Having gone back and forth on this (a 16-hour fast for a several week period more than one time), and having read a bunch on the topic, I've concluded thus far that, fundamentally, there's no one-size-fits-all for human bodies. In other words, human bodies are so complex that results for almost any food program vary a lot.
Aside from the individual factors, which include your gender and age and whatever uniqueness about your body that we don't know yet (like effects of gut flora on metabolism), there's the type of exercise you do.
If you do long distance running or cycling, at one extreme, it's obviously a no-go. If you do a short conditioning workout or strength workout right before breaking your fast (if you're lucky enough to have a schedule that allows that), that sounds okay.
There's some speculation that fasting 'resets' the gut flora, or that there's a benefit to 'giving the digestive system a rest', then there's some science around the impact on fasting on circadian rhythm reset benefits, some other science around fasting to 'reset the immune system.'
My personal experience was that I didn't get much benefit in terms of body fat cutting, I didn't notice a performance increase or decrease in the gym (where I do strength training and calisthenics primarily with a bit of cardio). I DID notice I was obsessing over food in the mornings and when 2pm came around, there was a feeling of accomplishment.
I'm not sure it was worth it for me. As for everyone else, the jury's still out. It's just that I'm not convinced it'll be back within my lifetime in this complex area of study.
>If you do long distance running or cycling, at one extreme, it's obviously a no-go.
This isn't obvious to me. I don't run seriously, but I don't find that fasting has any adverse effect on my performance. If you are talking about running a marathon or something like that, then sure, but hardly anyone is doing exercise that intense multiple times a week, so you could still have fast days.
16 hours really isn't a very long time to go without food. Your body can cope with it fine, even if you're doing quite intense exercise.
>If you do long distance running or cycling, at one extreme, it's obviously a no-go.
I always do my runs in the morning, right out of bed, fasted. Your body is very good at storing energy and using it later, I've had no issues (if anything, trying to eat before a run just causes problems for me).
So Jason Fung is actually misreading this study. The main issue around all of this is: If someone eats the exact same amount of calories but spreads it out throughout the day does this have any effect on metabolism or weight? So far IF proponents have had a really hard time showing isocaloric diets have any different outcomes regardless of meal timing. This study attempts to address this issue by serving the same amount of food, but it does not ensure that the same amount of food is consumed, and so we are right back to where we are with all IF studies that show results like this: IF contributed to the participants abilities to eat the right amount of food, but there is still not a single study showing isocaloric intake and any different outcomes.
Besides that the standard: this is done on 8 people over a very small period of time, so it's at best a pilot study anyway.
IF may be a great way for some people to comply to their dietary goals better, but there is still not a single study that shows it actually does anything besides that.
> I've concluded thus far that, fundamentally, there's no one-size-fits-all for human bodies
Exactly. I've had pretty bad experiences with a no-breakfast IF. After two or three weeks on the diet, I get insomnia, and I definitely feel more stress. On the latter, I've read that IF raises cortisol levels, so that might be it. That's actually pretty good when you're at low baseline stress levels (it puts you in a state of "positive anxiety"), but when you're stressed from work it can take you over the limit.
Ultimately I stopped it because I'm already at around ~12% BF - I couldn't even say why I was doing it anymore. Three healthy meals a day and regular exercise does it for me.
If this works for people without negative consequences, then all the more power to them. I really like how it goes against the "shove things into your mouth at every waking hour" philosophy, which has become a ridiculous dogma in modern society.
What about water fasting for longer periods? Have you gone 24/48/72 hours without any food? I find that longer fasts tend to work better for me, since I end up eating more calories in the 8 hours window in a 16/8 IF regime. But if don't eat for close to 36 hours, even with the increased food intake, I would still come out ahead.
If you fast long enough, say 48 hours I think, your body enters a mode of "autophagy", which is highly beneficial. So there's that.
> If you do long distance running or cycling, at one extreme, it's obviously a no-go
I did a one week Buchinger fasting and did several long distance runs (as I always do) after 2 days fasting. (after switching to cetogen burning)
I noticed a small decrease in power, but in no way this was a no go. It was actually fun.
As you point out there are cycles that will influence the experience of a fast - not limited to physical energy available at any time, possible discomfort due to coping mechanisms food/eating may part of, and so on. I am still managing significant chronic pain, and although sugar is bad for inflammation - which has its own problems - it is "comforting" and numbs the pain to some degree as well. I generally go through cycles of pure water fasting for 3 days to break the sugar cravings and to bring back mental clarity, at the cost of the remaining pain localizing and becoming sharper. Still waiting for refuge from pain, potentially some more healing next week, and then have to wait another ~3 months for another stem cell treatment.
To all those who replied saying they fast and do long distance running, I guess I stand corrected. But I'd be concerned about muscle catabolism, as if the body is asked to retrieve energy due to demands placed on it, surely after a prolonged fast the muscle tissue is a strong candidate.
