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Is Intermittent Fasting really as easy as people claim?

2

Replies

  • Posts: 393 Member

    Here's the thing. You absolutely cannot in any way shape or form not obey the laws of nature. You have to be under your maintenance calories (which it appears you've interchanged here with "necessary caloric intake") over the long term in order to burn stored energy (mostly fat, but also other tissue). You cannot create energy. You can only use it or store it for later use. Your source of energy is from the food you eat or from your tissue. It cannot come from nothing.

    It may sound trivial and obvious, but the problem with attributing fat loss to anything other than an energy deficit is that when people fail (or succeed), they won't really know why.

    IF deserves neither the credit nor the blame for fat loss or lack of fat loss. It is simply a way of eating and nothing more.

    For what it's worth, when I'm strictly working on cutting, I use IF as a method of eating so as to allow myself bigger meal portions for satiety - to control hunger. It is a tool, not a diet. There is no magic. It's not insulin spikes or lack thereof. It simply helps control my energy intake so that I use all of my food energy and some of my stored energy each day. If you don't use what you eat, you store it. If you use exactly what you eat (maintenance), you neither burn stored energy or add stored energy.

    People respond to things like this because claiming that it's not about calories is patently false.

    Preach!
  • Posts: 218 Member
    I did IF twice. The first time, I lost 15 pounds in a month? The second time, I actually gained 6 pounds. IF is a bit tough for me to do as I can't function without breakfast and work an 8-5 job. That means that my window was always 7-3pm which was not optimal for me as I am a 3 square meals type gal. I think IF works best if the feeding window does not interfere with your normal feeding schedule.
  • Posts: 414 Member
    I did IF twice. The first time, I lost 15 pounds in a month? The second time, I actually gained 6 pounds. IF is a bit tough for me to do as I can't function without breakfast and work an 8-5 job. That means that my window was always 7-3pm which was not optimal for me as I am a 3 square meals type gal. I think IF works best if the feeding window does not interfere with your normal feeding schedule.

    If I did IF and ate my first meal at 10:30, I could eat until 6:30 pm. If I get stuck in meetings until 7 pm, do I stop even though I may have only eaten 600 calories?
  • Posts: 1,306 Member

    ... If you use exactly what you eat (maintenance), you neither burn stored energy or add stored energy.

    I actually need to clarify this because somebody (like me) will notice the error and nitpick like I'm about to do.

    It would be more accurate to say this:

    "If you use exactly what you eat (maintenance) over a given period of time, whatever stored energy you burn will be made up in stored energy added".


    Obviously your body is not a perfect machine with minute by minute input = output. So your body is using available energy from wherever it can in the moment. Over a given window, if Input > Output, then Input - Output = Excess energy stored (in the form of fat and lean tissue - like muscle). If Output > Input, then Output - Input = Excess energy burned (from stored energy in the form of fat and lean tissue).

    So if your body is not digesting processing food (an oversimplification), it's likely burning fat. In any case, the body's means of managing energy is a complex, and amazing thing. But even with that, it cannot create its own. The energy balance is still a law of nature that we cannot violate.
  • Posts: 2,340 Member
    Of course it's true; if it wasn't then they wouldn't be allowed to put it on the internet, right? :laugh:
  • Posts: 2,028 Member
    Calories are still going to be king.

    I chose a variation of IF that works for me, and helps keep me in a (very small) deficit regardless of if it's a normal work week, or I'm traveling for work, at the track, or at a race weekend. I chose this plan because, when I'm on the road all the time, keeping accurate calorie counts was nearly impossible. This helped keep me from gaining, and I still had a very slow loss.

    If I want to lose at an appreciable rate, however, I still need to watch calories and eat within those limits. There's no magic window of time that will overrule how much you consume when you are eating.
  • Posts: 1,912 Member
    Not an IF er here but I'd say that you'd still need to track what you're eating so that you don't go over your calorie goals. Coz if you do, you will get fat regardless of how many hours you fast.

    That being said, I know one woman who has very successfully been doing 5:2 IF for the last few years and she no longer really logs her food but she knows that on her very low calorie days all she can eat is like a few carrot sticks during the day and one small meal at dinner to make sure she's under the 500 cal limit (or whatever it is, i'm not sure I can't remember, she did tell me when I was asking ages ago). It's kind of become intuitive for her, but she did track it when she started. Also the non-fasting days because we all know how easy it is to go way over in calories!!!

  • Posts: 2,325 Member
    LynnJ9 wrote: »

    If I did IF and ate my first meal at 10:30, I could eat until 6:30 pm. If I get stuck in meetings until 7 pm, do I stop even though I may have only eaten 600 calories?

    to stop would be very unhealthy. you need to eat all your calories, if you can`t fit them in your narrow window change the window a little or eat more often within that window. or bigger meals. but to function and maintain your body you need to eat all teh calories recommended by MFP (and add exercise cals) because that is what you should eat to LOSE the weight.
  • Posts: 4,370 Member
    I did it for a little while and considered it a fad and quit. I think people who binge and can't control their eating find it most helpful to have a small eating window .. they are all or nothing personalities.
  • Posts: 414 Member
    Panini911 wrote: »

    to stop would be very unhealthy. you need to eat all your calories, if you can`t fit them in your narrow window change the window a little or eat more often within that window. or bigger meals. but to function and maintain your body you need to eat all teh calories recommended by MFP (and add exercise cals) because that is what you should eat to LOSE the weight.

