14 votes

What should I know about intermittent fasting?

I know it's a big deal right now, but I don't know much about it.

I sort of stumbled into it by accident because I don't feel safe eating at work right now, so most days I don't have any food until I get home around 4:00 to 4:30 PM. I'm also usually wrapping up my evening and in bed by 9:00 PM, so I end up with a roughly five hour window in which to eat. Last weekend I tried to follow it even though I was home and found it surprisingly easy to just not eat until that time, even though it was safe for me to do so and food was available.

I was already calorie counting prior to this, but I noticed the shift to not eating at work accelerated my weight loss a little bit. It's also way easier to come in under my calorie count when I don't eat for most of the day.

Because it seems like this is working (though granted, I'm in the very early stages), and because I don't really have a choice in the matter given that I can't safely eat at work anyway, I'm interested in learning about the do's and don't's of intermittent fasting. As a beginner to this, what should I know? I am mostly interested in just making sure I'm not doing any damage to myself or creating any potential problems that I don't realize, so safety is my primary concern. Weight loss is a secondary focus, though less essential because I feel like I've got that down with calorie counting. Any insights or resources you know of would be appreciated.

18 comments

  1. [7]
    ahq
    Link
    I started with 16:8 IF and gradually switched to 23:1 or OMAD over a few weeks. I've been on one meal a day for over 2 years now. This is dinner for me, but some people eat just lunch or...

    I started with 16:8 IF and gradually switched to 23:1 or OMAD over a few weeks. I've been on one meal a day for over 2 years now. This is dinner for me, but some people eat just lunch or breakfast.

    In the very beginning. I drank a ton of water throughout the day, chewed sugar-free gum and kept myself busy. The mind wanders to eating when it's bored. Since you get back at 4:30pm, that's most of the day at work being busy, so you're good there.

    I did feel light-headed and slightly nauseous in the very beginning if I made quick movements, but it subsided in a few weeks. Make sure your salt intake is enough, and it wouldn't hurt taking a multi-vitamin pill every morning.

    After two years, my body doesn't react very well to eating outside my eating window. The handful of times I needed to, for social reasons, it ended with misery and pain in my stomach/gut. Also, the sensation of physical hunger will disappear almost completely. You might be tempted to eat or snack outside your eating window, but that will mostly be a psychological thing. Every time I broke a fast to eat a sugary treat because a friend asked me to, it did nothing to satisfy hunger, and felt forced.

    This goes without saying, if you have any medical conditions, it's a good idea to talk to your doctor first. Extreme changes in diet can and will have your body fighting to adapt.

    Good luck!

    11 votes
    1. [6]
      Adys
      Link Parent
      I want to switch to OMAD but my schedule doesn't really permit a set hour to eat at. How bad an idea is it to stick to one meal a day but make it sometimes lunch, sometimes dinner? One more issue...

      I want to switch to OMAD but my schedule doesn't really permit a set hour to eat at. How bad an idea is it to stick to one meal a day but make it sometimes lunch, sometimes dinner?

      One more issue I have with strict OMAD: before my skating sessions I can't eat a lot otherwise I'm bloated and cannot skate properly, don't feel well during the workout. If I don't eat at all then I am completely out of energy within the first hour. So I usually have one energy bar before going and sometimes one more during if I feel the first one wasn't enough. How would you reconcile this with OMAD?

      6 votes
      1. [5]
        ahq
        Link Parent
        Like most things in life, it's okay to tweak things a bit to fit your lifestyle. There's no reason you can't do OMAD on the days that allow for it, and something more flexible like 20:4 when you...

        Like most things in life, it's okay to tweak things a bit to fit your lifestyle. There's no reason you can't do OMAD on the days that allow for it, and something more flexible like 20:4 when you have skating sessions. And if you want to mix it up a little and have dinner on one day, lunch on the next, that's okay too.

        Your diet doesn't have to be perfect, as long as it's better than your current eating habits. There aren't any rules other than the ones you make for yourself - the ones that work for you!

        4 votes
        1. [4]
          Adys
          Link Parent
          I'm more worried that those feelings of hunger that "eventually disappear" will linger around if I don't stick to certain strict habits.

