> The mean (SD) reduction in energy intake was -313 (509) kcal/d for TRE, -197 (426) kcal/d for CR, and -16 (439) kcal/d for controls
So — the time restricted eating group reduced calories more than the group that counted calories; but the resulting weight loss has the same cause: reduced calorie intake compared to before.
If there’s a take away here, it’s possibly that adherence to a calorie deficit using a time restricted eating plan is easier than adherence to the same calorie deficit by explicitly tracking calories.
If you can adhere to a calorie deficit through other means, you won’t lose weight faster by adding intermittent fasting while maintaining the same calorie intake.
I've done both. I can attest that intermittent fasting, at least for me, is WAY more sustainable ... and actually makes maintaining a calorie deficit easier too.
Hunger is a weird thing. People tend to assume that if you don't eat you'll just get hungrier and hungrier. The reality is that hunger comes in waves. If you can ride out a wave of hunger for 30 - 45 minutes it goes away. And the longer you don't eat, the less hungrier you get. I think this is because those waves of hunger tend to correspond to your eating habits. So if you're accustomed to eating lunch, you feel hungry around lunch time etc.
After a period of adaptation, when this just becomes the new normal, you can find that when it comes time to eat you just don't want to eat all that much either. It's weird, but cool, and seems to work well for a lot of people.
Then there is metabolic adaptation, which is thought to be the biggest contributor to people re-gaining any weight that they've lost. What happens is that after dropping around 10% of your body mass, your body kicks in a survival mechanism whereby it lowers your resting metabolic rate to adapt and try to slow the weight loss. This means that two people who weigh the exact same, one of which just dropped a bunch of weight to get there, will require different caloric intakes just to maintain their weight. The person who just cut weight will need 300 - 400 fewer calories per day than the person who didn't.
If you cut weight just by caloric restriction alone, this is DISASTROUS, because you are hungry and weak and miserable ... and you need to eat even less just to keep the weight off.
Which is why crash diets don't work. You start by making sacrifices, which is uncomfortable, and then when metabolic adaptation kicks in you stop seeing results unless you make even more sacrifices. People can't stick with it so they stop dieting and very quickly and easily regain the weight.
Intermittent fasting not only helps with hunger control, but there is research that suggests that it can also increase resting metabolic rate, which can help to counteract metabolic adaptation.
But even if it didn't boost RMR, the fact that it helps with hunger control and maintaining a calorie deficit alone would make it more sustainable for more people than just trying to eat less in general.
I'll add that intermittent fasting (16/8) has also conditioned my brain (and stomach likely) to eat less during the non-fasting window. In 6 months I'm down 20 pounds (198 to 178), I've also removed alcohol consumption except for in-person social events. My main concerns with 16/8 are:
1. I drink coffee in the morning, it helps with hunger, but im also wondering if this will have long-term affect to my stomach
2. I'm losing weight, but I'm wondering what to do to stop losing it, I'll soon reach a healthy level.
3. It gets annoying being told 'you shouldnt skip the most important meal of the day' by people all the time.
I've been doing IF consistently for about a decade. I never needed to lose weight, I did it to improve my healthspan. This is just my experience so obviously YMMV
1) I drink coffee in the morning too. No stomach problems yet, but I'm completely dependent on caffeine. Last summer I did a 4 month hiatus from caffeine and at the end I determined the tradeoff for me wasn't worth it. The energy and focus is just too valuable, to go without.
2) If it's going well, I wouldn't worry about it. At some point your body will stop having a huge fat reserve to burn off, and you will find that your energy levels crater and recover very slowly if you exert yourself too much for a given macro load.
3) You should try an extended fast! My response to "you are skipping the most important meal of the day" is "I don't even eat every day, fasting is good for you". If they press the issue I'll tell them about fasting for 5 days and how good it makes me feel.
And extended fasts really do make me feel amazing after the fact.
The more that one experiments with these diet changes, I think, the more one reveals how untrue that phrase "most important meal of the day" becomes. I feel unstoppable if I skip breakfast, lethargic if I don't.
I'd like to see a RCT that compared two time-restricted eating groups: 7am to 3pm, and noon to 8pm. Which would have the larger benefit over a control group?
Also, it would be good to simultaneously (somehow) check if the results depend on one's genetic or cultural bias towards eating in the morning or evening.
It most definitely is highly personal, like most weight management advice seems to be.
The only immutable truth is that calorie deficit will make you lose weight.
BUT different people find different methods of calorie deficit easier to handle mentally and/or physically.[1]
I can easily go even 20 hours without food maybe only sipping on some water or tea, my grandmother is the same. She can just have a big meal once per day and go about her day (and night) just fine.
My partner on the other hand needs to eat every 3-4 hours or they become completely unbearable mentally. It doesn't need to be a full meal, but some kind of calorie top-up is essential.
[1] ...and it seems that different people get different amounts of calories from the same food, it's a gut flora thing.
Probably depends a lot on what (and how much) you eat for breakfast too?
If I don't have some kind of protein in the AM, I quickly start having mental/emotional issues (and end up with recovery problems due to exercise, including pain). Trying to make up for it at lunch is a losing battle.
