> Time-restricted eating, in the absence of other interventions, is not more effective in weight loss than eating throughout the day.
I believe this, with two additions: In my experience, time restricted eating confers weight loss via reduced calorie intake (in short, if I only eat until I’m full for a 6 hour period in a day, I simply don’t eat as much).
The other factor is the supposed ‘cellular regeneration’ kinds of claims, along the lines of “well, if your cells arent metabolizing fresh food, they have time to do clean—up processes and this is good for reasons”. I would be interested to learn more along these lines, but it makes sense that this wouldn’t be directly related to weight loss as such and would instead affect other factors (longevity, gut and skin health, etc)
> (in short, if I only eat until I’m full for a 6 hour period in a day, I simply don’t eat as much)
Maybe for some people that will work, however as a food addict I can safely say that I can very easily consume more than a days worth of calories in a lot less than 6 hours. And have. A lot.
I am not surprised by the result. The only thing that really works for losing weight is CICO, and anything else is an abstraction.
I think the whole calories in / calories out phrasing is very disrespectful towards people with genetic obesity, (EDIT:) because these people can eat the same, sport the same, etc. as other people and still gain more weight. Telling them "just follow this equation like I do" hides the real problem behind a variable and is disrespectful because things aren't so simple for these people.
I am one of those people. I appreciate you saying this. I have spent decades of my life trying to lose weight including following doctors orders word for word for 10 years. It only ended with gained weight despite their beliefs in “physics”.
I am now 3.5 years into carbohydrate recovery and I’ve lost 200 pounds eating way way way more than my “TDEE”.
I’m not saying this for any other reason than to express my gratitude.
I lean toward either butter or tallow as a cooking oil, but outside of directly eating a stick I can’t imagine using an entire one to cook a meal per person.
It’s the phrasing, not the idea per se. Like, yes, weight loss is energy consumed - energy burned, but it’s rather obvious, rather unhelpful, and simplifies things in a way that triggers shame, not determination for people who have to overcome more barriers.
It’s like you’re in the middle of a marathon and someone running a 5k goes “have you considered running faster?”
I lost 30kg in a year or so by following "calories in / calories out". For me it was very helpful for two reasons:
1. Unlike a fixed diet or meal plan, it freed me to keep eating the things I wanted to eat. Not exactly as before, but to a large degree. I really enjoy my food, so not being forced to eat stuff I didn't want or like was crucial. Instead I focused finding ways of keeping the calories per day roughly at a target value. This simplified things a lot for me, as it was a clear and very tangible goal.
2. If I failed one day, say maybe I went out with some friends or I just had to have some ice cream or whatever, it allowed me to not feel bad about it. I knew this process would take a year at least, so "calories in / calories out" meant whatever I do today doesn't matter much, it's what I do every day that matters.
Imagine the time before the formalization of dyslexia within medicine. It would have been very disrespectful and cruel to tell people who found learning very challenging something like “just try harder! It’s basic physics, the more you study, the more you learn!”
No. The food you eat affects both sides of the equation. Different people will also have different responses to the same food due to factors like genetics, gut microbiome, etc. Calories in calories out works for everyone. Saying eat X calories per day to lose weight does not.
I agree. Neither you nor I made a specific comment in difficulty. Your parent comment stated it was disrespectful. I agreed and tried to use an analogy that would be considered both disrespectful and cruel by most people.
In addition, I have successfully eaten the “correct” amount of calories for years and years and still gained weight. I admit, andcdata, but I am not the only person with this story nor am I the only one with this odd medical outcome.
I put correct in quotes because it was ineffective. I did not lose weight eating the amount of calories that the doctors calculated. Is that surprising?
If you eat exactly 100g of refined sugar then your body can extract at most 400 calories. If you then burn 500, that 100 calorie difference must come from your body. That's all it means.
Finding how many calories your body needs right now to maintain weight is another issue entirely, and one which involves estimation and uncertainties.
If you find you're not losing weight while hitting your target value, well then it's simple[1]: your target value is wrong and needs to be lowered.
[1]: Assuming your doc verified you're not gaining weight due to water retention or similar.
Technically it is true... the same way as "atoms in, atoms out" is technically true. So why do people prefer saying "calories in, calories out" instead of "atoms in, atoms out"?
