Also, in terms of putting etc. into the coffee. I like cream in my coffee, but only 2-3tbsp which is about 60 cal. Would this spike insulin? Or would stevia?
    I have read that HMB is a great alternative to BCAA’s that does not spike insulin and is more effective in retaining muscle mass. Thoughts?

  • Great post, building intermittent fasting into my daily routine is pretty much the only way I can stay lean all year round, I’ve also found it frees up my mornings to focus on work rather than thinking about breakfast or the snacks I’m going to have before lunch!

  • Hey roman, I have a question about one of your answered questions. Specifically the one about working out in the morning.

    Does this “anabolic window” stuff really exist? Or is it another marketing tecnhique to promote and increase sales of post workout meals and protein shakers?

    Kind Regards,

  • George

    Hello all,

    I decided to start IF, with the 16/8 path, but my schedule is as follows:

    Work from 9 till 18.30 and excercise from 19.30 to 20.30 or 21.00

    I cant workout in the morning, so that is out of the question. The most suitable feast window is 14.00 to 22.00 but only my second meal is after workout. Is that OK?

    Do you have any othe more suitable 8 hour to suggest?

    Thanks in advance,

    P.s. wherever I read about IF, I havent seen anywhere about daily calories consumed. Isn’t there a general rule on this? Fyi – I’m looking to lose fat out of this!

  • Joseph Lewis DeLisle

    Roman, Ever sense I started engineering the alpha my breath has been bad. I did some reading and found out the high fat diets can lead to this. Have u ever had a problem? This leads to my follow up questions does gum break fast?

  • JC32

    Hey Roman,

    Here’s a difficult training/work schedule, Working from 3pm – 7pm Mon – Fri. Training is Mon – Fri 7:30pm – 9:30pm and Sat 3pm-6pm and also training Mon, Wed, Fri from 12pm – 2:30pm? Is it even possible to fast with this type of schedule? I am intrested in IF for fat loss and getting extra lean (low single digits bf%) as a lot of what I do relies on great bodyweight strength. i.e. gymnastics

  • Ash

    A recurring experience I’ve had with fasting is that under some circumstances (sleep deprivation or post workout) prolonging the fast leads to brain fog (suspected hypoglycemia??).
    Is fasting while getting less than 6 hours of sleep or having sleep debt over 2-3 days usually lead to decreased energy levels and mental clarity?

    Would really appreciate some clarity on this.

    Thanks Roman,

  • Àd Nan

    thanks for your effort
    could i workout in eating window ( 8 hours) ??
    Would this reduce benefit of intermediate fasting?

  • Tracey

    I have been fasting from 8p to 12p for about a month now. 12-8 , i eat whenever I feel hungry, usually 3 -4 times. I work out at 8:30 am before work. I havent found it difficult to wait til 12 to eat (unless I have a very hard workout). If I do, I just eat a half hour earlier and adjust the eve time. The issue I am having consistently is 3pm funk. Like i have the flu and I am exhausted. I have a snack and green tea, but it takes 1-2 hrs to feel human again, also I have been waking at 4 am and having difficulty falling back to sleep. Any suggestions?

  • Name

    is it acceptable to have my eating window around lunch, rather than afternoon? [10 AM – 2 PM]

  • Kungfuboy

    Hi Roman, can creatine break fasts?
    Anyway ‘m currently reading Engineering the Alpha and i have to say it is , Downright awesome!. Good job man!

  • Raj

    Which bcaa brand do you recommend?

  • Raj

    Hi Roman,

    I am currently ending the second week of prime. And have followed the programme as suggested in the book. However one night I went off track where I ate pasta and burgers. Did this ruin my insulin reset? I did however fast the next day for close to 24 hours and them went back to my 16/8 routine. Please advise if I should continue and enter into the third week where I would begin to slowly reintroduce carbs into my diet.

  • Nadim Kabir

    Roman, I can only train in the morning. So I have a question about the proteinshake that you recommend to use during the workout. If I train lets say 08.00h in the morning can I have my proteinshake during the timewindow like 14.00h untill 22.00h? Can I do it like that while following your Engineering the alpha program?

  • Nerijus

    Hey, one quick question – I take Granade detonator supplement – two capsules almost right after I wake up. Does it break my fast?

    • That’s actually a great plan. Well done!