Just an anecdote, but for a few years I always skipped breakfast and had black coffee, and I did eventually develop some pretty severe heart burn issues. I went to tea for a while, back on coffee but usually eating breakfast again. I guess I’d just keep an eye on it and take action before it gets extremely painful, I’m not sure it’s guaranteed or anything.
Yeah I agree it makes it easier to eat less calories, and it's a simple rule to follow.
Sometimes I might count calories also, but if I just eat within the window it is unlikely I'll go over.
However, one unforseen side effect for me is that I sleep better on an empty stomach and feel better when I wake.
Years ago I did some experimenting on myself, including increasing to gain weight, and at least for me hunger seems to mostly be a function of relative emptiness from recent maximum fullness.
Sounds odd, but let's say I filled my stomach to 90% of my total capacity, then a few hours later I've digested down to 45% capacity and that's when I get hungry. That's -50% of the last maximum. If I spend a week or two restricting what I ate to a maximum of 60% capacity, I'd only get hungry around 30%, also -50%. But with less total calories eaten.
(numbers made up just to give an idea what it felt like)
I do 24-48 hour fasts weekly and for me the single biggest determinate of hunger is what I ate the day before.
Carbs, especially sugar and processed carbs make the fast day’s miserable. But if I stick to meat, vegetables and some whole grains it’s usually no big deal.
> If you can ride out a wave of hunger for 30 - 45 minutes it goes away.
I read "the glucose revolution" and it talked about reducing blood sugar spikes. If you have a big blood sugar spike, later you will have a blood sugar crash with a lack of energy, reduced concentration and... cravings.
I suspect that if you minimize your blood sugar spikes, you will reduce the crash later and waves of hunger aren't as much of an issue.
> If you can ride out a wave of hunger for 30 - 45 minutes it goes away.
I don't know how scientific this is but this comes from a person I consider smart & knowledgeable:
My medical doctor friend explained this as hunger being triggered by a nerve signal from your stomach that food in your stomach _is about to run out_. That is, once it runs out, the nerve signal goes away.
Before starting intermittent fasting I decided to try out a 24 hour fast, just to see how it would feel, and I felt abysmal and ravenous by the end. But after eventually starting intermittent fasting (which I ended up doing for at least 3-4 years), I had a few times where I would casually fast for nearly two days just by skipping my window one day, and it was not especially difficult.
Our bodies are so absurdly adaptive to just about anything we can throw at them. And so it makes sense, in some weird way, that if you're going to do something - doing it to an extreme degree can make things easier than going half way, since you optimize for the adaptive response from your body.
I've heard from many people who have had success with IF that somewhat more aggressive schedules (e.g. 20-4 compared to 16-8) can be easier to maintain.
I think it's just going to vary a lot by person. I tried a 12-8 fast which basically just meant skipping breakfast which seemed like a gentle intro. A few weeks in and I was so painfully hungry at times I was noticeably irritable and having trouble waking up. Also, didn't lose a single ounce.
I've not really tried fasting, at least not deliberately. I do notice that the times I get hungry differ depending on whether I'm at home or at work. Expectation of when you are going to eat does seem to factor into it somehow.
> After a period of adaptation, when this just becomes the new normal
Yep, and eventually even hunger you do feel is easy to ignore. I practice TRT and was meeting a friend at 3pm for a late lunch. I just skipped food all day, ate a nice meal at 3pm and then a very light dinner. Wasn't ever hungry after working out and working up until that point.
Agreed. My mom was complaining that she had a blood test scheduled for noon where she had to fast before the test. I was confused as to what she was upset about, and then finally realized that she didn't think she would be able to fast until noon. I'd been doing IF for so many years that this problem didn't even occur to me. Like, you can't go until noon without eating? :-)
Bingo. This is pretty much exactly what I found to be true after many years of failing to lose weight - then adding IF/TRF to the party - it made it a lot easier.
It's also psychologically easier to manage. People have an easier time building a schedule where they do or don't eat and holding it (say, by skipping breakfast) than they do managing counting calories around things like "I went out to dinner and probably ate too much".
Binary choices (should I eat right now?) take much less cognitive overhead than spectral choices (What should I eat? How much of it? If I eat X and Y now will I have the capacity to eat Z later?)
The incredible thing is you don't really need to count calories, you just have to avoid complete garbage.
As Michael Pollan says "Eat food, mostly greens, not too much".
Don't eat anything processed, don't eat anything with more than one ingredient and only eat meat with at most one meal, and ideally quite a small portion.
Completely and utterly ignore things like icecream, chocolate, soda, candy, chips, anything deep friend and other "non food items". Treat them like Arsenic - i.e. you should never eat them.
There, you are now restricting calorie intake and you didn't have to count anything.
Out of all the advice in these comments, this contradicts the scientific evidence on fitness and nutrition the most. Everyone should do the thing that makes it the easiest for them to attain their health and fitness goals. Living an an acetic life because an internet comment and Michael Pollan said so will work sustainably for very few people.
Adherence/consistency is the single most important factor to consider when building a fitness plan. Evidence shows users of systematic plans like weight watchers points are less likely to lapse in the long term. A very gradual improvement that works for a long time is much better than a deep “improvement” you practice for 1.5 months before giving up.