That's because "calories in, calories out" implies that there is an easy solution to being fat... you simply need to "out" more calories, while you "in" less calories, duh!
Which conveniently ignores all possible problems with trying to "in" less calories and "out" more of them. For example, that your metabolism can make you feel extremely tired, even pass out, if you don't "in" enough calories. Similarly, to "out" more calories you sometimes need more than sheer willpower; your muscles have to cooperate, and sometimes they will only if you "in" enough calories.
I mean anyone trying to tell you that it doesn't work and they have some magic shortcut for how to lose weight is lying to you. Their method for weight loss might work for you but not because CICO is wrong.
I would argue that CICO does not imply easy. The rendering equation really just says light in == light out but that doesn't mean writing a renderer is easy. People who say CICO doesn't work are usually trying to sell you an "easy" way to lose weight. Take this proprietary fat burning pill. Don't eat carbs. Don't eat fats. Eat 6 small meals a day. Eat 1 meal a day. Don't feed your mogwai after midnight.
If one of these strategies works for you, great. You've found a way to get calories in less than calories out.
One of those easy methods might actually work by affecting the "calories in". I mean, not everything you eat is processed by your body; some potential calories may be simply excreted. I can imagine how a pill, composition of food, or even the timing of it, might influence the gut flora, which in turn would change how many calories are actually extracted from the food.
This is the danger I see in simple slogans, that they make people automatically dismiss potential solutions. Of course, if a successful solution is found, it will be obvious in hindsight that CICO didn't actually contradict it. But no one who is happy with CICO as an answer is looking in that direction now.
EDIT: Same objection applies to "calories out". How do you spend calories? Typically by exercise or sport. But that way you can only spend calories that are currently stored in your muscles. What about calories that are currently stored in your fat cells -- how do you move them from there, into your muscles? Again, I imagine that a pill, or a change of diet, could make this more easy or difficult.
No, all calories are not the same. The basic process for measurements is "burn it, measure the energy output". " Burning" as in "gas flame, high heat, oxygenated atmosphere". This is something your body doesn't do, even if you supposedly "burn" calories. Your body uses different reactions that are often less efficient, meaning the energy output will be different from the calories measured. Nowadays some of those errors are corrected for, but not all of them. And depending on your personal metabolism, from genetics, daily changes and nutrient status, your body will be less or more efficient with some foods.
Irrelevant. If your body extracts only 50Cal from a 100Cal cube of sugar, but you counted that 100Cal value against your daily limit, then you're still achieving your goal. The problem is often that people set too high a limit and overestimate how much they burn during exercise.
Saying "all calories are the same" ignores a few really important things.
1) It ignores the processes involved in burning fats, sugars, and proteins, which can heavily impact where your body prioritizes getting its energy (or storing it).
2) It ignores other health impacts of 'calories' such as blood glucose levels, which absolutely will depend on what it is you're eating and not just the calorie count. Sugars, fats, and carbs are also processed in different parts of your body - so you might be following a "calories in calories out" and giving yourself non-alcoholic fatty liver disease.
3) It conflates calories, as measured via completely artificial process, with human digestion.
Calorie as a measure sets upper limit of maximum energy you can extract from a given food. If you want to gain 1lb of weight, you will need to eat at least 3500 calories. If you want lose 1lb, you have create deficits of at least 3500 cals.
Can you very easily consume more than a days worth of calories in a lot less than 6 hours eating uncooked leafy greens?
Or to make it easier how about eggs, let's say 2500 calories at ~80 calories per egg, you just need to down ~32 eggs in a few hours, maybe 10 eggs an hour?
Calling something near physically impossible "an abstraction" seems a bit oversimplified, perhaps?
> Can you very easily consume more than a days worth of calories in a lot less than 6 hours eating uncooked leafy greens?
I'm honestly not sure any human being could physically consume a days worth of calories in a whole day eating nothing but uncooked leafy greens. So the time restriction would be irrelevant to the goal wouldn't it? And that's my point, it matters more what you eat and how much of it than when you eat it. Time restriction is a poor abstraction of CICO.