  • Marcus DeAmicis

    Hi Roman…I fast from 8pm untill 12pm , workout at 5am before work and supplement with BCAA’s after workout. My questions is in the PRIME phase or any phase of Engineering the Alpha, would it be ok to supplement with HCL Creatine anywhere in the routine?

  • Eduardo Urias

    People are over concerned about food.

    Just on side note: green tea may cause nausea and an upset stomach when you are fasting, so it might not be a good option for some people.

    Lots of water and some black coffee here and there. You cannot go wrong with that and your muscles WON’T melt down after 24h fasting.

    Nice post, Roman.

  • Joe

    Hey Roman how do you go about breaking a fast for an athlete who trains 2-3 times a day? I am a boxer and have cardio(2-3mile run or roadwork circuit in the morning), boxing/conditioning at 11am-1pm,
    strength training/skill work or possibly more conditioning in the evening?

  • James

    Just a note out there to other readers wondering about IF, I’ve been doing it since I started ETA nearly 2 months ago. Once you get used it, like Roman says, it’s not hard at all, and actually I find I both save money and am MORE satisfied from meals. Who wants to eat 1 bite of something multiple times a day? By putting your entire calorie intake for the day into 2-3 meals over only 8 hours, it means you can easily be satisfied each time you eat.

  • Pierre


  • Danny

    Since you like movie paraphrases so much , here’s one for fasting. ” Your bodies dying pay no attention , it’s only ordinary body death ” . Bought the book , in the prime stage.

  • Sam Nahrgang

    Roman in the first two weeks of Phase 1, you state 0 carbs on non-workout days; I’m finding it hard to find foods that have absolutely no carbs in them, what foods would you recommend. Also a lot of my meals end up being higher in protein and lower in fat than they should be, but this is because a lot of the fats listed in ETA have some carbs. And is there a cheat day in the first two weeks?

  • MarkyMark


    My goal is fat loss/recompisition rather than gaining size, and fortunately due to my work schedule I am able to follow the 16/8 pattern during the week and break my fast in the early afternoon post-workout.

    My question is what do you recommend for the post-workout meal. If you read Berkham he states stick to whole food, and make it the largest meal of the day—-keeping it nigher C and P and less F ( though I think that is for gaining size, and I’m sure he would tweak that for fat loss etc). But then many continue to feel that a higher carb and protein, maybe 2:1 (a shake lets say) is ideal in the post-workout window. I would think it would have to be the world largest shake to make it the largest meal at lets say 40-50% of total calories.

    I have been following kind of your FPFL recommendations, even post workout—higher F and P land less C, allowing for a little more C on workout days.

    PLeased so far, just wondering if I can tweak it a but more for the better,



  • Ben

    Hi Roman,

    Love all of your stuff! I had no knowledge about IF or your blog until a friend recommended I read ETA. I have, and I love it.

    I’m 6’2″, 205 lbs, and 13% body fat (have a 6 pack), but after reading your book I got my testosterone tested and came in at 419. I had been doing standard lo-carb high-protein diet, I’m taking up your protocol instead. My question is on the later phases, with the feast/famine eating model, if my eating window is 2:30pm-10:30pm, does that apply on my cheat day as well? Also, how many calories should I be aiming to eat on my cheat day as a multiple of my normal days? 2x? 5x? I’m more concerned with adding muscle than losing fat, but I assume the fast day doesn’t run counter to that, so planning to incorporate that as well.

    Thanks Roman, and thanks for all of the great knowledge!

  • Dan

    Hi Roman! Just got finished with your book this weekend – great read, and congrats to you and Adam.

    Few questions,

    1) I have to work out first thing in the morning at 6:00am. I know you recommend working out later so how do you recommend structuring things around a morning workout? Would you still recommend consuming the carbs at night, and how about post-workout drink?

    2) Also, I’m been following Fat Loss Forever program for the last few months. I’ve also been following the diet so I’m pretty much only consuming carbs on Wednesdays and Sundays (cheat days). I made great progress but have started stalling recently. Should I still begin this program at phase 1, considering that I’ve already been in a significant deficit calorically and carb wise?

    3) Can you elaborate on cardio recommendations for ETA? I don’t really remember reading any….



  • Troy

    I typically work out around 4:30am, would taking MP Assault pre be considered breaking the fast? By the way…loved Engineering the Alpha, it’s the reason I’m going to start IF and your program highlighted in the book. Hoping it can take me to the next level…6% BF!