I’d much rather count calories and eat ice cream every day than treat ice cream as arsenic. For me a little bit of a treat every day makes self control around my diet easier overall - I never buy snacks or overeat at meals because I think “hrrng if I spend this calorie now, I cant spend it on ice cream tonight”. Might not work for everyone - there’s a lot of commenters here who prefer TRE because it’s easier for them; if works well that’s what they should do.
If living an acetic life without treats works the best for you, then do that - but don’t tell other people they should do it too.
There’s no reason to fear treats if you can manage them; if time restricted eating or calorie counting enables someone to eat the food they like, and so life is more enjoyable and it’s easier to adhere to a good diet, they should do that.
> you just have to avoid complete garbage. As Michael Pollan says
That reminds me of something I saw a long time ago:
> Fuzzy Pink Niven's Law: Never waste calories. [...] Don't eat soggy potato chips. Or cheap candy. Or an inferior hot fudge sundae. Or a cold soggy pizza.
What humans consider food has changed more in the last 100 years than it did in the preceding 10,000. Eat what your great-great grandmother would consider food, not what a scientist in a lab is trying to sell you as food.
Cake, donuts, ice cream, etc derive their extreme calorie density and negative satiety from cream, sugar, and frying, not some recent invention by a "scientist in a lab".
It's not hard in the sense that solving complicated math problems is hard, but hard in that it adds a non-trivial amount of effort to an activity you do multiple times a day, every day, in perpetuity.
Even the small effort of measuring your creamer with a teaspoon instead of just pouring it in the cup just takes more time and effort than simply checking what time it is.
This is not really true. Generally speaking, at the grossest level of averaging, regularly eating 2 meals instead of 3 or 1 meal instead of 2 results in a long term net reduction of calories.
Additionally your stomach shrinks under this regime - that one meal will definitely make you feel full and satiated.
All this goes into ease of adherence - I just don't have to think about it. I eat as much as I want for dinner each day and have dropped a steady 10lb/year for the last 5 years.
And the actual title of the study is 'Effect of Time-Restricted Eating on Weight Loss' which describes a concept that is basically the colloquial definition of intermittent fasting.
The popular term 'intermittent fasting' usually describes time restricted eating, with a fasting period usually between 16-20 hours.
Sorry, no. Whether it was always the definition or not, having a daily window to eat that is generally much shorter than normal is called intermittent fasting.
Except for those people who wake up and have a midnight snack.
Cutting out the snacking is probably also a major factor in the effectiveness of intermittent fasting, especially given that snack foods are often more processed, calorie-dense, and less nutritionally balanced than what we typically eat at meals.
I think a lot of people could lose significant weight by simply eating three meals a day at the usual times, but just cutting out snacking between meals entirely and changing nothing else. Just fasting between meals, if you will.
Good observation! Fasting in general is usually at minimum 8 hours, which is also around the time we sleep. There seems to be some evidence that the longer one fasts, the better the benefits. You would be surprised how many people in the US eat right up until they go to bed, and then eat breakfast right after waking up. So for some, extending the fast 2-5 hours is no small feat.
I see this kind of 'well actually' style response a lot when calorie counting vs intermittent fasting gets brought up. Yes they're both forms of calorie restriction in general but the mechanism and the ease of adherence is pretty difference so important to study especially given the results that IF seems to be significantly more effective because it's easier to execute.
After causally seeing popular weight loss advice in US media over the years offering all variety of silver bullets (One Weird Trick etc), I was flabbergasted and betrayed to learn how simple the math of weight loss is once I finally looked into it 4 months ago.
Very roughly, there’s 3500kcal in 1lb of body. Given that fact plus your current weight and calorie intake, you can build a spreadsheet in 30 mins to compute the calories per day to make your body any weight you want in a reasonable time frame (losing >1% a week is generally viewed as unhealthy and risky).
Of course adhering to the plan is the challenging part - and then it’s helpful to consider strategies like TRE, once you understand the metric target part.
I wrote the comment as a reaction to the editorialized headline suggesting to some degree that TRE is a silver bullet / One Weird Trick. Maybe it is effectively that for many people - but in case there’s a casual reader scrolling past I want to give them a bit more of the ground truth that’s somehow not popular knowledge.
> Very roughly, there’s 3500kcal in 1lb of body. Given that fact plus your current weight and calorie intake, you can build a spreadsheet in 30 mins to compute the calories per day to make your body any weight you want in a reasonable time frame
emphasis on the very roughly ... a significant part of body mass is tissue you do not want to lose: bone, brain, organs
1lb of fat is ~3500 calories and that is simply 9 calories per gram of fat X 453 grams in a pound. its actually closer to 4000 but people just use 3500 because that means you would need a 500 calorie deficit per day to lose a pound a week.
That doesn't strike me as "well actually". The title says "more effective than calorie restriction". If it's a form of calorie restriction, then the title doesn't make sense: "Form A of calorie restriction is more effective than calorie restriction".
I think a clearer title would be something to the effect of "Intermittent fasting more effective than calorie counting for calorie restriction"
Also worth pointing out that the study was specific to T2 diabetes.
Nothing really works that well for most people ,and there is a lot of ambiguity. I am thankfull we have GLP-1 drugs , which unlike having to compare CR vs IF, seems to work for most people .
I’ve been IF for a while now, and it’s the easiest approach to “putting down the fork.” Rather than continuing on a standard eating schedule, simply skipping a meal or going longer between eating actually creates a new habit rather than trying to modify a bad one.