I have done a TRE based diet twice, with success. The first time was Keto+OMAD, after reading Michael Mosley's Fast 800 book (which advocates a less restrictive diet but in the same vein). Result: -8 kg in 8 weeks. Also my weight was mostly stable after that, eventually trending up as my discipline waned. I have also seen up close two people suffering type 2 diabetes get it under control with the rapid weight loss afforded by this method.
Now, a year later, I am doing 8 hour eating window (not Keto) and am sticking to it for the long-term. I simply don't enjoy breakfast. Never have really. Not eating it appears to give me more stable energy and concentration for both intellectual and physical tasks, both before and after "lunch": a raw oats & berries breakfast anywhere between midday and 4 PM depending. I also run 5 km every second day, heavy weights once a week. Reuslt: -0.75 kg/week averaged over many months. Now my weight is somewhat stable at a healthy weight.
I wholly accept that this is most likely de-facto calorie restriction and not the wonders of TRE per se. Early in Fast 800 Dr Mosley addresses diet adherence and it is widely believed that this is the single biggest factor impacting diet for weight (fat) loss success.
With respect to cellular regeneration, I like the story but the only sources I've found (and they're not scientific so do your own searching) is that this process starts at about 16 hours of fasting. It really peaks around 3-4 days of fasting, which is a whole different thing. I have started doing occasional 2 day fasts and want to say it's do-able by normal people, but so far it appears TRE won't get you anything like it.
> The other factor is the supposed ‘cellular regeneration’ kinds of claims, along the lines of “well, if your cells arent metabolizing fresh food, they have time to do clean—up processes and this is good for reasons”. I would be interested to learn more along these lines, but it makes sense that this wouldn’t be directly related to weight loss as such and would instead affect other factors (longevity, gut and skin health, etc)
I have seen a lot of post from people on fasting subreddit with pictures of skin condition improving/gone after fasting.
It does make sense that our bodies take path of least resistance, and when there is no food around the cellular 'garbage' becomes something can be recycled into food.
This is somewhat of a meta-comment but why is nutrition research so challenging and contentious even in 2020?
What prevents us from developing tools, whether statistical techniques or otherwise, from settling these questions once and for all? And why do the answers need to be universal? Most papers I've read do not universalize their results, at least outwardly, but (some) popular science writers seem to do that a lot.
I can imagine, and several other comments allude to this, that individuals with different genetic makeup will experience a different set of dynamics around nutrition. I don't mean to be facetious or to suggest these aren't real challenges, I'm just curious on what the big obstacles are, in 2020.
Take for instance, a diet. It's incredibly difficult to assess compliance with a diet (especially when the diet does not call for precise to-the-gram measurement of ingredients). The best way to make this work is to feed the subjects in the lab (and pray that they don't cheat!). This is expensive, and it's difficult to recruit subject for such constrictive experimental parameters.
Also it goes without saying, but statistical tools won't save you if your data is garbage.
Add to that the fact that biology is mindbogglingly complicated. Different genetics, epigenetics, microbiome, food supplier, or other environmental factors could cause completely different effects with the same exact intervention. It's hard or impossible to isolate individual effects in such a large multivariate system with very nonlinear interactions.
>This is somewhat of a meta-comment but why is nutrition research so challenging and contentious even in 2020?
A substantial long term study, with many experimental subjects, is more costly to fund, and produces much less papers than 10 or 20 hastily done studies. The system optimizes for more papers and easier funding.
Plus, research/university ties with industry means the industry (glorified telemarketers) says jump and researchers say "how high". Bad results that promote a product/supplement/fad diet can be way more profitable than good research.
It's not complicated. People keep needing to spin something new in order to maintain ratings, clients, etc..
Meet all RDAs with just a variety of whole quality foods, 1:1:1 calcium:phosphorus:magnesium ratio, and ensure sufficient quality sleep (sustained-release melatonin after growth plates fuse).
Anything else is based on genetics, something that can be known and analyzed nowadays. For example, I learned I have issues with saturated fats. Some learn they have methylation/MTHFR mutations. Etc.
Most things done are to maintain youthfulness, looks, etc. Mostly noise, though, save the basics mentioned above.
I’m really happy to see publication of a study that did not confirm a hypothesis. I think it’s important to see things that we tried that didn’t work out, as well as seeing studies that confirm hypotheses.
I don't think this is the first research to show this. What I have seen though is that time restricted feeding (specifically where you eat in the morning, not at night), can positively impact blood glucose levels.
