A beginner's guide to intermittent fasting (2012) | Hacker News Reader

A beginner's guide to intermittent fasting (2012)

jamesclear.com

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For decades of my adult life I skipped breakfast, going against all conventional dietary wisdom. Having 3 meals a day just felt like turning my body into a conveyor belt that produces faeces. Now I feel kinda vindicated.

A few times I traveled with a friends who did the breakfast - lunch - dinner thing and after two or three days I had to opt out of either breakfast or dinner. I remember asking "how do you even manage to process that much?" and I just got blank stares.

For what it's worth, I'm 51 now and my body weight is the same as when I was 20. It just doesn't LOOK quite the same anymore ;)

I hate having breakfast, especially on work days for some reason. I feel ya

The work from Dr. Sinclair, and various other scientist seems to agree that its not just weight and body shape, you actually live longer and have less illnesses throughout your life.

Really fascinating stuff - the Lifespan podcast really changed how I think about all of this. I'm like you and haven't had breakfast in quite a while, but recently started skipping launch as well. A lot harder, but supposedly will feel about the same when my body adjusts.

Except that in his podcast he spreads a lot of bad science. I'd even call it misinformation. The work on Sirtuins role in health span and life span is, at most, inconclusive. Multiple studies on trans-resveratrol failed to show any improvement whatsoever (and yes, even when mixed with a fat to increase bioavailability). Maybe NMN does something, maybe not. It's not yet clear.

He states everything as facts while most of his own studies have never been successfully replicated, even disproven in some cases.

I'd take everything he says with a grain of salt. He's been called out multiple times by his peers, including his own friends like Matt Kaeberlein.

The most recent claim for bio availability of resveratrol seems to be that you need to pair it with piperine. Yep. Just like Curcumin.

I'm sure there's some science to back it up but it still brings to mind that old Marc Maron sketch.

He’s done a lot for mainstream interest in gerontology and longevity research but it’s pretty clear at this point that he’s financially tied to his position, there are multiple companies worth millions that develop products based on his labs research.

So he’d rather block everyone who tries to challenge him on Twitter and claim certainty on his podcast than be objective about the data.

_Obviously_ until conclusive double blind controlled studies have been done, this is all hypothesis.

The science behind the "longevity clock check" with by testing methaliations seems legit though doesn't it? I'm just a dude on the internet so would love some advice from somebody in the field.

But if that test is real, then it's a mater of time now isn't it? We wouldn't need to wait decades for people to die off so we can prove anything, we can just test with this clock, and in a couple of years we'll have results. I for one am quite excited about the whole thing.

While in his book he is less so, I think he seems pretty straight forward on his podcast by what has been tested with what, and how dubious the science of the various claims is. He admits a lot about some mechanism that they have no idea how it works, just that it does in various model organisms.

Anyway fasting and exercise have been linked to longevity for literally millennia by various religions largely unconnected with each other. I gather that we're now just trying to understand the mechanisms how all of this actually works.

I personally am trying the things on myself that have been proven to not cause harm, and seeing how it affects me. For now I've settled on reduced sugar in my diet, cut out gluten, stoped doing breakfast, started excising and do an occasional (2-3 times a year 4+ days water fasting). Seems to have kept the gray out of my hair for now - a lot of the friends in my age group already have it. Will see how that "no lunch" affects to me. All anecdotal of course.

What is the main mechanism behind the claim? I've heard it may have to do with the fact that catabolic conditions correlate to a longer lifepan. With that said, I'm sure there are people who (at least occasionally) want to be in an anabolic state, so I wonder how to balance those conflicting goals. E.g., can you get similar effects by creating a catabolic window for a few months every year?

I'm not doctor but I why skip lunch if it's hard to do? Eat something healthy and enjoy your time and days spent on the earth. I'm not saying ignore eating healthy or exercising. Those are key but punishing yourself to optimize for the possibility of living longer is a weird one. Especially since diet science seems to be far from perfect.

I generally agree with you, but for me I'm not necessarily trying to optimize for an ultra long life span but instead am trying to optimize for going out peacefully. I don't want my end years to be in some miserable, decrepit state in which I am unable to do much. In the end, all we can hope for is a peaceful exit.

What I gather is that eating less = living longer, and living better. Skipping lunch "feels hard" only at first, supposedly. Friends have been doing the no lunch thing for other reasons and report that after several weeks you just don't feel the need to lunch at all.

For me that sounds like a little bit of hardship now, for a big gain afterwards. I get the time to think about / prepare lunch back, and can now enjoy my dinners way more, as I don't need to really think and restrain myself on how much I eat then.

Obviously I wouldn't trade feeling bad for the rest of my life for a longer life, but it seems that's not what's happening, hopefully. It's more like "invest a bit of pain now, gain a lot of pleasure later" kinda dynamic. But I'm in the middle of this thing though so we'll see :)

Sinclair is getting in trouble lately for his questionable research. Look into the spat between Dr. Charles Brenner and Sinclair over unsubstantiated and low quality research claims. Sinclair finally blocked Brenner and others on Twitter because they kept calling out his frauds.

I like my breakfast late which makes me more often than not skipping lunch (weekends or vacations for sure) but never thought more about it. It definitely helps keeping the figure but I think I should gather more infos - like, meal records etc - before I turn it into a regular and conscious practice...

You and I are about the same age and I also have an almost identical body to when I was 20.

But I’ve eaten three+ meals per day my entire life.

50 years of age, 175cm tall, 63kg (or 5'9" and a little under 140 pounds)

People that maintain a low weight throughout life and eat 3 meals a day probably eat smaller meals than your 2 meals.

Ha! Same here, I stopped eating breakfast as soon as I became a student and kept hearing people telling me it's unhealthy... I just don't feel good when I have breakfast, I'm never hungry in the morning and forcing myself to eat breakfast is nauseating.

This is the way. ;)

I only eat a breakfast if it's like 3 hours after I've woken up, and consists mostly of coffee and maybe some eggs Benedict and if it's sitting in the sun in a little square on the Mediterranean somewhere.

I'm exactly the same. Go away with friends and eat like they do and so I'm feeling full all the time, which feels oddly bad. Then I'm going to the toilet all the time. Have been IF for the past 12 years, aged 49 and still same weight as when I was 20.

similar, but i got so good at it i got used to regularly going 3-4 days without eating at all and not really noticing/caring. as a result, my metabolism is shot and losing weight has been a real challenge. everything that went in stayed in for years.

My sense is that conventional dietary wisdom comes from an agricultural heritage — where we spent all damn day working the fields. Without that intensive labor, three meals seems to make less sense.

Indeed. I often skip breakfast without issues, but I once attempted to do this on a cycling holiday where my morning consisted of cycling at a moderate pace for several hours and I ended up collapsing asleep at the side of the road for about half an hour, then continued very slowly until I could find some food. What you're doing can have a big impact on how much food you need.

Ah yes, a bonk. Horrible experience. Happened to me once or twice, I never actually slept, but I had to essentially walk the rest of the way back. Always carry some gels, and fuel up properly at the start!

> Always carry some gels, and fuel up properly at the start!

Yes, lesson learnt! A friend I was with actually realised they had glucose tablets with them for exactly this purpose, but unfortunately they didn't remember until past the time where they were needed.

bonking for the first time is bizzare. i’ve been doing fat training because of sugar processing issues with the gels, and with focused effort and pacing i can bike through a bonk, but it is a delicate procedure

It is a lesson to be learned for sure! As my cycling ramps up so does my eating. I couldn't imagine surviving on anything less than 3 meals a day and copious snacking. Then again, I burn 6000-7000+kCal in a standard week of training which can be hard (for me) to replace. Your body will like you much more if you keep feeding it while riding!