I’m actually capable of going an entire day without eating now and I’m not craving anything. A lot of days I’ll only have one meal, sometimes two.
It’s done wonders for my health. I’ve lost a little under a point per week (wouldn’t recommend more than this), my blood pressure is down, I no longer get heartburn after eating anything, and I feel lighter and healthier.
There are also tons of studies indicating that going longer between meals is healthier, and had anti aging effects on a cellular level. Seems to be an all around winner to me.
if you have a 'daily budget' of 1500 calories, personally I would much rather skip breakfast and have a burger and fries for dinner than 3 'slim meals' throughout the day (i'd probably stick to that more readily too)
Adherence is all about psychology! Although what works for one person might not work for another as well; if time restricted eating or calorie counting doesn’t work for you, try a different strategy.
My target right now is 1600 kcal & 150g protein, and my usual meal plan is a 300kcal protein frappe coffee thing in the morning, a lunch around 450kcal like gumbo, a 550kcal dinner like apricot glazed salmon w/ couscous, and then ~300kcal of Ben & Jerrie’s ice cream for dessert. For me adherence is super easy because those are all foods I love to eat, I’m full all day so I never want to snack, and I’m actually eating more dessert than before this diet because I don’t feel guilty about it anymore (yay decadence).
My girlfriend tried the same plan, but something about just knowing about the budget makes her feel totally trapped and she ends up binge eating snacks almost out of “revenge” after a few days. ¯\_(ツ)_/¯
I skipped breakfast for years because I was too lazy to make it. Then I ate fast food and pizza all the time and I still got fat. You're not gonna lose weight just skipping a meal.
While dietary adherence might be easier with that eating schedule, it isn't optimal from a protein metabolism standpoint. With any calorie restricted diet you risk losing lean muscle along with fat so you need to get enough protein to mitigate that (along with certain types of exercise and other factors). And that protein should to be split across at least two separate meals in order for your digestive system to process it effectively.
I don't believe it's as simple as what's the net -ve because with TRE the BMR (Basal Metabolic Rate) does not reduce like with calorie restricted eating, so the net -ve is higher with TRE even when the calorie intake is the same. Also, reducing the BMR has other negative effects because the body does away with key repairing processes to live with the reduced availability of energy.
I think at reasonable sustainable fitness planning & weight change goals the BMR changes aren’t a significant factor. My target is to lose about 0.9% body weight per week. I did some napkin math numbers before starting my plan and decided not to worry about it much, and in my case seem to be fine.
I went from somewhere around 2400kcal daily to 1600kcal daily while eating 3 meals and lifting for 30min a day and my estimated resting energy expenditure per day by Withings & Apple Health is down about 60kcal over ~4 months. They’re not super accurate sources, but at current rates I’ll hit my target minimum weight before my estimated resting expenditure has dropped -100kcal.
Everyone's different. I did IF for 6 months and lost to the point of being gaunt, so I had to stop. It seems to have changed my metabolism for the better, because now I can eat what I want (mostly pizza and ice cream) without gaining weight. Of course, I don't overeat, or I would gain weight.
Intermittent fasting doesn't suddenly change the laws of thermodynamics. Of course if you still eat 2,500 calories a day you will likely gain weight unless you already have a lot of muscle (but if you do, you likely know what you're doing enough that you're not reading this article actually hoping to learn anything).
The point is that IF makes it easier to reduce calories, in part psychologically but also in part because it's just a lot harder to eat 3,000 calories in 4 hours than it is to eat 3,000 calories in 12 hours.
Yeah this is what people often forget. In the end it comes down to calories in vs. out. Unless IF revs up metabolism in some way, which the evidence suggests it does not. No free lunch, sorry.
The problem with your thinking is that you assume that your eating habits don't effect your energy consumption. But that is wrong, if your Blood Sugar is to high your Body can't access Fat and needs to Burn other sources that are scarce and it prefers to make you tired and cold to reduce energy consumption. That doesn't happen if your Blood Sugar is very low and you can easily access your Fat reserves. Eating spikes your Blood Glucose, that's why intermittend fasting works so great.
I've (unintentionally) done intermittent fasting for most of my adult life. Frankly, it's just mindless. I don't have to think about it that hard. When I did keto or calorie counting years prior it was basically not only part of my day but part of my life.
I looked briefly into this and it seems that while there is evidence that intermittent fasting may be useful in preventing cancer and may be useful as an adjunct cancer treatment (in addition to chemotherapy and/or other treatments), the effect is largely from weight loss, not other mechanisms. Review article here: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9530862/
From the conclusion:
"There is presently little evidence that intermittent fasting, without any reduction in body weight and proper balanced diet and exercise, can enhance cancer outcomes."
So, while the details in this review are interesting, the conclusions seem to come down to basic health advice: maintain a healthy weight, eat a healthy diet, and get exercise. Seems like good advice for pretty much everyone.
The only challenge of intermittent fasting for the masses if anyone happens to need to take medication in the morning that requires some food. Moving the eating window isn't always ideal.
The problem with most diet/fitness advice is that it comes from fit+healthy people who've never had serious weight/health problems, and for whom it's all easy.