          Like most things in life, it's okay to tweak things a bit to fit your lifestyle.

          I'm more worried that those feelings of hunger that "eventually disappear" will linger around if I don't stick to certain strict habits.

          5 votes
          1. [3]
            post_below
            Link Parent
            It varies a lot by person but biologically once you get to the point where your cells switch quickly to ketogenesis you should have less hunger/blood sugar issues. The length of time without food...

            It varies a lot by person but biologically once you get to the point where your cells switch quickly to ketogenesis you should have less hunger/blood sugar issues. The length of time without food is the bigger factor in getting there (as opposed to the schedule).

            3 votes
            1. [2]
              Adys
              Link Parent
              Do you have to go keto for OMAD? I googled and it's unclear; I assumed OMAD was strictly about limiting the hours you can eat.

              Do you have to go keto for OMAD? I googled and it's unclear; I assumed OMAD was strictly about limiting the hours you can eat.

              2 votes
              1. post_below
                Link Parent
                Part of the reason it's effective is that you spend more time in ketogenesis. It's not so much that you have to, you just inevitably will.

                Part of the reason it's effective is that you spend more time in ketogenesis. It's not so much that you have to, you just inevitably will.

  2. mrbig
    (edited )
    Link
    It’s not necessarily more efficient than other diet fads, but it has one significant advantage: simple, clear rules that are easier to follow and harder to cheat than a complicated set of...

    It’s not necessarily more efficient than other diet fads, but it has one significant advantage: simple, clear rules that are easier to follow and harder to cheat than a complicated set of restrictions.

    That was my experience at least.

    10 votes
  3. Staross
    Link
    Some good info here : https://www.nia.nih.gov/health/calorie-restriction-and-fasting-diets-what-do-we-know Apparently there's not much risks if you do it short term. Long term isn't too clear though :

    Some good info here : https://www.nia.nih.gov/health/calorie-restriction-and-fasting-diets-what-do-we-know

    Apparently there's not much risks if you do it short term.

    Moreover, in the calorie-restricted individuals, no adverse effects (and some favorable ones) were found on quality of life, mood, sexual function, and sleep.

    Long term isn't too clear though :

    Most clinical trials with humans have been short (a few weeks or months), conducted in overweight subjects, and focused on weight loss rather than aging processes. The longest trial so far (CALERIE) lasted 2 years, which isn't long enough to learn about the long-term health effects of calorie restriction.

    7 votes
  4. [3]
    ohyran
    Link
    Sry if this is something you don't feel comfortable discussing, just say so if so of course - but why don't you feel safe eating at work?

    t because I don't feel safe eating at work right now,

    Sry if this is something you don't feel comfortable discussing, just say so if so of course - but why don't you feel safe eating at work?

    4 votes
    1. [2]
      kfwyre
      Link Parent
      Good question, and I appreciate your sensitivity in asking it! I don't mind sharing at all. I'm a teacher in the US, and my school has moved back to in-person learning. Because of the distancing...

      Good question, and I appreciate your sensitivity in asking it! I don't mind sharing at all.

      I'm a teacher in the US, and my school has moved back to in-person learning. Because of the distancing requirements, every available space in the school is all used up, so there isn't really a safe place for me to unmask and eat. We can go outside for now but soon it'll be too cold for that. Even without winter though, that option is still spotty. We've had a lot of rain recently, so a lot of teachers have been going to their cars to eat, for example.

      I've also decided that I'm more comfortable keeping my mask on for the duration of the day, rather than taking it on and off. I don't remove it until I get to my car at the end of the work day, where I seal it in a plastic bag and then sanitize my hands. The only time it comes off at school is the briefest of breaks to drink water, and even that I've basically scheduled out so that it's safest.

      7 votes
      1. ohyran
        Link Parent
        Oh right! Sry we have different rules for Covid here so I read it as a quick glance over an emotional issue! Sry again

        Oh right! Sry we have different rules for Covid here so I read it as a quick glance over an emotional issue! Sry again

        3 votes
  5. pew
    Link
    Developed an eating disorder doing this, just ate everything I could find before the window "closed". Was super fun in the beginning and it really messed me up after a year. I'm not doing IF at...