    • john

      Mp assault has calories in it so yes you would brake the fast. Choose a pre workout without any calories or bcaa s in so you dont raise your insulin either or brake the fast

  • Roman,

    I’ve been trying to find a good “go to” article for intermittent fasting and I’m thankful I came across yours. I often get question after question as I try to explain the principles to people and now I can just print this out and give them a little homework and answering a couple quick questions. Thanks again.

  • Tony Peavey

    sadly, I workout at 9:30pm so I have to flip my diet and actually have the post shake as my last meal, fast till 2 and then break the fast with eating and then a meal at 6 then got workout a few hours after that,

    how does this affect the diet?

  • Mridul Murali (from India)

    As a follow on to the earlier question, literature in support of casein/or any kind of slow release protein, states that when you fast during your sleep your muscle breaks down. Is this plain bullshit or is there some science behind this?

  • Mridul Murali (from India)

    Hi John, your book was certainly an eye opener especially in terms of the science laid down bare. Had a question, considering I am in a ‘pesky’ job, my workout would be in the morning (7:30-9:00 AM) and my window for eating would typically be 10 AM-6 PM. That said, would it be beneficial/detrimental to have a casein shake before bed, considering that I would be fasting for 16 hours otherwise and hitting the gym first thing in the morning

  • Roman, for the cheat day, what time can we start/stop eating? full day or 8h window? Thanks!

    • Good question. On cheat days, I like a 12 hour feeding window. For me, 11-11.

      • OK! I am now closing Prime week #3, love the diet, great results already on insulin spike, sleeeep (big + for me), sex life, hunger, focus, skin, and off course body fat. Thanks a lot Roman!

  • RJ

    Hi Roman, I’m wondering what your take is on fasting for a strongman competitor. When I do my training it often lasts close to 2 hours and I usually need an intraworkout shake to keep me going. Depending on my work schedule I sometimes train before work and sometimes after. Is it necessary to follow 16/8 fasts every day or what would be the minimum number of days per week to fast in order to benefit from it? I can’t see myself maintaining strength through those workouts after a 12-16 hour fast.

  • Good post Roman. Great workarounds for those interested in fasting, and spot on in terms of accuracy.

    Another tip:

    Chew gum. It makes fasting way less of a pain and gives you something to ease your oral fixation.

    • t Meehan

      Gum either has sugar or artificial sweeteners, most of which are insulinogenic. Wouldn’t that be a problem if you are resetting your insuliin?

  • Andres

    How important is keeping a regular schedule with fasting? I’m implementing two or three 20 hour fasts throughout the week, but I don’t often have control over which two or three days I can fast on.

    Is the only risk that my ghrelin levels won’t adjust and I’ll remain hungry for longer?

  • Dan

    Wouldn’t it be better to not fast and make sure you get 3 grams of leucine 4-5 times a day to keep protein synthesis high? What about just supplementing with leucine during the fasting period?

  • If I implement a cheat day into my schedule, should I still utilize the 16/8 schedule for the cheat day? For example, do I do all my cheating in an 8 hour window?

  • bardziej

    I usually train in the morning (7-9 A.M.), so my ‘natural’ feeding window was 10 A.M – 6 P.M. Should I move my feeding window to 2-10 P.M. and skip pre- and postworkout BCAA’s for Phase 1 best results?

    And how about Phases 2-4?

  • I bought Engineering the Alpha and I’m currently in Phase I resetting my Insulin. Beside your recommended workout I keep training some muscles on sets (chest, biceps, triceps), my goal is to lose body fat but also gain extra muscle in those areas.

    In the first 30min after I wake up I drink a protein shake (35g Protein, 12g BCAA) 100% Gold Standard (ON). Why do I do that? Because Tim Ferris demonstrates in his book 4-Hour Body that >30g of protein in the first half an hour after you wake up accelerates your metabolism and increases fat loss. Then I keep fasting until 2pm.

    After I bored you with all these details, my question is:
    Does the protein shake break my fast?

    • Mike Alan

      Yes it does

      • vsync

        why would it break it? it’s protein, not carbohydrates. fasting is regarding ONLY to carbohydrates which break into sugar which replaces the ketones. and you want ketones. not sugars. protein is not break into sugars (if a reasonable amount is consumed)

        • KC

          It’s calories, which spikes your insulin, which diverts form the fat burning process

  • Awesome post Roman. Just recently started experimenting with 24-36 hour fasts, and I’m loving it.