Appreciate you stepping out to engage in this. I’m going to answer this in support of the perspective you’re speaking from.
There is advice available from people who haven’t always been healthy and fit, but are now.
Should someone seeking diet/fitness advice take it from someone who hasn’t become and remained reasonably fit or diet?
One thing for me I strive towards is remembering building discipline is one of the key if not the master habit that unlocks so many other ones. For me a responsible mindset empowers, and a victim or blame mindset disempowers and I try not to forget it.
Longevity whether I like it or not is based on two things, a bit (not a lot) of regular exercise where uninterrupted walking over 60-90 minutes is amazing, and reducing the amount of processed food and step by step making sure the diet is one that best suits each individuals body. Reducing a harmful activity is a great start instead of making big leaps.
I have folks with weight and health problems in my life.
It’s easier sometimes to think it’s easy for people who have it done, but not know their story
Starting and keeping going 1% better every day is the way and something everyone can learn to do relative to themselves as long as they don’t compare, and don’t stop. Intermittent fasting (starting with a smaller window and increasing it by 5 minutes every day than normal can be very helpful).
For an example that isn't from such people, there is always The Hacker's Diet[1]. I'm not nearly type-A enough for it to work with me, but at least it's from someone who struggled with weight.
I have been doing intermittent fasting combined with increased cardio activity, significantly reducing sugar intake (only source is from fruits and occasional/once a month indulgences) , and mild increase in fish consumption while reducing beef consumption.
So far, 20 lb weight loss in 3-4 month period. Cholesterol levels were “borderline” prior to weight loss (no statins Rx’d). Fasting glucose normal.
Anecdotally, reducing intake works!
side note: the sugar addiction was real and “retraining” my body and mind was the real effort. The mental fortitude to ignore the usual junk I grab at the grocery store is well understated.
I increased my sugar intake by 1/2 tbsp brown sugar in the morning and about a fifth of a pint (300kcal) of Ben and Jerry’s ice cream every night, I eat 3 meals a day up from 2, and also lost 20 lbs in 4 months!
At the end of the day, it’s all about the numbers — my intake is 1600kcal, and estimated expenditure is 2240kcal – and whatever makes it easy to stick to the plan. For me it’s ice cream.
Yes, that is the energy content of the food you eat. Your body still has to metabolize it, store it, and use it. There are sometimes extreme variations on how that takes place between individuals.
Exactly this. There's still a ton of study needed on gut flora and other mechanisms of metabolising calories.
Some people (like me) will almost literally get fat just by walking past the candy isle in the store, my body will suck up every single Joule of energy from any food I ingest.
Meanwhile I have a friend who was actually prescribed by a doctor to eat more fat (butter, specifically) every day because they just don't hold on to calories _at_all_. Everything goes straight through. He's been stick thin for the 25 years I've known him, no matter what he eats and how and when.
Eating ice cream almost every day helps my self control a bunch. I serve into a little glass bowl on top of my kitchen scale to my target mass, and whatever’s left in the tub I put away knowing I’ll get to have it tomorrow or later this week.
Black licorice is a terrible vice for me because it seems like less of one. I do OMAD + hiking + zero alcohol, and lost about 20lbs in 3mos as well. I've done omad before, but was sedantary and still drinking and while it worked, I gained it all back when I started adding lunches again, but it was because of being sedantary.
OMAD is effectively calorie restriction anyway because the longer you do intermittant fasting, the lower your average calorie consumption becomes over that period. Can't say it's healthy or smart, but it worked for me.
Current play is adapting this OMAD + hiking + zero alcohol for the winter to be fewer hikes but adding stronglifts 5x5 3-4x a week as a routine, which should consume any marginal meals and create the metabolic demand as I start lifting heavier again. I've found that sobriety is a free super power as well, can't recommend it highly enough for cutting out impaired judgment snacks.
In my experience and observations, calorie restricted diets are pretty easy to adhere to until sometime between dinner and bed time. This is where people typically go off the rails and eat far in excess of satiation, negating any success of the day.
Intermittent fasting typically has people shift their eating times towards the end of the day which should significantly reduce the chances of falling into a pre-bedtime eating habit. Especially if you also shift your sleep window earlier. So if you stop eating at 8PM and make sure you're asleep by 10PM, you're less likely to get hunger pangs.
I once heard a great tip to prevent those pre-bedtime snacks. After dinner, brush your teeth as if you’re going to bed. Your brain already associates that with “no more food” and so programmatically dissuades you from eating. It’s always worked for me.
I lost a lot of weight on a calorie restricted diet, from 215lb to 165lb over the course of a few years. But I gave it up because counting calories is soul sucking. I much prefer things like intermittent fasting or keto, I can think about what I am eating less and it's really raised my quality of life.
> But I gave it up because counting calories is soul sucking.
In the beginning it certainly is. But once I did it for a while, I found that I had developed a mental understanding for what various foods represented in terms of calories and could navigate it with much less effort. I started with spreadsheets and apps.
IMO much of the value in calorie counting stems from those early weeks where you suddenly realize how many calories each food represents - and relative to that how filling you find them.
It wasn't so bad for me when I started in college. Everything was prepared in the cafe and had calorie count on it. When I graduated and got married we started making all our own food and that was when it became depressing for me.