I think you can train your body to deal with it. I used to hike a lot. I realized I felt a lot better while hiking if I didn't eat. I'd get up at say 5am, hike, and not need food until around noon before I bonked. It took work to get there. When I was younger, I'd get hypoglycemia if I didn't snack every hour or so. When I started hiking, I could go about an hour before I'd feel lightheaded. I got sick of it and started pushing through the wall. It was rough, then things started to change. After that, my eating habits changed even when I wasn't hiking. I got down to my ideal weight for the first time in my life at 40 years old.

That weight and the shape I was in allowed me to meet my wife. Unfortunately we like to eat garbage and now I'm back where I started at 47. It was a healthy 5 years though.

It was eye-opening once I started tracking my calorie intact and adjusting until I was in balance to realise just how far off typical dietary advice was for me. Especially as I was actively powerlifting at the time, and forums were full of advice about the massive amounts of food I "needed".

UK NHS still say 2000kcal for women and 2500 for men, but for me after actually counting and tracking my weight at different intake, the balance was ~1800-2000 when exercising 5 times a week including 3x1 hour long weightlifting sessions.

Of course for some men 2500 is fine, if you're actually active. But I've found most people overestimate how active they actually are because they do some sports outside of work. Without actually being in a physically demanding job, odds are you're not "active" in any meaningful sense (of course there are exceptions).

2500kcal was on the high end of my bulking intake when I wanted to add weight for my lifting.

> Without actually being in a physically demanding job, odds are you're not "active" in any meaningful sense (of course there are exceptions).

That's a curious conclusion. I and most others in my circle of friends are active in a meaningful sense, at least based on my definition of "meaningfully active". Most of us are in desk jobs, and none that I know have what I would define as a "physically demanding" job.

In the context of calories burned, most people in office jobs will fit firmly within ranges usually given for sedentary people. It takes a lot of physical activity outside of working hours to make up for an office job.

E.g. for me, an hour of high intensity exercise five days a week still placed me firmly in the sedentary range.

Part of the issue is that we tend to "forget" about the hours spent at work when evaluating if we consider ourselves active.

I haven't really looked at sedentary ranges, can you point me to the guideline you reference? Are they based on calories burned during an activity, amount of activity, time in HR zones?

As for intensity exercises, unless you actually measure your activity it will be difficult to estimate exactly how much time you're active inside of your hour exercise. I would guess a lot of people will over-estimate how much active time they really had. For example, weight lifting would be on the low side, HIIT classes somewhere in the middle and running/rowing/cycling on the high side.

I think it is even more complicated. When I was having after work activities that required me to walk to places, load/unload shelves, water the garden etc, I started loosing weight more then when exercising. And all those activities were not intensive at all. I was moving little bit a lot of time, basically.

Same goes when I go for hikes in summer. I am loosing weight, but I am walking at comfortable pace max.

I did not felt hungry at no point either. I dont know what it is, but intensity is not the only factor.

Wearing a Fitbit 24/7 was enlightening in terms of seeing how little activity it takes to get a fairly substantial increase in heart rate, so yeah, just amlittle more activity sustained over hours can make a huge difference.

It's been a long time since a looked at it in any detail, but a quick search for "calories burned sedentary" gave me a page full of calculators and estimates.

Looking quickly at a few of them, they mostly have tdee estimates for my age now that were still to high for me at the peak of my exercise fitness a decade ago... That includes the calculators trying to take weight and height into account.

The issue is that most of these are repeating and deriving categories based on guidelines set at points in time when a much larger proportion of the population had jobs that involved physical exertion.

And so you can be much more active than average for todays population and still be considered sedentary relative to the activity levels assumed in guidelines.

E.g. the UK NHS guideline of 2500 kcal for an average male would take me adding a couple of hours of walking during the day to reach despite exercising more than average...

And I'm sure you're right that people's failure to estimate their activity when they are exercising or being active is also a big part of it.

> ... the balance was ~1800-2000 when exercising 5 times a week including 3x1 hour long weightlifting sessions.

I see you added a couple more details to your post. Weight lifting sessions really aren't that productive as far as calorie burn is concerned. I pulled a random 30m weight workout and my avg HR was just over 50% resulting in approximately 130kCal/hr burned (estimated based on HR, actual could be a bit higher but unlikely to be higher than 200/hr), which does not come even close to cycling. My average calorie burn for a recovery ride is about 500kCal/hr, 575kCal/hr for endurance, 750kCal/hr for tempo and 975kCal/hr for threshold. Recovery/endurance are sustainable basically for an entire day (barring discomfort and boredom), tempo for 3-5hrs and threshold for <1hr (the 975kCal/hr effort was a 40 minutes). Cycling values are calculated from measured power output and and assume approximately 25% metabolic efficiency. My numbers are also on the lower side because I'm smaller (smaller typically means less power and so fewer calories).

> 2500kcal was on the high end of my bulking intake when I wanted to add weight for my lifting.

I would be surprised if I averaged less than 2500, though I haven't tracked in a long time. I can always feel when my intake isn't enough. My workout related output is 5000-7500+/week which is probably higher than average, though the low end is fairly well in-line with someone who runs/rides 5+ times per week. To your point, 2500 for an 'average' male is more than likely on the very high side.

> Weight lifting sessions really aren't that productive as far as calorie burn is concerned.

That's kinda the point. Very few people do high intensity workout very often or very long. Most people who think they're "active" are actually not burning all that much. Weight lifting can be quite intensive. Mine usually are at substantially higher HR than 50% unless I'm going for a 1RM. E.g. I'd do power cleans into press for reps quite regularly, and that gets brutal. But for most people they're not because most people take their time and don't push themselves to progress very fast towards the limits of what they could lift. But even for someone who takes the lifts seriously, sure, it's not going to compete with someone who takes cycling seriously for calorie burn. But then again, most people don't push themselves with cardio either. The proportion who pushes the limits in pretty much any given exercise regime is tiny.

> I would be surprised if I averaged less than 2500, though I haven't tracked in a long time.

You're quite likely right you're above that if you do a lot of cycling.

I would go even further and suggest that most of the social ills we deal with in the United States are a slow, painful, halting transition from rural to urban life.

These modes of living require very different heuristics and patterns and it’s not surprising that we encounter all manner of pathology as we transition.

When I was a teenager, my family went to a family reunion and stayed with some relatives who had a farm.

They ate four meals a day.

Diet, and wisdom are hard to put in a sentence together with a straight face. It seems this area is fraught with misinformation and disinformation. We're told to eat small amounts regularly, were told to fast intermittently, we're told to avoid carbs and eat fats, avoid fat (OK that's old), calorie count, and calories don't really matter insulin does. It's very very confusing. Is the jury still out on this? is it too subjective? what is the reason that explains why if you ask 10 people you get 10 answers for what you should do to have a good diet and keep weight down?

Same I have never had breakfast and all this time I thought I’m doing it wrong. My problems have been that I’m more on the skinny side and can never put on weight.

I'm very similar to you and your history.

I'm 41 now and my body weight is still like when I was 20.

Same, when I was a teenager breakfast actually gave me the runs if I ate too early. Yet my mom never let me skip even though I constantly tried too.

Breakfast food is hands down my favorite food, I just eat it for lunch or dinner now ;)

Same for me, my breakfast is coffee.

I "treat myself" and eat breakfast when I go on holiday, as I tend to be more active during those few weeks, but otherwise I have two meals a day.

I do the same!

And then since I broke my breakfast fast, I wake up hungry every day on holiday. I have to push through morning hunger pangs for a day or two to get rid of them (when I'm back to not-holiday).

I'd say yours is as much anecdata as mine. I've skipped breakfast for years at times and the only thing with calories between 10pm and lunch was the milk in my coffee (mentioning it because it might invalidate the whole thing, but not talking about daily morning coffee) and I didn't lose any weight, despite not being overly hungry at lunchtime and eating massive portions...