    Also, as a side-note, I just listened to your podcast with Bryan Callen and it was outstanding.

    Keep up the great work.

    Jake Johnson

  • Piotr Damek


    Would you recommend to feast if someone is in the 1 phase of ETA(week 1- 30g carbs on Workout Days, 0g- on non-workout days)?

    Thanks in advance for the answer

    P.S- Few days ago I sent you the message on Fb. Did you get it?

    • Mark

      Absolutely not. I guess if it was recommended, he would have included it in that phase of ETA :)
      Gotta wait until week 5 Sunday (24 days to go and counting)

  • CubanCowboy

    R, bought ‘Engineering the Alpha’ last week, started Phase 1 this week (today’s day 5, on ‘Workout 2), following advice/instructions to the letter….and amazed by this glorious fact: yesterday (zero carb non-workout day) was the first day in 25 years that I did not have to inject myself with insulin! (i’m an insulin dep diabetic who, through your guidance, has begun a loooong overdue ‘reset’ process…btw: even endocrinologists vouch for intermittent fasting and upping one’s insulin sensitivity:)).

    With Big Thanks, Jorge

    • CubanCowboy

      Oops..I meant Workout 4!!

  • Miguel

    Great info John! How about “cheating” the fast on other supplements such as Creatine, multivitamins, fish oil, etc. Do they make a difference? thanks!

    • Shaked

      Even found an answer about Creatine?

      • tipoo2

        Creatine has no calories and should have no insulin impact.

  • Benn

    Do you stick from of fasting or do you practice say 16 hour fasts Mon to Friday. Good feast on Saturday then 24 hour fast Sunday

    • Sunday – feast/cheat day
      Mon – full fast, no food at all
      T – 16/8
      W – 16/8
      Th – 16/8
      F – 16/8
      S – 14/10 (mainly just out of convenience. I also don’t eat any carbs on this day)

      • Benn

        Awezomes yes this deserves a ‘z’. Thanks Roman.

      • Eduardo Urias

        Hi Roman,

        What time do you break your fast on Tuesday?

        Do you have you last meal on Sunday evening right?

        My PR is 34h fast, but did not like much of how I felt at the end.

      • Nikki Isbeingvague

        By any carbs, do mean veg carbs too? Forgive the seemingly easy question, I’m keto and just starting IF. Trying to figure out the balance.

        • Logan Waltz

          Fat causes no insulin response. Protein causes some insulin response and carbs cause even more of an insulin response. The primary purpose of fasting is control and regulation of hormones. Keep carbs for cheat meals or cheat days. They will only last half a day at most and will kick you out of ketosis for a few hours. If you want to include carbs at all in your keto diet, make them green veggies only. These are high in vitamins and low in carbs, they are also very slow digesting carbs, having the lowest insulin effect. The point of carbs in keto is misplaced concern for how healthy the diet is or because you lift weights and you need carbs as a quicker burning energy source for heavy lifts. If you want to know about carbs, just refer to glycemic index.

  • Guest

    I was just about to email you about Question #4, so this was timely.

    Turns out I was breaking my fast early and that may have tanked my leptin levels after I dropped all that fat (found that out thanks to ETA).

    I have a slightly refined question #4 though. Let’s say I workout twice a week in the morning, before work and twice a week after work. My eating window is noon to 8pm.

    Let’s say my training goal is re-composition/maintenance as opposed to fat loss. If I have a post-workout drink after those morning workouts, thus breaking my fast early, will the benefits of the PWO drink outweigh doing IF only 5 days/week?

  • Mike

    Roman, you’ve stated in a comment on your Athletic Greens post that you prefer 1g fish oil per % of body fat for fat loss, which is news to me. If you’re 20%, would consuming that much in the morning with 5000 IU Vitamin D and Athletic Greens break your fast? I tend to think it would. If it matters, I do 18/6 IF most days breaking the fast at 2pm. Thanks in advance for any guidance.

    Ps~ really digging Engineering the Alpha! Congrats on the achievement!

    • Thanks for the kind words about Alpha, Mike. Means a lot.

      To your question – I would say you’d want to have the fish oil at night, which some believe is better, anyway.

      So, AG and D3 in the morning, fishies at night.

      (also, if you’re taking 20g, use liquid – much cheaper)