I'm glad this works for you but this is far from a universal solution. It's true that thirst is often mistaken for hunger and in those cases this can work.
Personally when I wake up I quickly need a meal – I always drink a glass of water in the morning and it does very little, but if I have a black coffee the caffeine gets rid of my hunger for a few hours.
It makes you wonder if the intermittent fasting made the participants more aware of when they were actually hungry vs eating mainly out of habit/boredom/coping mechanism.
If I follow an overly strict diet, I wind up thinking about food all of the time. Calorie counting is a form of strictness: I'm continually putting in more time thinking about food. How many calories was that? Do I need to log everything? Do I figure it out when I'm planning and add the extra food thought time there?
And so on.
I've only lost weight through specific dietary changes that are easy to follow. Usually, this has been things like changing daytime food to something more healthy or fewer calories. Or simply putting more vegetables in my diet. I'm currently pescetarian, but rarely eat fish.
Intermittent fasting is in this second category. There isn't much to keep track of and I wouldn't have to put all that much extra thought into it. Some folks could put little to no thought into it. It makes it easier than anything strict.
The intermittent fasting group adhered to the prescribed eating interval 6.1 days per week. In the calorie restriction group, 68 percent achieved the calorie reduction target over six months. The intermittent fasting group lost more weight, reducing body weight by an average of 3.56 percent in six months, which was significant. Under calorie restriction, body weight fell by an average of 1.78 percent, which was not significant.
You should change the title to more accurately reflect that. The first question someone has when reading that title is "effective at what?" and there's room in the title for it to say so without the reader having to click through.
Appreciate that, however people use I.F theorising that it helps all sorts of things, insulin sensitivity, lifespan, inflammation markers etc, not just weight.
My tldr: intermittent fasting is easier to adhere to than calorie restriction.
Or in plain English: it’s easier to get someone to eat less by getting them to limit windows in which they eat than to ask them to eat less and keep the same routine.
Tre = intermittent fasting
Cr = calorie restriction
The TRE group reported being adherent with their eating window a mean (SD) of 6.1 (0.8) days per week (87% of days) over 6 months (eFigure 2 in Supplement 2). In the CR group, 17 participants (68%) reported being adherent with their prescribed calorie goals during the 6-month trial (eFigure 2 in Supplement 2). Participants in the TRE group reported finding their diet intervention easier to adhere to compared with CR group participants (eFigure 3 in Supplement 2
The most recent critiques I've seen for intermittent fasting have to do with how it may not preserve lean body mass unless you are extremely conscientious about getting enough protein (and probably resistance training). That is, if you don't get enough protein during your feeding windows, you'll lose lean body mass along with fat mass, which harms body composition. I'd expect to see the TRE arm losing more lean body mass.
Table 2 seems to show this effect. The TRE arm lost more lean body mass and fat mass, although without a difference in visceral fat. If compliance is the issue, I'd be curious to understand what regime can help TRE participants comply with a minimum protein threshold in their diet to minimize the risk of lean body mass loss.
Different intermittent fasting regimens result in different results re: losing lean muscle. The longer intermittent fasting cycles seem to show no significant loss of lean muscle. (i'm way too lazy to go find the studies to back this up claim, but they're out there somewhere)
> The longer intermittent fasting cycles seem to show no significant loss of lean muscle. (i'm way too lazy to go find the studies to back this up claim, but they're out there somewhere)
"Absolute" means "unquestionable, fundamental, ultimate, no exception", etc. You've linked to a single study which did not test all forms of IF. You can't say you know something absolutely if you haven't even tested for it.
Specifically, there are much longer periods of fasting which may have a different impact on the result which are not tested for here. There is a claim about alternate-day fasting which is actually not supported in the linked study.
In addition, the longer alternate-day fasting practices may include ad libitum which may have a detrimental effect. Lack of adequate protein is presumed by many to be linked to loss of lean muscle, and the quality and form of feeding during feeding windows would therefore be of high importance, but doesn't seem to be accounted for in these studies.
An old fashioned way of fasting preserves muscle mass way better due to hormonal response. It only kicks in after 30-40 hours of fasting. I don’t think that a lot if people practice 3-4 of fasting when doing IF.
To be fair, any substantial calorie restriction TRE or not means you will lose some muscle/lean mass. I’m not sure table 2 shows evidence that TRE is more detrimental to lean mass than CR given that the TRE group had fewer calories on average than the CR group.
It’s possible to minimize the loss by consuming large amounts of protein, but some amount of it will be converted to glucose unfortunately. The difference is very drastic, you can preserve a lot of muscle mass by doing proper diet vs IF. It all adds up when you so it for 6 months.
Latest I've heard is that it all boils down to calories and that intermittent fasting (time restricted eating or 8/16)makes you lose muscle faster due to low protein during the fasting period.
Better to eat less calories and consume small amounts of protein throughout the day.
I tried IF a couple times in my life. First time, coupled with lots of endurance exercise, worked great but I was constantly fighting to retain muscle. Second time I didn't exercise as much but also didn't lose any weight. I did develop extreme post-meal fatigue though, and that has persisted for years since stopping IF.
The body doesn't store protein in any real capacity. Fat is stored in adipose tissue and carbs in glycogen, but protein must be available in the bloodstream when needed for muscle maintenance and synthesis.