I've found that the 2 meals per day, eating lunch and dinner and then not eating again for 16 hours, is by far the easiest "diet" I've ever followed. It doesn't really disrupt any cultural norms around eating dinner (especially important with kids and getting that time together every night), doesn't require too much movement in terms of food you eat, and is very simple to follow. I think it can also have a bit of a flywheel effect in that you can start out eating your normal portions/food for lunch and dinner and will lose weight since you're cutting out breakfast. Once you get going, you start to say "maybe I'll just have some veggies for lunch today" and start doing that and start to lose even more and feel better. Compared to counting calories, counting macros, diet restrictions, etc. the guardrails for IF are incredibly simple to follow.

Once you get into the pattern, it's not even that much of a morning struggle, though the first few weeks may be if you're used to breakfast.

The one hiccup I have is my kids still eat breakfast and I prepare if for them, so it's sometimes hard not to grab a few bites!

I find that it helps to drink several glasses of water in the morning. Many times, the body is more thirsty than hungry. Then I have no trouble making it to lunch.

Why do your kids eat breakfast? Do they want to?

Just started doing this (again) two weeks ago and am down 4 lbs already. All I do is skip breakfast, and be a little aware not to gorge when lunch/dinner comes around, and then stop snacks (other than maybe a pickle or something) after dinner.

It really depends on the person, for my wife, she just calorie counts and can shed the pounds with little problem. I can't stand being constantly hungry and not eating until I'm full, and dealing with hunger in the morning until lunch is only a mild annoyance. For her, she needs regular food or she gets really hangry. Different strokes.

Funnily, I never ate breakfast until I met my wife, and because she's a breakfast nazi ("Most important meal of the day!!!"), I started eating breakfast, and struggled with weight over the years since then. I never had weight issues before that. So I'm dropping breakfast (except on the weekends, as it's a group thing for us to have a big breakfast, but then I skip lunch) and we'll see how it goes :)

The first week or so was rough, but yesterday I ate oatmeal for lunch (with walnuts and blueberries and slice banana) and then had a Factor meal (very tasty, not a shill!) that had lower calories than my usual dinner, and I was totally satisfied. That was like 1/2 the calories of a normal day previously and I had no hunger - so weird and awesome!

It's remarkable (or maybe not?) how much of a similar experience I've had with my own diet, in relation to my wife. It's the exact same narrative between us -- she needs breakfast every morning, whereas for me I'm used to just skipping it.

When I join my wife on a daily breakfast schedule, I feel like I'm just needlessly eating food when I know I don't have to. But for her, her mood palpably worsens within an hour or so of not having a bite in the morning.

On weekend mornings and vacations, I'll indulge in nice hearty breakfasts, but for my average workweek, no need!

I'm with you and OP!

But as I mention in a comment elsewhere here, if I indulge in a breakfast I will get hunger pangs the next morning (or two). Which leads me onto "needing breakfast". If I push through and just do my coffee and cream, I can get back to not feeling hungry in the morning (no hunger pangs) and back to [my] "normal".

My philosophy is: I eat if/when I'm hungry, not because "someone" tells me I should. "Someone" might be society. Also "Breakfast is the most important meal of the day" is marketing BS started by Kelloggs(?I think?) to sell cereal.

I'm on the opposite side of this with my wife. She can go 5-6 hours after waking up without food. I can... but it feels miserable and like my brain doesn't really start working until I eat.

On the flipside, I can eat my last meal of the day and go 7-8 hours without food until I sleep. She can't, though; she'll get severe hunger pangs or be light-headed.

So it seems like I should have breakfast + lunch, while she should have lunch + dinner. But being out of sync like that is unbelievably annoying in a relationship where you share / eat the same foods.

Does black coffee break the fast? No sweetener, not a flavored coffee.

I'm no expert, but everything I've read says coffee/tea is ok. I drink tea (love coffee, don't love what it does to me!) these days, and I put a bit of cream in it which is technically cheating, but seems fine so far.

it doesn't break it

No.

I'm very similar to the OP. I rarely eat breakfast. If I do, I can expect my body to have hunger pangs the next morning at breakfast time. However, black coffee doesn't affect me (I even add creamer so I get some morning fat sugar fuel, but not much). I also stopped drinking alcohol but a few times a year. If I drink alcohol after about 6 pm, I will get hunger pangs the next morning. I've never been overweight in my life and I stopped eating breakfast after high school.

I skip breakfast as well but I have to admit I put a little extra half and half in my coffee, but half and half is pretty low on glycemic load anyway.

Has anybody here experienced more impulsive behaviour as a result of intermittent fasting? More internal anger, being rude or impatient with your peers or children much more often, etc. I was on IF for 2-3 years, and while I gained a lot from the mental clarity, I also admit turning into an uneasy person within.

A quick google provided a 2020 paper that tackles this same question: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7381251/

Not just with IF, but also low/no carbohydrate diets because the lack of free glucose results in the release of cortisol and adrenaline, so it makes sense. I did low carb for a few months - at first it caused some issues but eventually I seemed to have adapted.

Yes, "hangry". I try to be aware of it now and then it's usually fine, and if it isn't I eat a small meal (some fruit or a protein bar)

Mine is pronounced enough that I've had romantic partners make a mental note to have snacks for me. It's pretty incredible, I can feel myself getting irritable, and within 15 minutes of eating something my body just relaxes and I'm back to being my charitable self.

That's not very surprising, you're weaning/rehabing from food, a lot of things can happen in your metabolism.

Not to mention serotonin is made in the gut, the brain burns a lot of calories too.

Also, most women I know are just uneasy to be with when they're hungry.

There's some rumor on the internet that IF might increase testosterone levels.

It might raise it in the short term but lowcal and fasting lowers free T in the long term. But lowering bodyfat helps with testosterone levels. Pros and Cons

I have noticed that too in myself occasionally. I do 16:8 IF and can eat after 6pm, and I notice sometimes around 3-4pm or so, I start getting “hangry” and impatient with people. It’s not all the time, but enough to where I notice that pattern in myself.

"Becoming easily irritated, tearful, anxious or moody" is one of symptoms of low blood sugar level.

I don't notice that effect from IF, but I definitely notice irritability when I'm restricting calories and actually losing weight.

tl:dr: shift your window.

I did 18:6 for about 6 months a decade ago and noticed the hangry effect (as did my wife and kids!). I went from 232 to 190 lbs though, placing top 5 in triathlons, so the method undeniably works. It's been 10 years and I found myself back at 225 and decided to get back on the IF wagon in December, with one modification: I stop eating at 9 pm and start at 3 pm, so by the time I encounter my wife and kids, I'm not hangry.

Curious what your initial eating window was?

Working man hours, not eating until home, so more like 5 pm to 10 or 11 pm.

The study says they fasted for 20 hours. That's well beyond what most people do. I do a 16:8, personally (which, is really just skipping breakfast), and if I don't eat by 1:00pm (which would be 17 hours), I'm a monster.

I've been skipping breakfast for over 10 years now, so I honestly don't remember how I was previously. Maybe I should starting eating it again as an experiment.

The opposite actually. I used to get hangry and be irritable all the time. I would also have blood sugar crashes if I ate carbs (hypoglycemic). Switching to 18:6 completely eliminated blood sugar issues and I am generally more docile.

If I skip breakfast I often eat like a maniac come lunchtime if I’m not strict with myself

I'm a "breakfast is my most important meal" person and therefore I eat breakfast and lunch but skip dinner. Works too!

There are several IF studies that say this may be the best way to do it. As the rising of the sun triggers some hormones that help process the food. So having an earlier 'window' has more benefits. Not a doctor. But something i have seen in my studies of this.