    Thank you. I wish my schedule would accommodate this style of eating. I know I would love to eat fewer meals with more calories.
  • Posts: 3,985 Member
    IF can be a great tool, and I do believe there are benefits to fasting (beyond weight loss). But NO, it doesn’t give you a license to eat whatever you want in the 8 hour window. You still need to be in a deficit
  • Posts: 178 Member
    The eight hour window in intermittent fasting is definitely not anything goes. For me it helps me eat less calories because three meals are put into a compact 8 hours.
  • Posts: 2,340 Member
    edited January 2019
    nowine4me wrote: »
    IF can be a great tool, and I do believe there are benefits to fasting (beyond weight loss). But NO, it doesn’t give you a license to eat whatever you want in the 8 hour window. You still need to be in a deficit

    I read this article:
    https://www.healthline.com/nutrition/fasting-benefits

    that makes all sorts of claims that seem suspect but they link to references. I followed a few and they are actual peer reviewed studies. Some are small and many are on animals with the assumption that it may also happen with humans. A skeptic could probably find a study that refutes the findings of each of them. It is very difficult to know what to believe.

    Bring on the woos (even though I said I am not sure whether to believe it or not). :laugh:
  • Posts: 154 Member
    I agree with many who have said IF can contribute to weight loss, but that is only in conjunction with a negative calorie intake delta against expetiture.

    To me this seems like an unsustainable fad. Are you going to eat this way the rest of your life? My guess is no. Once you start eating at different times, for one reason or another, your “diet” has the potential to be shot.

    It seems far better to simply say you are going to stay within a certain calorie window over the whole day, and it doesn’t matter when you eat those calories.

    To me IF seems like a solution for people who want to feel hungry and weigh themselves when they have the least amount of food in their bodies. That is not real weight loss; just cheating the scale to feel better about yourself. Real improvement requires actual effort.
  • Posts: 8,578 Member

    I read this article:
    https://www.healthline.com/nutrition/fasting-benefits

    that makes all sorts of claims that seem suspect but they link to references. I followed a few and they are actual peer reviewed studies. Some are small and many are on animals with the assumption that it may also happen with humans. A skeptic could probably find a study that refutes the findings of each of them. It is very difficult to know what to believe.

    Bring on the woos (even though I said I am not sure whether to believe it or not). :laugh:

    Click-bait title of the blog: "8 Health Benefits of Fasting Backed By Science" sure is catchy, isn't it?

    If they were *truly* "backed by science" words like "could" and "may" in these apparently 'proven' benefits wouldn't exist. That should be your first clue and, imo, completely negates anything else this blog has to say. It's completely contradictory.

    Animal studies do not always translate well when replicated on humans, and the small amount of human studies noted here are extremely limited and not proof of anything at this point.

    To be clear, I've been doing IF for over 4 decades, so I'm obviously a fan. The only benefit that I've seen is that it can help me control my caloric intake for weight management. Nothing more.

    Tl;dr? The best that can be garnered from this is that there might be the potential for some benefits. Might be potential. That's it. But these theories (because, at this point, that's really all they are) need to be subjected to rigorous human trials before "8 Health Benefits of Fasting Backed By Science" has a hope of becoming anything more than just disingenuous, misleading click-bait fodder.

  • Posts: 2,340 Member

    Click-bait title of the blog: "8 Health Benefits of Fasting Backed By Science" sure is catchy, isn't it?

    If they were *truly* "backed by science" words like "could" and "may" in these apparently 'proven' benefits wouldn't exist. That should be your first clue and, imo, completely negates anything else this blog has to say. It's completely contradictory.

    Animal studies do not always translate well when replicated on humans, and the small amount of human studies noted here are extremely limited and not proof of anything at this point.

    To be clear, I've been doing IF for over 4 decades, so I'm obviously a fan. The only benefit that I've seen is that it can help me control my caloric intake for weight management. Nothing more.

    Tl;dr? The best that can be garnered from this is that there might be the potential for some benefits. Might be potential. That's it. But these theories (because, at this point, that's really all they are) need to be subjected to rigorous human trials before "8 Health Benefits of Fasting Backed By Science" has a hope of becoming anything more than just disingenuous, misleading click-bait fodder.

    It definitely bothered me that one of tier claims was increased weight loss and higher metabolism, which I think have both been pretty thoroughly debunked. The longevity claim is hard to be sure about. Lots of anecdata seems to indicate that it applies to humans to a lesser degree, but most of the examples are of people who have a lifestyle that includes abstinence from smoking and/or drinking and mental conditioning that helps them handle what little stress they have very well.
This discussion has been closed.