Even if you up your dietary protein during the feeding window, if you're fasting for lengthy periods of time where the protein has already been utilized for fuel, then the muscles are starved and catabolic. There's no passive protein depot built into our physiology muscles can pull from.
Is it possible some of the area it uses protein from is old cells? I'm thinking parts of digestive system, immune system, old cells it scrubs and reclaims some protein from when fasting. Still catabolic but useful catabolic?
It is called autophagy and happens regularly in our body, but in very small amount. Do experiece greater results, you need prolonged fasting (3-5 days)
After reading Benjamin Bikman’s book (Why we Get Sick) I think the other benefit of IF/TRF besides caloric restriction is that you’re also reducing your “insulin abuse”, I.e you are avoiding having elevated insulin levels for a longer period, which helps with improving insulin sensitivity. This book (highly, highly recommend) makes the case that insulin resistance is at the root of many metabolic and other disorders. I think there’s too much focus on weight loss in these threads, but even those with normal weight and BMI can have issues due to insulin resistance.
> Leptin’s main function is to help regulate the long-term balance between your body’s food intake and energy use (expenditure). Leptin helps inhibit (prevent) hunger and regulate energy balance so that your body doesn’t trigger a hunger response when it doesn’t need energy (calories).
As far as I'm aware. Eating less for a longer time and you're body will reduce energy expenditure and etc..
PS. If you want to lose weight, you want your energy expenditure to be as high as possible ;)
PS2. Not an expert. Read a lot about it and this seemed to theory seemed to fit my practical experience with losing weight ( -25 kg. in about 6 months. | from > 100 kg to ~ 77kg )
>> PS. If you want to lose weight, you want your energy expenditure to be as high as possible ;)
How do you deal with the hunger resulting from high energy expenditure. I find myself famished after a tough workout (interval training / strength training).
I realize there are other benefits to interval training / strength training (e.g., endurance, toning, increasing mass), but I wonder if it runs counter to weight loss given how much hunger it induces.
Based on personal experience here. You're doing HITT? It's possible for a short intensive workout ( under 25 minutes) that you're body isn't taking from fat, but trying to get it from food you ingested. That's why it's "suggested" to do lower intensity workouts.
If you do heavy training, you can eat more than you did before too.
Also a lack of vitamins could create cravings ( eg. Because of a lack of sunlight/sleep), you need more vitamins since you workout more.
Losing weight is 60-70% eating correctly, the rest is exercise.
I'm still inclined to believe that gaining muscle is the best way to go for losing weight/fat as a male.
If you do weights:
Don't measure you're weight every day ( muscle is heavier than fat), if you want to check that, do it weekly ( preferably with a fat % counter. Same time of day, same water intake. Since it works based on conductivity / water. Water intake can change results slightly). Try the mirror instead.
Building muscle is slow, but losing muscle is slow too... ( Less strict "diet", useful for holidays)
Cardio is fast, gaining it again is fast too.
Ps. If you're always hungry, I think you're going to extreme and you're body is starving versus the exercise you're doing.
Note: random thoughts. Feel free to give some feedback so I understand the situation a bit better.
Fyi. I'm not considered an expert on the topic. I read a lot + personal experience and experimenting. You're mileage may vary ;)
It's not, but the title is extremely misleading. You MUST be in a calorie deficit to lose weight. What the study shows is that simply by doing intermittent fasting, people naturally tend to eat fewer total calories per day, and can end up in a caloric deficit.
Please people, do not simply think that intermittent fasting makes you lose weight. If you still have a propensity to eat junk food or just a lot of food even in fasting windows, you could still be gaining weight or staying at maintenance.
Personal take here -- I try to time-restrict eating. I'll brush my teeth right after dinner and essentially close off eating. Git commit. Git push. Done.
The nice thing about this is how it prevents snacking at night because you're in an "off" state that is binary. I cant trick myself into thinking a tiny bit will be OK, because any tiny bit wrecks the binary state of fasting.
Good to note it's not impossible to be in a calorie deficit and not lose weight. Lipedema for instance makes it impossible to lose fat on the legs and arms. Hard to get a diagnostic for it too. Other than that your comment is right, you can also not lose weight when doing IF, it's all about calories in calories out.
Hate to be that guy because I know what you were trying to say, but not really, not necessarily. You can avoid eating for the first X hours of the day and then gorge yourself on a huge meal and be in a caloric surplus at the end of the day.
While your point is valid, the researchers in the paper cite evidence from other studies that intermediate fasting reduces calorie intake.
I think the OP has a pretty reasonable point, intermediate fasting, restricts calories to certain hours, calories restriction in general restricts calories to a quantity.
Probably worth exploring the citation to know how well this holds.
“Evidence shows that limiting the eating window to 6 to 10 hours within a 24-hour period naturally reduces energy intake by 200 to 500 kcal/d”.