    Developed an eating disorder doing this, just ate everything I could find before the window "closed". Was super fun in the beginning and it really messed me up after a year. I'm not doing IF at the moment but the eating disorder is still there unfortunately.

    4 votes
  6. everydaycoffee
    Link
    Don't over think it! Read (and ask) enough to know you're being safe, but then keep it simple. I have done intermittent fasting on-and-off for maybe 10 years, and I think the main thing it has...

    Don't over think it! Read (and ask) enough to know you're being safe, but then keep it simple.

    I have done intermittent fasting on-and-off for maybe 10 years, and I think the main thing it has taught me is to not be scared to miss a meal (or two). But from reading a lot about it people also can feel things differently - so like any food/health related practise - do what works for you, and helps you feel good.

    Not eating till 4:30pm is actually what works for me! Even though I have been WFH since the COVID hit - so there is no reason why I could not be eating - I feel good in a fasted state (though I do drink coffee with milk, so a "semi-fasted" state), I like the structure, and I don't go crazy at 4:30pm and over eat.
    I generally look forward to a small meal (say one third of last nights dinner) to break my fast, and then I have a normal dinner around 7:30pm. I make sure I eat good nutritious food blah blah but thats another thing.

    Some people/blogs say recommend you take some vitamin supplements if you are going to keep this up for a long time (specifically electrolytes), and I have had periods of taking these with periods of not taking them - and I don't feel a huge difference. But YMMV.

    I am not following regimented fasting at the moment, (I have felt some anxiety recently, so in an effort to debug that I am eating a banana and some nuts mid morning) But from practising fasting I have no wish to go back to 3 square meals a day.

    I like to think of it this way... For a freaking long time humans did not have the luxury of 3 (possibly very diverse) meals per day,
    so not eating till 4:30pm? If you feel good you will be fine!

    4 votes
  7. Amarok
    Link
    I fast a bit differently. If I have a cheat day on paleo, I'll follow it up with a fasting day. Seems to work for avoiding weight gain.

    I fast a bit differently. If I have a cheat day on paleo, I'll follow it up with a fasting day. Seems to work for avoiding weight gain.

    3 votes
  8. knocklessmonster
    Link
    Really, don't break your fast if it's longer with something overly sugary or overly fatty. You may cause a sugar spike which will feel funny, or give yourself diarrhea (worst case scenario) or an...

    As a beginner to this, what should I know? I am mostly interested in just making sure I'm not doing any damage to myself or creating any potential problems that I don't realize, so safety is my primary concern.

    Really, don't break your fast if it's longer with something overly sugary or overly fatty. You may cause a sugar spike which will feel funny, or give yourself diarrhea (worst case scenario) or an upset stomach. The former has also been observed to correspond to increased risk of diabetes, but only in one study. Otherwise, I'm an advocate of keeping it simple: Only water, coffee or tea. If your goal is calorie restriction, take the coffee/tea however you want anyway, but don't use it to justify a frappuccino or something. If it's a larger metabolic thing, go strictly with zero. Personally, I do no known calories in my fasting window (exception: yerba mate, but I don't know how many calories that actually has, somewhere between 0-25).

    3 votes
  9. ryanatkn
    (edited )
    Link
    I've practiced IF for short periods of time, not as a lifestyle. I found it to be a really effective tool for resetting bad habits and returning to eating for nourishment instead of all of the...

    I've practiced IF for short periods of time, not as a lifestyle. I found it to be a really effective tool for resetting bad habits and returning to eating for nourishment instead of all of the other motivations. The most surprising part for me is that hunger and cravings are much reduced compared to eating the same amount of calories spread throughout the full day. In the dozen or so periods I've tried IF, my energy levels were sometimes worse, sometimes better than normal. I think it's key to listen to your body and not get overly focused on the rules and weight loss.

    I wasn't able to find any science on this, but I've seen anecdotes from women of unwanted or bad side effects. It seems to be one of "those" subjects full of blogspam and conflicting information.

    2 votes