8 ms·

Effects of Time-Restricted Eating on Weight Loss and Other Metabolic Parameters

59 points by voisin 6y ago

dt3ft 6y ago
Huh, wasn't expecting this: > Conclusions and Relevance Time-restricted eating, in the absence of other interventions, is not more effective in weight loss than eating throughout the day.
- mahalol 6y ago
  From my experience, I simply end up eating more after breaking the fast, so overall the same amount of calories a day (if not more).
seebetter 6y ago
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.
- technoplato 6y ago
  When you cite your skepticism, are you saying those doctors aren’t exploratory in their opinions of diet? How did you work with these doctors in a way that’s relevant to the topic? Apologies for my ignorance and assumptions but wouldn’t you need to gain weight after surgeries for cancer?
c54 6y ago
They conclude the following: > 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)
- AnIdiotOnTheNet 6y ago
  > (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.
  - andrei_says_ 6y ago
    What is CICO? Do you mean something like calories in calories out? And doesn’t that disregard the fact that sugar calories are very different from non sugar ones in terms of metabolism?
    - amelius 6y ago
      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.
      - matz1 6y ago
        How is it disrespectful?
        deleted 6y ago
        [deleted]
        johnkpaul 6y ago
        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!”
lifeisstillgood 6y ago
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.
- deleted 6y ago
  [deleted]
issa 6y ago
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.
- shekharshan 6y ago
  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.
- ImprobableTruth 6y ago
  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.
  - issa 6y ago
    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.
- fredophile 6y ago
  Why would 18 or 20 hours be better than 16? What would happen physiologically in the extra 2-4 hours of fasting that didn't happen in the first 16?
  - issa 6y ago
    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.
newobj 6y ago
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.
joshgel 6y ago
Previous discussion here: https://news.ycombinator.com/item?id=24622280 https://news.ycombinator.com/item?id=24622280
Rich_Morin 6y ago
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.
staticassertion 6y ago
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. https://pubmed.ncbi.nlm.nih.gov/31151228/ https://pubmed.ncbi.nlm.nih.gov/31151228/ (First I found via search, not sure if it's the initial one I'd heard of) That may not necessarily impact weight loss/ gain directly, but it's certainly critical for health.
efitz 6y ago
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.
sharker8 6y ago
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.
deleted 6y ago
[deleted]
andrewjl 6y ago
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.
- norswap 6y ago
  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.
  - ehsanu1 6y ago
    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.
- baccheion 6y ago
  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.
irfn 6y ago
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/ https://www.linkedin.com/in/dylan-lowe-phd/) at https://getkeyto.com 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.

59 points by voisin 6y ago

Huh, wasn't expecting this: > Conclusions and Relevance Time-restricted eating, in the absence of other interventions, is not more effective in weight loss than eating throughout the day.

mahalol 6y ago
From my experience, I simply end up eating more after breaking the fast, so overall the same amount of calories a day (if not more).

seebetter 6y ago

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.

technoplato 6y ago
When you cite your skepticism, are you saying those doctors aren’t exploratory in their opinions of diet? How did you work with these doctors in a way that’s relevant to the topic? Apologies for my ignorance and assumptions but wouldn’t you need to gain weight after surgeries for cancer?

c54 6y ago

They conclude the following: > 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)

AnIdiotOnTheNet 6y ago
> (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.
- andrei_says_ 6y ago
  What is CICO? Do you mean something like calories in calories out? And doesn’t that disregard the fact that sugar calories are very different from non sugar ones in terms of metabolism?
  - amelius 6y ago
    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.
    - matz1 6y ago
      How is it disrespectful?
      - deleted 6y ago
        [deleted]
      - johnkpaul 6y ago
        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!”

lifeisstillgood 6y ago

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.

deleted 6y ago
[deleted]

issa 6y ago

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.

shekharshan 6y ago
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.
ImprobableTruth 6y ago
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.
- issa 6y ago
  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.
fredophile 6y ago
Why would 18 or 20 hours be better than 16? What would happen physiologically in the extra 2-4 hours of fasting that didn't happen in the first 16?
- issa 6y ago
  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.

newobj 6y ago

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.

joshgel 6y ago

Previous discussion here: https://news.ycombinator.com/item?id=24622280 https://news.ycombinator.com/item?id=24622280

Rich_Morin 6y ago

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.

staticassertion 6y ago

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. https://pubmed.ncbi.nlm.nih.gov/31151228/ https://pubmed.ncbi.nlm.nih.gov/31151228/ (First I found via search, not sure if it's the initial one I'd heard of) That may not necessarily impact weight loss/ gain directly, but it's certainly critical for health.

efitz 6y ago

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.

sharker8 6y ago

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.

deleted 6y ago

[deleted]

andrewjl 6y ago

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.

norswap 6y ago
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.
- ehsanu1 6y ago
  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.
baccheion 6y ago
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.

irfn 6y ago

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/ https://www.linkedin.com/in/dylan-lowe-phd/) at https://getkeyto.com 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.