Burt Herring, the author of the Fast-5 diet book, contends that doing physical activity while fasting causes the body to reach into fat reserves for energy. This seems plausible to me, but IANAD.
In any event, I've been able to lose 30+ pounds over the past several months by going for regular walks and (mostly) refraining from eating anything with calories until evening. Interestingly, I also find that my food intake capacity at dinnertime seems to be less than it used to be.
Absolutely works for me. Time restriction is the only "way of eating" for me that's ever been able to maintain results for years on end without yoyo-ing.
I'm not sure why the study was designed this way, but it seems poorly thought out. 16 hours of fasting is eating dinner at 6pm and then going to brunch the next morning. They really should have done 20 or at least 18 hours. My personal feeling, is that there are a whole bunch of factors involved, and time restricted eating is one of them. I'm looking forward to the science being done on this.
Precisely. If I fast for 16 hours it does not do much. As a male in early 40s I have to hit atleast 18-20 hours of fasting to start seeing a difference. I have to restrict sugar intake also during the 4-5 hour eating window.
The theory of fasting in this situation is that once your body burns the available food-fuel, various systems are impacted. So, if that is correct, you would see a change towards the end of the fasting period. A longer period would therefore be expected to show more change.
16 hour fasting seems to be the most popular form of intermittent fasting (especially as a way to lose weight), so I think it makes sense to focus on it.
If you've ever gone down the internet rabbit hole of intermittent fasting (which I don't recommend!) you'll find that people shoot for 20/4 or at least 18/6. 16/8 is the beginner version.
I am Confused about why Conflict of interest is not being mentioned if Lead Researcher is a Clinical Consultant(https://www.linkedin.com/in/dylan-lowe-phd/) at
https://getkeyto.com
I am sure Time restricted eating would compete with Keto Diets and may have an impact on the business for such companies.
> Conclusions and Relevance Time-restricted eating, in the absence of other interventions, is not more effective in weight loss than eating throughout the day.
I have been following a 16:8 routine during lockdown and have found a modest weight loss, but there are loads of confounding factors - I find myself eating healthier, i have been running 5ish K each day etc.
That's all under the heading of "eating healthily and exercising". But looking for one specific item in a whole life change is looking at the wrong problem.
We are looking in the wrong place here - we live in an "obesogenic" world - rather than looking for a fix that helps us live with aisles in super markets stuffed with sugar and crisps, shouldn't we take those aisles away? A coffee shop does not need cakes, just good company. A fast food takeaway does not have to be fried.
It's not the fault of each of us as individuals that (so many) of us cannot resist what we are programmed to eat.
It's the fault of "us" as society - we talk about designing better cities, more walkable, more community - it one of those designs we also need is access to healthy food.
Nobel laureate Richard Thaler talks about a Libertarian Paternalism - i think we need to consider something like it.
Fell off the intermittent fasting bandwagon recently. For some reason the intermittent fasting crowd is also usually a big fan of ketosis. I have recently switched to high starch very low fat, eat whenever you want. No added oil, no animal products. Immediately lost about 10% of body weight in first 3 months. Recommend fellow recovering keto-ers please look at the starch diet advocated by John McDougall.
This is certainly not true for me. Fasting 16 hours a day has changed my life. I eat relatively healthy but been eating a lot of sugar, full pizzas etc so I doubt I’m at a calorie deficit more than once a week.
As an aside, I had cancer and worked with surgeons professionally. And I am exceptionally skeptical and disappointed in the curiosity of doctors and surgeons. Some of my doctors would repeat word for word answers. My oncologist didn’t know basic questions.
> Time-restricted eating, in the absence of other interventions, is not more effective in weight loss than eating throughout the day.
I believe this, with two additions: In my experience, time restricted eating confers weight loss via reduced calorie intake (in short, if I only eat until I’m full for a 6 hour period in a day, I simply don’t eat as much).
The other factor is the supposed ‘cellular regeneration’ kinds of claims, along the lines of “well, if your cells arent metabolizing fresh food, they have time to do clean—up processes and this is good for reasons”. I would be interested to learn more along these lines, but it makes sense that this wouldn’t be directly related to weight loss as such and would instead affect other factors (longevity, gut and skin health, etc)