There are many ways to do intermittent fasting (IF) or a "reduced meal frequency" diet - like skipping breakfast, eating only during a certain time-window in the afternoon, or even eating just a single meal per day (dinner).

I understand the psychological benefits of IF for some people who like the idea of holding back - so they can enjoy bigger and "better" meals later in the day. I have also managed to find some studies that prove certain benefits of IF (like improved insulin-response for diabetics), but that's not what I'm interested in.

I want to know if there is any evidence that - if I consume the same amount of calories on any kind of IF or "reduced meal frequency" regime - that this can actually lead to higher weight loss/fat burn in the end?

  • IF works because, when dieting, it's easier to eat X amount of calories in 8 hours than in 16. That's it. – Idri K Nov 14 '17 at 16:34

Currently there aren't any available studies that I can find that examine IF solely for weight loss/fat burn effects.

I can find quite a few studies showing the efficacy of intermittent fasting and calorie restriction on a whole host of body systems, but I can't find any addressing IF by itself, which means that you can't distinguish between weight loss with calorie restriction and weight loss with calorie restriction AND IF.

  • 1
    Yes, that was my exact experience too...plenty of studies on benefits of IF, but not a single one that would prove (or disprove) the difference in an equi-caloric setup - just plenty of anecdotal stuff across many different "broscience" sites. – user15206 Mar 23 '15 at 12:59
  • The closest I've found so far is a mouse study indicating that intermittent fasting decreases weight loss in laboratory rats compared to providing the same amount of reduced calories on a regular basis. – Sean Duggan Mar 24 '15 at 15:19


I have been doing IF for a year or so. In absence of any clinical trial and while I am not strictly answering your question, I am hoping that you really want to give IF a go. Consider this:

  1. By giving a large time gap between your last meal of the day and first meal of the next day, what will your brain and body be running on? We can only store 100 gms or so as liver glycogen, that can be used by the brain (muscle glycogen is actually not used to power the brain). The most logical answer is your body will become fat adapted. Your body will up-regulate the machinery to metabolize fat and your mitochondria should get more effective at burning fat.

  2. Add to that the fact that meal that you do eat are not sugary, processed carb types. You are sending a signal to your body again to get better at using fat as fuel and become an efficient fat burner.

You can then do a simple body-fat% check over a year to prove that you have indeed become an efficient fat burner. What I have learnt is that sometimes it's just easier to do an experiment of N=1 rather than rely on a clinical trial. When I eat a piece of cake loaded with gluten, I know how crappy I feel for a few hours - the brain fog. I no longer need an extensive clinical trial to convince me that gluten is a problem with x% of the population.

  • This is some interesting information (for someone like myself who is unfamiliar with IF). Do you any references for your #1 and #2 points? They sound reasonable, but I'd also like a wikipedia article or text book describing this if you have it. – Dolan Antenucci Mar 25 '15 at 2:12
  • 1
    Check out this link and there are heaps of research links in this article, if you go deep enough into the rabbit hole, you will find something. marksdailyapple.com/health-benefits-of-intermittent-fasting/… . Alternatively try pubmed. – Mark Dave Mar 25 '15 at 22:00

This was covered in: What's The Right Diet For You? A Horizon Special and there appears to be a few bits in the associated free interactive eBook. Essentially the thought is that intermittent fasting (IF) is a useful dieting technique, for people that they categorise / profile as "Constant Cravers", as the body will produce appetite suppressing ketones in the absence of food:

  1. Posted by Professor Susan Jebb on 13 Jan 2015 22:52

Rosie (152) and some others have asked about whether our intermittent fasting diet is the 5:2 diet. There are all sorts of variations on 5:2 dieting. Here we have combined the general idea of severely restricting intake on 2 days with the low carb concept. This is because avoiding carbs on these two days will encourage your body to produce ketones. These act as a natural appetite suppressant, making it easier to stick to the diet. This was especially important for our Constant Cravers who were always going to find dieting hard work. We encouraged them to do these two “fasting” days simultaneously so the ketone levels built up and they all reported that the second day was easier than the first.

See the comments.

  • 1
    I'm sorry, but how exactly is your answer relevant to my question? – user15206 Mar 24 '15 at 15:02

A very simple a short answer to your final question above is, IF speeds up the process of losing weight by spiking the release of growth hormone.

If to IF you add a ketogenic diet then you would maximize the fat loss by reducing the insulin presence.


You can look for Martin Berkhan's Leangains method here: http://www.leangains.com/

A guy did an AMA for that leangains program here: http://www.reddit.com/r/leangains/comments/1jjrci/former_berkhan_client_ama/

There is a book named, Eat Stop Eat, talking about the benefits of fasting, here: http://www.eatstopeat.com/ and here: http://bradpilon.com/

  • That's nice and all, but basically just marketing. The op was asking for evidence, specifically. – user8119 Mar 24 '15 at 13:42
  • It is very obvious you did not read any of the articles written in LeanGains. Intermittent fasting is a general term and it has many applications, leangains is one of them. He is a well-known individual in this community, and I personally do not have any obligation to market him or myself. There are references to studies in his articles in his website. I am giving him directions in order to learn from different sources instead of reading some material one of you copy pastes here. Please be respectful, we are trying to help after all. – Michael C. Mar 24 '15 at 16:31
  • @TuğberkKocatekin: You may have done a bit better to have quoted those studies then. :) – Sean Duggan Mar 24 '15 at 17:49
  • @TuğberkKocatekin: I didn't mean to imply your answer is marketing to push a pro-IF agenda. I meant to imply that your sources are biased in one direction (and one of them is a sales-page for a book, so...) and do not provide any studies without me needing to dig through the whole site. That does not constitute a good answer in the format of this site, in my book, and others seem to agree (see downvotes). – user8119 Mar 25 '15 at 9:36

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy