review of Time Restricted Eating studies

[Bongleur]

Looks like no studies on healthy people wrt optimizing fitness.

https://www.medscape.com/viewarticle/953817
News > Medscape Medical News > Conference News > ADA 2021
Time-Restricted Eating Is 'Promising, But More Data Are Needed'

Marlene Busko
June 26, 2021

Time-restricted eating — that is, reducing the number of hours a person is allowed to eat during the day — may produce a modest 1% to 4% weight loss, even without cutting calories, early studies in humans suggest. But more research is needed to provide definitive evidence.

This type of intermittent fasting also appears to improve blood glucose, blood pressure, and oxidative stress, said Courtney M. Peterson, PhD, a researcher at the University of Alabama at Birmingham, summarizing what is known about the potential weight-loss strategy at the virtual American Diabetes Association (ADA) 81st Scientific Sessions.

The best results were seen with early time-restricted eating (that is, ending the nighttime fasting early in the day) and allowing a person to eat 8 to 10 hours each day (eg, 8 AM to 4 PM or 8 AM to 6 PM), with fasting and only water allowed the remaining hours, she reported.

However, the three dozen or so studies in humans to date are mainly small, pilot, or single-arm studies lasting up to 3 months, and there are only three main randomized controlled trials with 25 or more participants in each group.

Large trials with around 260 participants are needed,
SNIP

 

[audreyh1]

Time restricted eating is an easy way to drop insulin levels in people who have excess insulin due to metabolic problems including type 2 diabetes. So it’s not surprising that the focus would be on folks with metabolic disease. I have never heard of it as a way to optimize fitness in healthy people.

I have heard of very low carb used by elite endurance athletes to improve their performance. That’s a very different approach. It results results in low insulin levels all the time making it easy for the body, once adapted, to readily burn its own stored body fat as needed for fuel all the time.

Time restricted eating helps with type 2 diabetes/insulin resistance and weight loss because having a long enough period for blood insulin levels to drop allows the body to burn some of it's own fat. Insulin acts as a switch: if it's high, the body cannot burn its stored fat and also will also store any food not immediately burned as fuel as fat for later use; when it's low, the body can readily draw on it's fat reserves. So chronically high insulin acts as a trap where the body readily stores fat yet cannot burn it. Hyperinsulinemia is understood to be the root cause of metabolic disease. https://pubmed.ncbi.nlm.nih.gov/14527633/

Time restricted eating also has the elusive yet powerful benefit of autophagy. Autophagy recycles old damaged cells and proteins creating new healthy ones, but it doesn't start happening until a (water only) fasting period of at least 12 hours.

 

[Aerides]

I can't find the article right now and will post if I do, but there was a study done in the past couple of years which showed that while IF did mean more weight loss, the proportion of lean muscle mass lost was higher than traditional diets.

IOW - the IF folks might lose 7 lbs vs. 5lbs, but their 7 was closer to 60/70% losing the good stuff. Regular diets it's more the reverse where fat is more than 50% of the weight loss.

After I read that, I started having a protein shake for breakfast. It's hard, I did IF for years and it became my lifestyle, but I work very hard for every little muscle and want to keep those over any other goal.

 

[karen1972]

I joined an IF reddit group, there are 1000s of people on there losing like half their body weight, so not sure it would be hard to find people to study. We did a month of IF, doing the 5:2 and both of us not only noticed weight loss but noticed on non-fasting days we were fuller faster and ate smaller portions.

 

[Amethyst]

This doesn't sound very restricted to me. It sounds like how we typically eat. Hmm never realized we were "fasting." Just not eating when we are not hungry.

https://www.medscape.com/viewarticle/953817
News > Medscape Medical News > Conference News > ADA 2021
Time-Restricted Eating Is 'Promising, But More Data Are Needed'

Marlene Busko
June 26, 2021

The best results were seen with early time-restricted eating (that is, ending the nighttime fasting early in the day) and allowing a person to eat 8 to 10 hours each day (eg, 8 AM to 4 PM or 8 AM to 6 PM)


SNIP[/QUOTE]

 

[audreyh1]

This doesn't sound very restricted to me. It sounds like how we typically eat. Hmm never realized we were "fasting." Just not eating when we are not hungry.

https://www.medscape.com/viewarticle/953817
News > Medscape Medical News > Conference News > ADA 2021
Time-Restricted Eating Is 'Promising, But More Data Are Needed'

Marlene Busko
June 26, 2021

The best results were seen with early time-restricted eating (that is, ending the nighttime fasting early in the day) and allowing a person to eat 8 to 10 hours each day (eg, 8 AM to 4 PM or 8 AM to 6 PM)


SNIP

It is definitely more restricted. Typical eating is more like maybe 8AM to 7PM, or 7AM to 7PM. People may start dinner at 6PM, but they are eating past that time. And many end their meals quite a bit later, yet have breakfast first thing in the morning. Not to mention after dinner snacking and drinking sodas or other non-water/black coffee beverages that many indulge in later.

8AM to 4PM is quite a bit different. You have to completely finish eating by 4PM. And no drinks afterwards either other than water or unsweetened coffee/tea with minimal cream.

I think what it shows instead is that seemingly minor adjustments make a big difference. In particular finishing meals by a certain time. Yes, even just a few hours. And there is more going on, because it also completely cuts out after dinner snacking, later desserts, and drinking of all but a few limited beverages that don't break a fast.

 

[Amethyst]

It sounds a lot like Mom's advice: "Don't snack between meals." Being very short, she kept her weight below 105 pounds all her life, so knew something about it.

it also completely cuts out after dinner snacking, later desserts, and drinking of all but a few limited beverages that don't break a fast.

 

[karen1972]

8AM to 4PM is quite a bit different. You have to completely finish eating by 4PM. And no drinks afterwards either other than water or unsweetened coffee/tea with minimal cream.

I think what it shows instead is that seemingly minor adjustments make a big difference.

Agreed, its really those 2-4 extra hours of being in the fat burning zone that seems to make the difference as most people I know even if they don't snack have only 12 hrs inbetween meals, not 14-16 hrs.

Even as a kid, breakfast was at 7AM in order to make the bus, supper was 6:30 PM when dad got home from work, so by the time done eating 7.

The people I saw that were really losing a ton of weight I'm sure are saving a ton of calories cutting out the late night snacking, I was always told, no food after 7, but these studies are showing even that is too late.

 

[audreyh1]

It sounds a lot like Mom's advice: "Don't snack between meals." Being very short, she kept her weight below 105 pounds all her life, so knew something about it.

Absolutely. Snacking and continuous grazing is a big problem in the US.

But what you drink after dinner and before breakfast matters too.

 

[chassis]

Looks like no studies on healthy people wrt optimizing fitness.

https://www.medscape.com/viewarticle/953817
News > Medscape Medical News > Conference News > ADA 2021
Time-Restricted Eating Is 'Promising, But More Data Are Needed'

Marlene Busko
June 26, 2021

Time-restricted eating — that is, reducing the number of hours a person is allowed to eat during the day — may produce a modest 1% to 4% weight loss, even without cutting calories, early studies in humans suggest. But more research is needed to provide definitive evidence.

This type of intermittent fasting also appears to improve blood glucose, blood pressure, and oxidative stress, said Courtney M. Peterson, PhD, a researcher at the University of Alabama at Birmingham, summarizing what is known about the potential weight-loss strategy at the virtual American Diabetes Association (ADA) 81st Scientific Sessions.

The best results were seen with early time-restricted eating (that is, ending the nighttime fasting early in the day) and allowing a person to eat 8 to 10 hours each day (eg, 8 AM to 4 PM or 8 AM to 6 PM), with fasting and only water allowed the remaining hours, she reported.

However, the three dozen or so studies in humans to date are mainly small, pilot, or single-arm studies lasting up to 3 months, and there are only three main randomized controlled trials with 25 or more participants in each group.

Large trials with around 260 participants are needed,
SNIP

Thanks. The article is behind a "free subscription" wall that I declined to jump over.

The need to lose half of one's body weight is a medical emergency, and I hope this doesn't apply to many people.

So if as Bongleur says, there are no studies on healthy people wrt to optimizing fitness and intermittent fasting, what are people to do, who do not need to lose half of their body weight?

For people with stable, healthy weight, what does a .gov- or .edu- reviewed study say about intermittent fasting? Are there any such studies, or is that what Bongleur means when making the statement "no studies on healthy people"?

 

[audreyh1]

I’m a few days in on an interesting 14:10 experiment now. Mainly trying to work out my daily schedule and see how it goes for two weeks.

I had trouble in the past with early evening/afternoon meals interfering with my sleep schedule as well as challenging with my usually afternoon workout schedule. This time I’m trying later breakfasts instead. It’s quite different because I find myself looking for things to do first thing in the morning, and I’m getting a lot of extra chores and projects done before breakfast.

I’m doing water only during the fast. That’s part of it. No relaxing with a hot cup of coffee before breakfast.

 

[Scuba]

I just started IF because my weight loss was going too slowly and I wanted a method that could accelerate it to a more reasonable pace (2 lbs a week instead of 0.3j. It’s only been a few days, nut I like it so far! I think it is a lifestyle I can continue.

I chose to try a 16:8 schedule. I had to get over the mental block I had that “breakfast is the most important meal of the day” and the belief that I couldn’t exercise on an empty stomach. So far it is really working for me to skip breakfast, eat a late lunch, and have a later dinner. I’ve never been a big snacked after dinner but this certainly eliminates that as an option.

 

[RAE]

I can't find the article right now and will post if I do, but there was a study done in the past couple of years which showed that while IF did mean more weight loss, the proportion of lean muscle mass lost was higher than traditional diets.

IOW - the IF folks might lose 7 lbs vs. 5lbs, but their 7 was closer to 60/70% losing the good stuff. Regular diets it's more the reverse where fat is more than 50% of the weight loss.

After I read that, I started having a protein shake for breakfast. It's hard, I did IF for years and it became my lifestyle, but I work very hard for every little muscle and want to keep those over any other goal.

Based on what I have read, you should be able to avoid muscle loss during IF if you make sure your protein intake is adequate, and you do some daily resistance exercises (lifting weights or bodyweight exercises) to help maintain muscle. A lot of older adults do not get adequate protein, and a lot do no resistance training as well, so under those conditions, it is certainly possible to lose muscle mass. I also have to work hard at maintaining muscle mass at my (advanced) age, so I make sure I do my daily bodyweight exercises and also eat plenty of protein with most meals.

 

[Aerides]

Based on what I have read, you should be able to avoid muscle loss during IF if you make sure your protein intake is adequate, and you do some daily resistance exercises (lifting weights or bodyweight exercises) to help maintain muscle. A lot of older adults do not get adequate protein, and a lot do no resistance training as well, so under those conditions, it is certainly possible to lose muscle mass. I also have to work hard at maintaining muscle mass at my (advanced) age, so I make sure I do my daily bodyweight exercises and also eat plenty of protein with most meals.

Yes, the studies showing lean mass loss didn't mention the specific diet content, other than IF, so that's certainly a consideration to combat losing the good stuff.

Still, for me I'm actively trying to gain a little muscle and strength, not just mitigate their loss. I did the skip-breakfast IF 12/8 for a few years, and it just became normal to eat that way. All I've really changed since dropping it is having a breakfast of a protein shake around 10am instead of waiting till lunch for anything. I still don't have a normal breakfast appetite most days.

 

[audreyh1]

I’ve never seen an article saying that time restricted eating causes muscle or lean body mass loss. Certainly Dr. Jason Fung doesn’t think so.

But if someone doesn’t have adequate fat stores and us already lean I could see how there might be issues without adequate intake.

I also notice that although Dr. Fung focuses on time restricted eating in his talks, he also counsels his patients to lower carbs and just eat real food - not highly processed food is or junk.

 

[RAE]

This may be the study that Aerides is referring to:



https://www.phillyvoice.com/intermittent-fasting-diet-weight-loss-method-muscle-loss-research/


This study, however, has been criticized by some (for various reasons), so I wouldn't necessarily put too much stock in it. I do think, though, that you need to make sure you are getting adequate daily protein (to help maintain muscle mass), and do at least some resistance training, whether you are practicing IF or not.

 

[googily]

I have been doing time-restricted eating for years without really realizing it, once I stopped forcing myself to have breakfast (in my intuitive eating days). 16/8 is pretty much my standard. I can sometimes do 18/6 or 20/4 or even 23/1, but anything beyond that seems ultimately counterproductive.

I found myself whining a few months ago about how 16/8 really does nothing for me anymore--until I thought about how I weigh so much less than I did a decade ago. I think 16/8 is just weight maintenance for me now.

 

[audreyh1]

Fascinating podcast interview by Brett Scher regarding Time-restricted Feeding research.

During the interview the researcher mentioned that many subjects had previously been eating 15+ hours per day!
https://dietdoctorpodcast.podbean.com/e/80-time-restricted-eating/

 

[chassis]

Are time restricted eating, keto and intermittent fasting treatments for a problem? ie insulin or glucose control, diabetic control, thyroid management, or something else?

Are time restricted eating, keto and intermittent fasting recommended for all people?

 

[sengsational]

The theory is that minimizing the amount of time with elevated blood sugar is going to prevent disease. The ability of humans to eat foods that significantly increase blood sugar on a regular basis happened after agriculture. The body knows what to do when the human finds a tree with ripe fruit, but that week passes, and it's back to working calories out of less caloric foods. So the body is not adapted to constant elevated blood sugar, and that, the theory goes, is the cause of many disease processes.

 

[ElizabethT]

Purely anecdotal, but as someone who is hypoglycemic sensitive, I've been pleasantly surprised by how IF works for me on two fronts. One is I no longer get the shakes mid-workout, which I used to get after ingesting my 'usual' workout breakfast of a banana and energy bar, not realizing how badly my system processes even more complex carbs (I already knew it didn't appreciate refined sugar). I can do hikes up to 10 miles distance on an empty stomach and not get the shakes. In the event I bump into issues with plunging electrolytes, I do make it a habit carry tablets and almonds, but to date have not needed to use them.

On the second front, IF has been the best method I've come across to date to reduce my calories in order to lose weight. My system finds it easier to go long periods without eating, and then eat well when I do eventually, rather than to continually be ingesting small meals, which are harder for me to put the brakes on, calorically speaking. To date I've lost 15 pounds, but more imporatantly to me, it feels like a lifestyle I can keep up forever. One larger meal a day, often times enjoyed socially, then a small second meal, and that's about it.

So, while no doctor by any means, my body appears to be communicating that it really likes my IF efforts, and so I have no plans to change anything. IF is also allowing me to avoid constantly rising and plunging blood sugar levels, which often leads to the shakes and fatigue in my case, and I am feeling better than I have in years.

 

[audreyh1]

Purely anecdotal, but as someone who is hypoglycemic sensitive, I've been pleasantly surprised by how IF works for me on two fronts. One is I no longer get the shakes mid-workout, which I used to get after ingesting my 'usual' workout breakfast of a banana and energy bar, not realizing how badly my system processes even more complex carbs (I already knew it didn't appreciate refined sugar). I can do hikes up to 10 miles distance on an empty stomach and not get the shakes. In the event I bump into issues with plunging electrolytes, I do make it a habit carry tablets and almonds, but to date have not needed to use them.

On the second front, IF has been the best method I've come across to date to reduce my calories in order to lose weight. My system finds it easier to go long periods without eating, and then eat well when I do eventually, rather than to continually be ingesting small meals, which are harder for me to put the brakes on, calorically speaking. To date I've lost 15 pounds, but more imporatantly to me, it feels like a lifestyle I can keep up forever. One larger meal a day, often times enjoyed socially, then a small second meal, and that's about it.

So, while no doctor by any means, my body appears to be communicating that it really likes my IF efforts, and so I have no plans to change anything. IF is also allowing me to avoid constantly rising and plunging blood sugar levels, which often leads to the shakes and fatigue in my case, and I am feeling better than I have in years.

That’s great!

I remember a guide on a trip saying she had to eat often due to hypoglycemia and I always wondered if she could curb her insulin spikes it would go away. Eating high carbs frequently would just exacerbate the problem from what I can tell.

 

[chassis]

The theory is that minimizing the amount of time with elevated blood sugar is going to prevent disease. The ability of humans to eat foods that significantly increase blood sugar on a regular basis happened after agriculture. The body knows what to do when the human finds a tree with ripe fruit, but that week passes, and it's back to working calories out of less caloric foods. So the body is not adapted to constant elevated blood sugar, and that, the theory goes, is the cause of many disease processes.

Interesting, thanks.

Domestication of wild grains started 105,000 years ago if Wikipedia is to be believed. I believe it.

Honey was consumed by humans approx 8,000 years ago.

So for the past 8,000 years (agriculture + honey), humans have been eating in way the human body is not adapted for? Serious question.

Are most keto/time restricted/intermittent fasting practitioners generally suffering from a disorder of one kind or another? Serious question.

 

[qwerty3656]

Interesting, thanks.

Domestication of wild grains started 105,000 years ago if Wikipedia is to be believed. I believe it.

Honey was consumed by humans approx 8,000 years ago.

So for the past 8,000 years (agriculture + honey), humans have been eating in way the human body is not adapted for? Serious question.

Are most keto/time restricted/intermittent fasting practitioners generally suffering from a disorder of one kind or another? Serious question.

Until the 1970s low fat diet push, it was common knowledge that sugar and starchy carbs caused weight gain

https://youtu.be/q8BGYhreaco

 

[Sanstar]

Well, my personal experience with time restricted eating since Sept, 2020 is all positive. Mostly one meal a day which takes about an hour, sometimes both a meal and snack over 4 hours. All around mid-day. Only plants, so definitely not low carb.

Feel great, down 3 pant sizes and 40#. Labs continue to improve, blood pressure and thyroid meds cut back. Love cleaning the kitchen by 2PM and done for the day! Studies are interesting to me and I do try to keep up. I know scientists are trying to understand and fix populations. I just need to fix me.

I grew up before the obesity epidemic and as others reported, we ate most of our food from the garden and what was locally sourced. I was 12 before I had my first soda. Three squares a day and kitchen was closed after supper. No eating out and fast food hadn’t yet been invented.

Today, I see first hand the unremitting reliance on door dash, drive throughs and take out by close family members….and dialysis units in every neighborhood.