That’s interesting, I might have to try this out! Especially since my appetite is most reasonable at breakfast time, and becomes more gluttonous as the day progresses.

I’ve been doing this for 10 days now, since the day of your comment. It’s been really great. Energy levels are good, clod is solid, lost a bit of weight, and I’m sleeping really well.

I noticed similar observations. But I ascribe it to an increase of available mental energy which I unlearned to handle. Eating has a calming and sedating effect. Unhappy people like to eat much for that reason. It helps you sticking in your comfort zone and daily routine. If that sort of self-medication falls away I start to notice how that comfort zone is more like a cage and many rituals just voluntary chains. My mind then starts to fight back - in a clumsy and somewhat childish way, though, as I can't handle that little rage stirring up inside of me.

These threads probably attract mostly people who are dieting or looking to diet, so maybe it’s helpful to have an observation from someone who has never been overweight: I notice overweight people like low-to-no fiber foods and are unaware that they are only eating a few grams of vegetables per day. Maybe it is a good idea to make sure that every meal you have contains a real amount of it, so if you have 3 meals per day that every meal contains 15gr of fiber; or if you have 2 meals per day that each meal contains 20gr of fiber.

Honestly, it boggles my mind how someone can eat even a modest amount of fruits, veg., legumes, and whole grains alongside a generally healthful (not necessarily low fat, but healthful) diet and stay overweight. Not all of those foods every day necessarily, but I ran the numbers, and it just doesn't add up. Every chronically overweight person I know, once I know them well enough, seems to be putting down 500 kcal./day through some guilty pleasure like that pint of ice cream in the freezer, a super sweet creamy coffee drink in thr morning, a big slice of chocolate cake with lunch regularly, a large glass of wine with dinner etc. And it's almost _daily_.

Go try dramatically changing your weight and see how it makes you feel.

For the record I've never been obese, I'm in excellent shape and lift weights ~5 times a week. When bulking, eating enough calories to increase by weight by 25% requires significant effort. Similarly when I have do my cuts I find it incredibly difficult to get down to 10-12% body-fat.

My body clearly has a weight it wants to be at, and deviating from that requires a significant mental effort. I imagine someone obese trying to lose weight struggles the same way I do. The body wants to be at a certain size, and forcing it to change is difficult.

Maybe a better phrasing is "the body becomes accustomed to a certain size"?

The accepted term for that idea is body weight set point. It's still a theory, but a lot of people attempting to lose weight seem to independently discover the idea as they rubber-band quickly back to their pre-diet weight.

Dr Peter Attia, who has some interesting things to say about fasting, uses a completely different definition of “intermittent fasting”. What’s being described here is “time restricted eating” while intermittent fasting is periodic fasts of up to three days.

https://peterattiamd.com/ama11/

I can confirm through my personal experience that intermittent fasting works too. I used to be a personal trainer (15 years ago) and I have experimented a lot with diets and exercises. Back in those days, the fad was to stay in positive nitrogen cycle and eat minimal carbs - basically just eat protein+fats all day. That diet works (assuming you don't eat too much carbs) but it wasn't very good to stay lean. I used to find myself becoming fat eventually because I couldn't always count my calories (I am an endomorph).

Fast forward to 2020, I first read about fasting diets and was extremely skeptical about them because it went against my past knowledge of eating all day to avoid losing muscle mass. Nonetheless I started on it and never looked back. I can eat a lot in one meal so it is actually a perfect diet for me. I do it daily now - normally 8hrs eating and 16hrs fasting, and sometimes I take to extreme with 6hrs eating and 18 hrs fasting or 4hrs eating and 20hrs fasting. I can't ever skip breakfast so I just have my 1st breakfast at 530, then post workout I have my 2nd breakfast (Tolkien fan ;)) at 830. Then between 830 and 1300 I usually eat fruits and finally have my big meal (which is generally the same amount of total calories that I had in all my meals from 530) at 1300 hrs. And that is it!

Results: 1. Definitely lost body fat and there was no difference in my strength training. I mean I am not as strong as I used to be 15 years ago but that is because of aging. 2. Dishes: No need to do dishes multiple times in a day :). I just clean most of it by noon. 3. Energy levels: I find I am less bloated as compared to eating all day, so I find my energy levels are higher - except right after my last meal where it takes a few hrs for it to process. 4. The only disadvantage I have found is that I tend to have acidic stomach at times. This happens more when I eat spicy food for lunch, but if I stick to salads, rice, beans etc. then that is not a problem.

I do think this diet makes sense because evoluntionarily speaking we never had the luxury of eating all day. In fact, we probably had to starve every few days.

That said, if there is anything I have learnt reading nutrition in the past few years is that diets are complex and they don't always work for all so take my anecdotes for what they are worth.

I want to put in a good word for old-school calorie counting.

If you don't have good "gut intuition" for how much you're eating, you may find that IF just causes you to eat more in the time you are allowed to eat. CC tells you how much you're taking in, so the numbers tell you when you've eaten enough.

I often find that, when I stop at my calorie target (1500), I'm actually not that hungry... but I still have an urge to eat. Something I would have followed in the past. But with the number, I know exactly when I shouldn't follow that urge.

The requirement to stop and calculate before you eat also makes you a lot more deliberate about what you do consume.

It's definitely not the most spontaneous and fun approach, but I tried all the more spontaneous and fun approaches and CC is the one that is finally working for me.

A couple details: I jot down each day's calories in a Google Note on my phone. I add a number to the list for each thing I eat and keep a tally as the day goes by. I don't use a calorie counting app. I just use the nutritional facts if available, and if not, I Google "calories in x 100g" and use a food scale.

I've done CC a few times when I get close to being overweight.

Starting January of this year I cut my calories down by 1000/day, 7k/week, which is roughly 2 pounds (just shy of 1kg) a week.

It's now March 10th and I'm down 19 pounds in ~9 weeks.

Is it a bit tedious to count calories? Yeah, but it's perfectly effective.

Thermodynamically you're never going to be getting energy from nowhere. If you're consuming more calories than you're burning you're gaining weight; fewer you're losing it.

My goal is to lose another 5ish pounds so that I stabilize roughly at my current weight with a maintenance period of the next year or so.

Calorie counting is the one true answer.

Everything else is an approximation.

I used MyFitnessPal to count calories - makes it pretty easy.

Do you know how many calories you burn? Do you actually know how many calories are in your food?

I have a metabolic cart, and the answer surprises me sometimes on the former - just standing at my desk all day I burn >3300kcal. I actually went to talk to the guy in the Casey Neistat video about food labels, and almost bought a bomb calorimeter. Calorie counting, while not useless, is not very helpful.

https://youtu.be/hE2lna5Wxuo

I know approximately how many calories are in my food. Like I said I use MyFitnessPal to track it.

I know approximately how many calories I burn. In addition to using an Apple Watch I track my workouts.

And honestly this is good enough. If I target a 500 calorie per day deficit, I miraculously lose 1 pound per week. Which makes sense because simple arithmetic says that there are 3,500 calories per pound and 7 days times 500 equals 3,500.

It really is that simple. What on earth do you have a metabolic cart for? You wear that on your face all day every day tracking how much carbon dioxide you breathe out? And you really believe you’re burning 3,300 calories just standing? I could maybe believe that if you are in the morbidly obese BMI range.

Calorie counting is extremely helpful. Ask anyone who did it for the first time and suddenly realized they were eating 9 servings of potato chips at a time without even thinking about it.

I'm a nerd with more money than sense, what can I say! I trust the output of the device I have, and I do truly believe I am burning 3300kcal/day just standing at my desk, walking to the bathroom, etc. I eat 3500kcal/day pretty regularly, and maintain weight.