(There are zero studies that show that time restricted eating causes a greater weight loss effect compared to other eating plans when calorie deficit is equated between the groups)
As someone who has been doing, IF for 11 years and has moved to OMAD (more or less) I’d say…not really
Yeah, you might gorge yourself on occasion and have one our two day surplus, but it’s not something that anyone would regularly do because it’s not only uncomfortable, but it also messes with your gut. So in function while you’re correct, it is possible theoretically to ingest the same calories in a tiny window of eating as somebody who eats throughout a whole day, your body can’t process food that quickly and will give you significant gastrointestinal distress
OMAD it will always be pretty hard to eat a lot. But, for slightly more accommodating feeding windows, people can still eat plenty especially if they have higher density foods
I restrict myself to a 4 hour eating window, and vary that window daily based on what's convenient to me. So some days I'll go 24 hours between windows if that's how things line up.
There are a bunch of advantages for me. I have 3 kids and I always start my window after 10am. Without the restriction I'll end up finishing off their breakfasts and snacking when I'm making their school lunches. Or late at night it's easy to resist the temptation of hot milk and cookies as it's outside of the window.
By myself I'm actually a pretty disciplined eater, but with kids and a partner who is a chronic feeder I need the window as a barrier against lazy eating.
If you're a diabetic like me I'd recommend don't do intermittent fasting. I almost died. My blood sugar goes from 300+ to 50ish some days and when I tried this I never felt hunger. I felt like I was about to slip in a coma all day.
Imo it's still hard to stick to after a while. You're out with friends and want to eat/drink, or you get depressed and want to eat/drink during your fasting window, or you end up eating later than you should due to the time window. I've been struggling with keeping on track lately because I don't have a goal I'm working towards to keep me accountable. I lost a bunch of weight, but then had no real reason to keep it off other than "for health", and now the weight's coming back.
Interesting to know that you don't need to become a dull and boring person without social live if you want to do TRE :-)
The interesting bit for me: "Participants in the TRE group were adherent with their eating window on a mean (SD) of 6.1 (0.8) days per week"
I like TRE, but I don't follow it religiously. Some day of the week I will drink a wine with my partner or drink a beer with my friends. The night I drink I also eat a breakfast the morning after. Nice to know that it works if sometimes you fail to follow.
People also have some luck on other diets by having a "cheat day" one day every week or so.
I mean, eating well 85% of the time is better than not doing it at all and most folks will still run an overall calorie deficit. And for a lot of people, if they can make 75-85% of their food decently healthy, they'll be better off.
I'm a cyclist that rides anywhere between 200 and 500 Km a week (depending on the season) and does IF 20-4 from monday to friday. I usually eat after work at 4 PM.
You can absolutely do low intensity workouts in a fasted state and I regularly do so after work. In fact it helps burning fat reserves. Just don't overdo it.
On weekends, when I do my longer and/or more intensive rides I make sure to fuel properly though. I simply ignore fasting on those proper cycling days.
I tried 15h fasting (8pm-11am). It was fairly easy to maintain but it absolutely killed my ability to focus and concentrate while working from home. Then one day I had a nice breakfast and it was like night and day.
Tangential, are there benefits not caused by calorie restriction? I was convinced my body was repairing itself while fasting, and that my body generates no extra hunger pangs.
intermittent fasting always leads to calorie restriction in the mid and long run. due to secondary effects like increased insulin sensitivity, less time to eat, more conscious relationship towards food, different food preferences etc.
> Interventions: Participants were randomized to 1 of 3 groups: 8-hour TRE (eating 12 to 8 pm only, without calorie counting), CR (25% energy restriction daily), or control.
>In this RCT, a prescription of TRE did not result in weight loss when compared with a control prescription of 3 meals per day. Time-restricted eating did not change any relevant metabolic markers. Finally, there was a decrease in ALM in the TRE group compared with CMT. Together, the results of this study (1) do not support the efficacy of TRE for weight loss, (2) highlight the importance of control interventions, and (3) offer caution about the potential effects of TRE on ALM. Future studies should be aimed at understanding the effects of early vs late TRE and protein intake or timing as a means to offset the loss in ALM.
ALM = Appendicular (i.e., limb) Lean Mass.
One of the authors of this study, Ethan Weiss, is a cardiologist and was a big proponent of TRE, but after the results of his own study came in showing drastic loss of LBM in TRE group (to the point that most of the weight lost was LBM) and no added benefit, he completely stopped doing TRE, stopped recommending it, and went to Twitter and the news media to publicize the harm, eg: https://www.insider.com/new-research-finds-intermittent-fast...
>In the in-person cohort, the average weight loss in the TRE group was 1.70 kg. Of this, 1.10 kg (~ 65% wt lost) was lean mass; only 0.51 kg of weight lost was fat mass. Loss of lean mass during weight loss is normal but typically accounts for 20% to 30% of total weight loss
>So in summary: 1) no matter how you slice it, prescription of TRE is not a very effective weight loss strategy; 2) There was no advantage to TRE when compared to a proper control group; 3) What weight was lost looked to come more from muscle mass than fat mass
> The mean (SD) reduction in energy intake was -313 (509) kcal/d for TRE, -197 (426) kcal/d for CR, and -16 (439) kcal/d for controls
So — the time restricted eating group reduced calories more than the group that counted calories; but the resulting weight loss has the same cause: reduced calorie intake compared to before.
If there’s a take away here, it’s possibly that adherence to a calorie deficit using a time restricted eating plan is easier than adherence to the same calorie deficit by explicitly tracking calories.
If you can adhere to a calorie deficit through other means, you won’t lose weight faster by adding intermittent fasting while maintaining the same calorie intake.