If you can target enough of a deficit and not be hungry, good for you. It's hard for most people. The input data is wrong, the output data is wrong/unknown, and one can only be hungry for so long.

video TL;DW: seems like it's basically safe to make an assumption that the reported calories in food could be 10%+ higher than expected, especially among packaged food. Larger restaurant chains like McDonald's and Subway seem to be slightly more accurate.

The surprising part was that it took the science guy 10 hours to calculate the calories for 5 food items ? Would be nice if we could get that down to minutes and accessible to personal consumers.

> The surprising part was that it took the science guy 10 hours to calculate the calories for 5 food items ? Would be nice if we could get that down to minutes and accessible to personal consumers.

Bomb Calorimetery is a PITA, I almost did a startup around this. The researcher in the video has a fairly manual one, there are automated setups that reduce this time, but they still cost $40k+ and require oxygen tanks, etc.

The even more difficult case for calories is something like a steak: how marbled is it? I could see some computer vision approach working.

I found CC the only thing that works for me for losing weight. Combining it with IF just makes it easier to stick with the caloric restriction. IF also does make it easier to maintain weight later on without CC. Of course, everyone is different.

I would prefer not to have to do CC forever so maybe this will be the way to go once I reach maintenance phase.

"If someone points out to you that your pet theory of the universe is in disagreement with Maxwell’s equations — then so much the worse for Maxwell’s equations. If it is found to be contradicted by observation — well, these experimentalists do bungle things sometimes. But if your theory is found to be against…thermodynamics I can give you no hope; there is nothing for it but to collapse in deepest humiliation."

- Arthur Eddington

Since James Clear's blog is getting shared because it's old (2012), I will share the OG post that kicked off the intermittent fasting trend: Leangains (2010).

Leangains didn't invent IF, but it did inspire more people in the last decade than anything else, including James Clear (it's the first reference he cites in this article).

https://leangains.com/the-leangains-guide/

> the OG post that kicked off the intermittent fasting trend ... 2010

The Warrior Diet book came out in 2001 and it had quite a following in the 2000s. It wasn't exactly IF but it was still focused on eating most of your food once a day in the evening.

Warrior Diet recommended for your dinner meal to be a meat and vegetable stew of some kind most of the time.

I'll admit it's been 15 years since I originally read Warrior Diet, but I thought it advocated a massive salad as the first part of your dinner followed by the protein source? I don't recall much mention of stew in the book, but like I said it's been ages since I read it. Not challenging you. Just curious since it has been so long since I read it and I'm trying to jog my memory.

I think we're both right, because the author recommended what you're saying: eat a big salad first, then try to have your protein source be a stewed meat of some kind so that the nutrients in the meat wouldn't be lost by the cooking process. They would be captured by the water in the stew, and more bio-available because they've been cooked.

It's great way to lose weight if you can keep yourself from overeating when your feeding window opens. It's the same result as calorie restriction.

I like stuffing my face instead of eating smaller portions. So I decided to go down to 1 meal a day doing 20/4; I lost around 48 pounds in 3 months.

Isn't part of the point that if you are doing one meal a day you can eat until you are stuffed and still avoid excess calorie intake?

And that is what I did. Sorry if it was unclear. You can still overeat in one sitting. It all depends what you eat, it's just tougher with one meal.

I m in if. For me I can eat all I want, but here is the surprising part, I do not crave as much as I used to. I am allowed, but genuinely not willing. Another thing I noticed, from experience, if I eat white bread, or cake, I notice it the next day being more hungry

I also like "stuffing my face" and I can highly recommend sticking to low calorie density foods. For example, I buy bags of frozen vegetables and add them to whatever other main course I'm having. You barely consume any calories, they contain a lot of micronutrients and the volume is enough for you to feel full. There are other similar foods if mixed veggies are not your thing.

I've been doing OMAD since the start of this year and loving it. I'm sat at a computer all day, why do I really need to feed this body if I'm not exerting the same amount out. I find when I eat lunch now, it's a real drag, and since I'm so full after it I don't even need dinner, and can usually wait until the next day around dinner time to find that I'm hungry again. I do get a ~30 minute brisk walk in daily but no way changes my hunger. Definitely see some weight benefits, probably lost > 5kg since doing it. And like one comment said about testosterone levels, yeah, I've definitely experienced it ;)

Edit: It wasn't instant, I did find it hard in the beginning, but once you're over the grind, maybe a week or two, it really is smooth sailing.

My brother-in-law does OMAD. He has discovered another advantage to it. He had to go to another city for a week for work. They put him up at a nice AirBnB, and... they gave him a $60 food per diem. $60 if you're doing 3 meals? Nice little treat, I guess. $60 if you're doing 1 meal? He eats like a king every night.

Now, in this case, it may not be helping him lose weight haha!

The beautiful thing about OMAD (I’ve used it to lose weight quite effectively several times) is that it’s rather difficult to go over your TDEE in one meal no matter what you eat. In fact, when you are trying to maintain a weight instead of lose, you often have to make a concerted effort to make even the minimum amount of calories to maintain.

It’s possible to lose weight eating nothing but an entire frozen pizza every day this way. Not that I would recommend doing that, it’s definitely not healthy. But possible.

Well maybe I'll give it a shot for a while. I've been skipping breakfast (mostly out of routine necessity), but I find I end up just eating a second supper late at night. I'm effectively shifting breakfast to lunch time.

Did you find any substantial cost savings?

Nothing dramatic - you eat less of course but if you’re the kind of person that cooks bigger meals and then eats the leftovers you either need to adjust how much you cook or plan to throw more away. It also lets you plan your one meal better so you often end up choosing something healthier since you’re putting more thought into the meal.

Everyone has different times they prefer to eat but I found for myself eating between 2-4 pm was the ideal time for me to avoid getting hungry in the evening and still be able to work well in the morning.

It takes about 3-5 days to adjust your body hunger chemicals so you end up having to fight through a bit of hunger the first few days but after that it goes away.

One downside is the inconvenience that it sometimes puts on interactions with others who might like to enjoy meals with you at times that don’t sync with your schedule. It would probably not work as a lifestyle for a salesman who did business meals, for instance.

You'd be surprised, I do a massive feed every night, but it does reduce over time. I find the tastes and aromas are more hightened after a fast, and everything tastes that much better. But the results would probably be so much more impressive if I didn't have the occassional beer/wine :|

Interesting. I took one year break from alcohol, just to make sure I am a master of my habits. Now I am back, drink red wine. So far keeping the weight. I noticed the food tastes better after fast, but so does wine.

"I do a massive feed every night"

What a great statement, haha! I'm going to start talking about all meals like this. Next I'll be asking friends if they want to "go do a feed" with me.

I've found this youtube channel, The Galen Foundation, founded by a cardiologist really informative: https://www.youtube.com/channel/UCUp8SWTLsEC6Mn8ExztMIjA

There's a bunch of talks, the earlier ones (Fat lies, Bittersweet Truth) cover how 'we' got to where we are, and the later ones (Fasting for Survival and the followup on Addiction) about intermittent fasting itself as a strong part of the solution.

Personally have started intermittent fasting also termed time restricted feeding, and early signs are positive and its not particularly challenging as far as hunger goes.

Most of this thread is about time-boxing your meal(s) and losing weight. An important aspect of fasting is that there are highly beneficial results to not eating - especially for 36 hours or more.

Most of what Galen Foundation promotes seems to be a low carb, low sugar, low manufactured (including processed vegetable oils), non-vegetarian diet combined with what ever level of fasting you feel comfortable with.

Interesting stuff: https://www.youtube.com/watch?v=RuOvn4UqznU

"Our life revolves around eating too much". God yes it does.

Once again I'll post my contra-indications. I tried intermittent fasting twice; the second time I got my doc to go along with ordering a second blood test after six months. My glucose and cholesterol were both worse. I gained a few points.

FWIW, I skipped breakfast most of my adult life, but after having kids (well, my wife actually birthed them) I remained overweight. Exercising and using fitbit to monitor calories is what brought things back under control for me, and I now eat breakfast.

I've always been a workout guy, but adding fitbit to the equation changed the way I think about food. For the better.

When I was exercising a lot(30-60 miles going per week) I unintentionally did time restricted eating and it seemed to work well for me. I tried it again years later while only doing moderate exercise and it caused me to start falling asleep after meals while I didn't see any positive effects like weight control. It took months to recover from the post meal sleepiness.

Time restricted eating isn't, to my knowledge, well supported my evidence in humans(Dr. Brad Stanfield covers this here: https://youtu.be/zC9_g01disc). So much misinformation these days in dietary science. Lots of frauds and scammers (i.e. David Sinclair) are pushing dubious claims derived from poorly designed or irrelevant studies.

I tried it when I saw a recommendation from the (US) National Academy of Sciences to look into it more because the anecdata looked promising. I agree with you: The result of looking into it more doesn't seem as good as the promise.

This is the one thing you don't see in all those analysis about intermitent fasting: Hard data about cholesterol, triglyceride and other blood levels. It would be good to have a large randomized trial with say 16/8 no-breakfast fasting which monitors those numbers.

Keto diets are notorious for this -- some people are, apparently, genetically unsuited to extremely low carb diets and their body responds by ballooning cholesterol levels and possibly some other issues (has been a while since I read about it). So they recommend that people getting on that particular diet do both self-monitoring and blood tests.

You could be experiencing some form of that. A lot of these ideas are very poorly studied and may be missing negative effects that occur in a minority.

I am currently alternate day fasting (ADF), which I'm finding very easy to do. Apparently the most popular form of ADF is a modified version where you can eat up to 500 calories on fasting days. I'm juicing on fasting days, which probably adds 300-400 calories.

ADF apparently is quite safe, sustainable, and healthy: https://www.healthline.com/nutrition/alternate-day-fasting-g...

I’ve been doing intermittent fasting (time restricted feeding) with 16:8 (I do at least 16 hours fasting and at most 8 hours feeding window everyday) for several years. It’s more convenient (as with others, I find skipping breakfast easy) and makes night times easier in a few ways (fall asleep fast, have a good sleep, etc.). Social outings in the evening could be an issue since I stop eating by around 6, but it’s not a big deal to break the rule sometimes. If I want to, I can easily compensate by eating a little later the next day.

With intermittent fasting, I didn’t lose any weight at all! I learned that weight management is about what you eat and how much you eat. A reduced feeding window can help in reducing calorie intake. But I do continue it because of the convenience and because I’ve read that it’s helpful in different ways not to be stuffing the body with food for a long time during the day.

I recommend this method of IF to people, and tell them to start with 14:10 or even 13:11, and then build up from there. I’ve heard from some people that they suffer from acidity when doing IF. I haven’t had that issue.

Yeah, 14:10 is very doable. That's eating dinner at 8pm then lunch at 12pm. I do that all the time without ever having consciously decided to do intermittent fasting. I wonder if stomach acidity issues has to do with what people are drinking. I imagine someone drinking acidic like tea/coffee (or even diet sodas) might end up with issues with this whereas someone drinking water probably wouldn't.

I've been doing 14:10 for about 9 months, and even that has had a big effect on my weight. And I don't even consciously realise I'm actually fasting at all.

You are correct that IF works because you eat less calories, there's no real magic there. The key though is that it is mentally easier than other diets to actually eat less calories.

Most diets fail because people need to make a decision about what to eat at the worst possible time - when they're hungry. Whether ordering at a restaurant or looking into the fridge at home, a regular diet expects you to make the healthy choice when your body is craving the bad food. With IF hunger is easier to tolerate because you can simply look at the clock and remind yourself you can eat in X hours. I also feel that it turns hunger into a good feeling, like a sore muscle after a workout, it feels like progress.

An added side effect I noticed when pairing IF with weight lifting is that when it was time to eat, my body actually craved the healthy food like protein.

I just started two months ago, I thought I would be grumpy because I love a big breakfast in the morning, but now after skipping breakfast I'm less hungry at 11:30 than before. So sometimes I have breakfast at 12 and sometimes normal lunch. Losing a bit more than a kg a week even though I'm still drinking beer on weekends. Just can't believe how easy it is.

This might be an individual reaction to fasting, but I always have headaches when I don't eat properly (skip meals, etc). Is this something that I would have to get used to when eating less?

Could be hypoglycemia, which has been linked to headaches.

One thing I've observed from going on / off IF several times is that trying to jump straight into the full fasting window can cause problems. If you normally eat on a 12/12 schedule, for instance, and try to switch straight to 16/8, your body will not appreciate it.

Try very gradually building up to the window -- add another 10 or 15 minutes between meals each day.

I got used to it by doing 12-12 then 14-10 then 16-8 then 18-6. I believe I did 10 days on each phase as 1 week seemed too "quick". It was just my moderate way of weaning myself off breakfast. I have tried the 24 hour fasts and I just can't make it and not be miserable.

The HN crowd should be perfect candidates for IF

Get yourself a very plain coworking space office, a big water container, and work on your passion projects or your startup.

Load up on water during the day. You should be going to the bathroom at least once every 2 hours.

If you are busy and not surrounded by coworkers asking for lunchtime it will be 6'o clock before long.

No coffee. Dont need it

I went from 165kg to 110kg with keto + intermittent fasting. Now steadily staying there. I'm still overweight but feel much better.

Wow, congrats on your results!

Been skipping breakfast for about 5-6 years now, and it's had a really positive effect on energy and weight, plus helps me keep IBS in check, especially when combined with minimal sugar intake.

But the by far best thing is to REALLY enjoy a nice lunch when you've been actually hungry before. Turns out I had completely forgotten what hunger feels like before doing IF, and it's actually a pleasurable feeling when you know you're about to break your fast with a great meal.

Before IF, I would often have lunch "because it is lunch time" and didn't particularly enjoy the food. Very different when you haven't eaten for 16 hours.

Want a real tasty meal, try 36 hours aka monk fast. I tried that 4 times and tried 48 hours 3times and 3 days one time since summer. 36 is the best. Not the easiest, surprisingly. But if I do longer, I can’t just eat anything I want when breaking it. The word from the wise about chicken broth is true, in my case. But 36 still not long enough to require easing out, and god it tastes great, whatever it is you are eating

Intermittent fasting works because you end up eating less calories. On the other hand, shifting your eating to earlier in the day while eating the same amount of calories leads to weight loss:

https://www.youtube.com/watch?v=LQThN6e4PD4

I don't have a reference to it handy, but I know Rhonda Patrick talk about this: it takes a minimum of three days fasting in humans to reproduce the effects seen in one day fasting in mice. Her theory is that their metabolism is much faster, and one day is a much bigger percentage of a mouse total life time than a human's.

I lost a lot of weight by skipping meals, but then got stuck. I then started logging my food intake, mainly to keep track of nutrients, make sure I eat adequate amount of fiber, etc... Since I was doing it I decided to be consistent and restrict my calories: my weight is linearly correlated with the amount of calories I eat. I still skip meals for convenience, because I get an energy boost and because it was hard for me to eat small meals, but I'm very conscious of my calorie intake and adjust throughout the week when I end up over or under eat.

You're completely discounting the effects of fasting on insulin levels. Low levels of insulin are correlated with higher rates of lipid oxidisation.

Not that this effect will outweigh e.g. an additional banana you devour because you're famished after fasting. But it is there. Counting calories is a good help in making sure you don't nullify it.

(https://www.sciencedirect.com/topics/biochemistry-genetics-a...)

Sure, but how much effect do all those "side effects" have in comparison to a significant calorie deficit or surplus? How applicable are those effect to the average person who wants to keep their eating to something relatively simple?

Do you think that any of those effects will be enough to maintain your weight if you consistently eat a 500 calorie surplus?

My issue is that a lot of people start doing "intermittent fasting" (less than 3 days) thinking they can eat all they want during the eating period, and that they will benefit from the fasting health effects shown in mice studies, but neither is true.

I would be very surprised if 500 kcal didn't register because of IF. Is that the claim though? I've been doing 5:2 for years and there they say "eat normally" on the off days. Don't overeat/compensate.

So intermittent fasting for ease of compliance? Yes, that I agree with. As stated above my issue is to let people believe they can eat all the food they want as long as they follow a magic schedule.

Yet another person acting like "calories-in calories-out" is the only variable in dieting. Good grief. There's a lot of psychology to it. I've lost a bunch of weight just eating 2 meals a day and make that "the law". I don't really count calories. I eat a small plate of food that is "whole" food and not crap. probably 600-800 calories most meals. Occassionally on the weekend I'll relent on a saturday to go out with friends to dinner or movie or something. Most people are getting their extra calories by snacking and eating huge meals when they really don't need to. That's no secret to anyone. There are techniques like IF that work for some people. There also seems to be some side effects as well of less inflammation and food cravings, at least there were for me.

Number of calories is the only option, but there are many techniques for compliance. I'm fine with saying that skipping meals and snacking helps some people compliance, hunger issues etc... and do it myself, but want to warn against the idea that one can eat as much as they want as long as they eat on a magical schedule.

I started intermittent fasting in September and I thought I would do it only to lose my corona weight gains. But by now it's a lifestyle for me that has so many benefits. To be fair, breakfast was never that important to me. I typically start the day with a few cups of coffee with milk and going to black coffee without milk was and is funnily the biggest price I have to pay.

To cut the junk food after 8pm has so many positive effects on my overall wellbeing - and let's face it, it is always bad food we eat at night, nobody ever comes up at 10:30pm "hey look at that nice apple."

I'll turn 47 next week and I have an almost perfect BMI again - something I hadn't had for almost ten years of so. And I still eat too much cake and chocolate in the afternoon and don't really starve overall. The only thing I can't get used too is the black coffee in the morning but that's a small price to pay.

Intermetting fasting is not a diet, it's a lifestyle and that's why it works so well. So overall I can just recommend it.

Coffee on an empty stomach is quite hard on the stomach. One thing I learned recently is that gut damage from unhealthy eating habits can accumulate over long periods of times, and symptoms manifest decades after. So if you notice any uncomfortable feeling from this habit (the all too common coffee diarrhea for example), it wouldn't be a bad idea to skip the morning coffee or at the very least prepare your gut with some food and water first.

> and let's face it, it is always bad food we eat at night, nobody ever comes up at 22:30pm "hey look at that nice apple."

You're probably right in general, but I grew up in a house with no "bad foods" available (we were allowed them occasionally, but they weren't kept in stock in the house). So fruit and rice cakes or maybe raisins were the late-night snack options. And while I'm definitely not as strict about this now, I will still quite often pick an apple or celery/carrot sticks as a snack.

I lost over 75 pounds with time restricted eating mostly just one meal a day.

I lost 30 pounds by eating smaller meals. Still had breakfast, lunch, and dinner. Skipping my afternoon snacks helped a lot too.

All these anecdotal stories and it all boils down to fewer calories.

How did you avoid eating more to compensate for missing out on the other 2 meals a day?

Can only fit so much in my stomach.

I eat at the end of the day and go to bed, so there also isn’t time to have another meal.

Intermittent fasting. A.K.A skipping breakfast

Haha this is what I thought reading the article. One thing I don't think was really touched on was exercise. Am I suppose to exercise during the fat burning period i.e. 12 hours after my last meal?

Sure, you get used it. I've been using time restricted eating for years, and workout in the mornings. It was hard at first, but I guess I adapted. I rarely feel hungry and have tons of energy in the mornings. I've gotten to where I try to plan strenuous activities before my first meal because I just feel like I have a more steady state of energy.

Many people like exercising just before they eat, especially if you're doing weight training. However, if you're _performing_, instead of exercising (like running a race) then you'll likely want to eat before you start.

I regularly do very high intensity Sports for 2 hours, after fasting for roughly for 20 hours straight

It feels normal, but it may not be for everyone

Keep in mind the Muslim elite soccer players that observe Ramadan and are doing it at the highest level

I am not saying IF is “junk science”. But the idea of it helps “burn fat” isn’t scientifically sound. Most studies I’ve seen saying the reason it works is because you end up eating less calories even though you’re not trying to.

most people who think they are IFing because they don't eat breakfast simply don't have a conscious overview about how much and when they are consuming calories. upon closer inspection it mostly turns out they do in fact eat little snacks at random times.

I'm doing 20h/4h for almost 2 years now. Which means i eat one meal a day, but that is split into two, first i eat around 11AM then around 2-3PM then 20 hours fasting. Most people thing that's insane, but the reality is, once you're done eating at 2PM, you don't have to think about food anymore for the rest of your day. "Ohh no, what am i gonna eat for dinner or for breakfast?", this is irrelevant. I've lost 10kg in 6months, without any real struggle. Now days i have a cheat day every 1 or 2 weeks, but i'm in a weight maintaining mode now. If i want to lose more weight, i have to switch into "strict mode", in general the amount of food i eat has a calorie deficit. On top of this i take vitamin supplements just to make sure i have enough, since i eat less.

> Most people think that's insane

To anyone starting IF I would advise not caring about what the average joe think. Most people are overweight, eat 3 times a day while the most strenuous activity they'll go though is getting out of bed in the morning, what they consider healthy/insane or not isn't relevant

I have done the same for over 3 years now and I have had fantastic results in every way. I spend far less time making messes in the kitchen and cleaning them. I spend less on food, I have more energy.

But I had a death in the family recently, and I gained almost 10 pounds in a few months.

But it doesn't matter because I am already starting to shed them again. This is the key most people don't understand about IF, that you get to keep this skill even when things go wrong, it's easy to right the ship after you have a problem.

Also, I don't want to pig out anymore (like I did before doing IF) and if I feel like eating extra dessert, have steak all week (or whatever), I can for the rest of my life without any issues.

I've used IF now for a few years and have enjoyed the benefits. I usually only eat dinner. Three observations.

1. It's not for everyone. Give it a try and see if it works. 2. Drink lots of water. 3. Try having a salad or a plate of veggies 20mins before eating your dinner. That helps me avoid over-eating.

While agreeing, I would add, when trying it, do it gradually. First give up snacks, then narrow the gaps, then skip breakfast while widening the gap, then narrow it again. Two weeks each step at least. When in discomfort go back a step. While doing so also change what you eat, also very gradually. If you are like me and hate salad, just peel a carrot, cut a cabbage, eat them. I don’t bother making salads. To me it is a tax to pay. I eat them cause I must. Over time I started noticing they taste ok, to ahungry person. But the real joy of comes after paying that tax.

Some advice if you find it hard to skip meals - you can drink things like coffee, tea or water. Skip the sugar of course, but it helps your stomach feel less empty to have liquids.

Many people are accustomed to having their stomach full all the time and associate the feeling of an empty stomach with something being wrong. I had a friend who couldn't go three hours without eating and said she would feel faint. It's kind of like how some people feel dirty for not showering every morning even if they aren't actually that dirty. But you can learn to stop associating these things. I have been intermittent fasting for years and don't even notice an empty stomach now.

Heads up. I did IF and low cal for most of covid. I lost weight but it really messed up my hormones. My SHBG rose thus lowering my free testosterone to the levels of a 90 year old.

I don't think there is a universal solution for every person. People have different psychologies. For instance for me eating more earlier in the day tends to work. That way I have digested by the time I want to exercise around 6pm.

Covid was a real hiccup in my health goals, gym's closed, loss of routine, and having my GF move-in and have to accommodate someone else's patterns really set me back (not blaming her, it's just easier when you only have to worry about yourself).

When I have rest periods, I naturally gravitate toward intermittent fasting because I don't like spending time preparing and eating food. I didn't know what it was until it became trendy.

Most of the time, I'm engaging in 4-5 hours of intense aerobic activity and three days of weight training per week. Unfortunately, if I attempt intermittent fasting, I am fighting fatigue and more prone to injury.

I also find my fasting with exercise leads to me being more susceptible to illness as well as injury.

I don't typically feel hunger or thirst much so I have to make sure I eat consistently.

Same situation, I maintain a strict eating schedule and meet daily water goals. It´s very easy for me to discount the benefits of eating and drinking water, and opt to focus on whatever I´m working on instead.

It's important to realize that IF is more than just calorie restriction. It's also about giving your digestive system time off to heal. Plus - when restricting calories to a small window you'll naturally change choice of nutrition towards proteins, good fats and less (not none, though) carbohydrates. Otherwise you'll feel hungry during the fasting period after a few hours.

IF works well. Been doing it for years too. 2 meals on most days and one meal sometimes. Just avoid eating too much for those remaining meals.

Sten Ekberg has a great channel on youtube about this. It worked for me but I've since fallen off the wagon with predictable results.

Question for anyone who might know: what are the benefits of intermittent fasting for those of us who are really thin, and having trouble keeping on weight with an already well-balanced diet?

I have a lot of nagging aches and some minor chronic health issues. Is there research on any effects there? Because as it is, I have trouble eating enough to power my moderately active lifestyle.

If you don’t eat enough, don’t eat less. However there is some research correlating periods of fasting and lowering inflammation in the body. If your aches and health issues are related to inflammation it might help but consult your physician first.

I'm not even close to an expert on this, but I've recently started weightlifting and it seems to help with some slight aches I had. I've also been eating more, though, trying to put on some weight.

It's quite interesting reading James' writing from 10 years ago, having read Atomic Habits (in which he talks about his self-publishing extensively). The site layout and theming, the writing style, the choice of subject... I can really see it being used as a case study in effective modern communication by future generations of students.

I think just getting rid of the habit of stocking up snacks at home itself might help immensely in scheduling meals.

Interesting that this has a name. I've been doing this naturally for quite some time now without knowing the science behind it; it just feels "right" for me.

Thinking about it, whenever I had a job where I ate lunch with coworkers (besides my breakfast+dinner combo) I noticed that I gained lots of weight.

I've been doing IF on and off since reading this article ten years ago. It's a decent way to lose weight, but if you play sports or do any kind of strenuous exercise, you need to optimize your meal timing really well, or your performance and recovery will suffer in a big way.

I try to eat at lunch and at 6 in the evening, cut down on the carbs, and exercise in the morning when levels of stored glycogen is low to get the body to burn fat. But I haven't been at it long enough to say if it works well.

Careful with your caffeine consumption if you start IF. Many people find they are more irritable on IF and fail to realize that their body processes coffee differently when they have an empty stomach.

The wording here always confuses me, why is it called intermittent fasting? Isn't all fasting already intermittent otherwise it would be called starving right?

Yes, all fasting is intermittent or else it becomes death by starvation which is something different.

I think the term "fasting" has become more severe since the term breakfast became commonplace. It comes with baggage that implies religion (fasting during Ramadan), medicine (fasting before surgery), or protest (fasting due to hunger strike).

They needed a term to reduce the severity and it probably could just have been "moderate fasting" or "scheduled fasting". "Intermittent fasting" won because the English language is cromulent.

https://news.ycombinator.com/item?id=30626772

Anecdatally - I've been on omad (one meal a day, just dinner) for coming up on a year. I only weighed myself once every couple of months at a friends house as I don't own a scale. Over the last year, I dropped 28lbs without much effort beyond adapting to the routine over the first month or so, and then gained 8 lbs. back over the winter due to being relatively sedantary, and adding alcohol back to my life. (red wine, whiskey, and worst vice of of all, cider)

This may seem like a small amount to lose over a year for such an extreme diet (~12% of body weight at lowest), but the number overlooks how much I really enjoy eating when I do eat. No snacks, no hidden sugar crap, but bulking size portions without desserts. An example would be if I had to eat fast food because I was out, it would be some gourmet organic hipster double fancy burger where all the animals involved were probably raised with music lessons or something, with another normal single burger instead of fries, and the idea of sugar water is absurd. Only eating at dinner, at least 75% of my meals include salad or large vegetable servings as well, so even if it's small, most eating habits don't include that, so there's a net trade off. So still a somewhat perverse meal size that would qualify as gluttony to an observer, but limited by OMAD availability. I can't say it's virtuous and healthy at all (a lot of chicken burritos), and it's less a diet or scheduling as managing ones tendency of abusing food, but since I'm not wired for moderation, this has been something that works.

I have a few black espressos every morning, and go until about 5pm or later before having a normal (if extra enjoyable) dinner.

First few weeks are hard, and I got through them with mint tea and chai tea (no milk or sugar) during the day when I was really struggling. I started in April, so the snow was gone and I could get out for walks at lunch, and I found exercise was the absolute best hunger killer. I avoid dieting in principle because I think it becomes a weird and pious substitute activity that appeals to a sense of purity I don't have. Starting in April felt right because every animal is basically starving by April anyway.

In terms of nutrition, it has been red meat once or twice a week, salad at most meals, high fat. Gyms were closed last year, so I walked an hour a day 4-5 days a week and threw in some occasaional dumbell sets on boring conference calls. I got about 90mins of extra productivity/HN from the time I would have spent prepping and eating meals, and coupled with work from home and no-commute, I added 3h a day to take on addtional consulting clients for short periods.

I'm still overweight (6'2/220), but it's controlled, my YoY billings are up 20% and I have a more appreciative relationship to food.

what about when being hungry makes you distracted?

If your diet is sufficiently arranged to contain as little carbs as possible, this disappears. I went from a heavy lunch person to forgetting to have lunch.

Does the amount of carbohydrates intake impact focus/concentration?

For me it noticeably did. Less carbs => better focus. Of course, anecdata, YMMV etc.

Carbs give you a sugar rush and then everything in the body goes into processing them, slowing everything else down.

You can easily test it, eat something like a subway sandwich. Record how you feel. Now take the exact same sub, but as a salad (no bun). You'll feel markedly different.

This all, of course, depends on a ton of individual factors like insulin resistance etc.

Your example seems to be about refined and simple carbs. Those do spike blood sugar. But a better diet would include more of complex carbs where the blood sugar doesn’t spike as badly as with a diet on processed and refined (fiber-less or low fiber) foods.

Before anything else, one of the factors to consider is adequate hydration. Sometimes people confuse thirst as a signal of hunger for food, and then start snacking or binge eating.

Another big component of hydration is electrolytes, especially sodium. Particularly if you're eating lower carb, drinking coffee, doing some sort of fasting, and/or exercising. If you're doing any of those things, the RDA of sodium is likely nowhere near enough for you.

For me it required both dietary and psychological techniques to deal with feelings of hunger.

- During my morning fast if I'm hungry I'll mix two tablespoons of psyllium husk with water and drink it. Fiber helps you feel full and in this form doesn't break the fast https://www.ifbuddy.com/nutrition/does-fiber-break-a-fast/

- Psychologically I remind myself it's OK to feel hungry. I reframed feelings of hunger from a signal that I forgot to eat to a signal that in a few hours I'll need to eat, as if hunting and gathering will take a few hours so my body is telling me to start now :-)

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