Did you continue to eat high-carb meals after your fasting? I recently had to give up eating keto for a few weeks and then I noticed I got very hungry in the mornings. On keto I would normally eat around noon without much effort. If your body gets used to high insulin it will naturally make you crave food more often.
My experience with time-restricted eating has been that, regardless of the benefits of the fasting itself (which FWIW I do believe in), it has brought one significant change into my life: caring much more about the nutrition of each meal I eat.
Before I began fasting, I found myself saying things like, "Well, this isn't great for me, but it'll be filling for a few hours and then I'll eat something else." With IF that is not an option, and it forced me to more carefully consider whether I was providing my body with the proper fuel for the next X hours.
Similarly, coming out of the fast, I was much more likely to eat nutritionally-valuable foods because I knew that whatever I put in my body it would immediately consume for fuel and I wanted to give it something valuable.
That in itself has led me to rave about IF to anyone who is interested enough to listen. I recommend at least an experiment with it to experience that consideration of nutrition, because I think that will stay with you whether you stick with IF or not.
I'm 485. I had gastric sleeve surgery in 2012 at 650 (after losing 40 through liquid diet).
5 weeks ago I was 515. I started a fitness challenge at a CrossFit gym, I workout 4 days a week, I eat Keto, and I (sometimes) eat just one meal a day. I find it really hard, like extremely hard when doing IF to get all my protein in for the day.
I kid you not, because of my stomach size, the keto effects (lower hunger), and only having an hour or two window for food when I stick to IF completely I can't get more than 50 protein, and 600 calories.
This week, I've modified it to fit my body, I've added body fortress protein which 1 scoop in almond milk = 8 carbs, and 60 protein (my daily minimum). I eat this around 11 or noon. Then I try to have my 1 meal at 5pm. Is it IF? Not completely, but I feel for me it works a lot better.
I can probably still get only 600-800 calories a day; example: 2 burgers + 1/4th cup cheese and a dab of mayo and I'm stuffed to capacity, it takes an entire hour to finish this much food, but at my weight that's no biggie, the biggest thing is getting protein so my weight lifting at CrossFit has good results.
I'm no expert on physiology, so if anyone has tips to maximize my progress (I'm about losing more (fat) and gaining more(muscle) as fast as humanly possible).
Physically I feel like a million dollars, depression is mostly gone and anxiety as well. I'm a little obsessed on my diet/exercise regime, not sure that's bad. I started taking Vyvanse for ADHD so that also curbs appetite/hunger and has helped me focus more on my code/work. Last year I had major depression with dark thoughts, this year I feel like a different person, I'm also seeing a therapist for that stuff as of a few months ago.
Because you've had that surgery and your stomach size maybe intermediate fasting isn't the best way for you in the end?
Instead a high fat low carb diet where you really minimize carb intake (and obviously avoid all things sugary). You can get the same keto effects if you follow this approach.
This way you can easily eat several times a day and get all protein and calories you need.
Of course you can mix and match IF with this as well.
> I'm a little obsessed on my diet/exercise regime, not sure that's bad.
Be mindful. Obsessions always lie at the edge of turning bad.
Also if you've only done this 5 weeks it's easy to do too much too soon and if a time comes when you can't hold the same extreme tempo you risk a crash. This has happened to me many times. For example I've started a new training form and I train it a lot. But then I don't have the same drive like last week and a miss a single training. Then another one and suddenly I haven't trained for a month.
I am not an expert on psychology, but your goal "losing more (fat) and gaining more(muscle) as fast as humanly possible", might be detrimental to your success.
It probably took decades to get to your current body weight. Should it not then take at least 5 years to get back to your target weight ? True the caloric math shows you could probably get to 250lbs in a year with a 600-800 a day diet. But can any human actually stick with that diet for more than a month ? If not, you would be better eating 1600-1800 a day if you could stick with it for a year.
As an aside, at times I wonder if our obesity epidemic is in part related to an ever increasing target/acceptable weight. When I was a kid, if you could pinch an inch, you were overweight (I stop drinking calories if I pass the threshold). Even my childhood bathroom scale maxed out at 250 which implied that 250 must be extreme morbid obesity.
I know this is personal, but when you were young did you ever have such thresholds (weight, mobility, etc.) in mind ? Or did it just sneak up on you and by then you were in gaining weight at a surprising rate beyond your control ? No worries if you are too busy to respond. I wish you the best!
There is some good evidence (both studies and anecdotal) that there is some muscle memory in the sense that it's easier to regain muscle that was lost than to build it in the first place. So even if you lose some muscle during this whole thing, you should be fine. You want your body to be in as much in ketosis as possible; it has a huge reserve after all.
I'm sure you've seen or heard of this case study of the Scottish man who fasted 382 days [pdf]! Of course, he did it under medical supervision. But I think it's an important case of what CAN be accomplished.
I have no advice, but applause and encouragement. Keep going and congrats on your progress so far. Don't stop or get complacent - you can be a motivator for other people and your progress can be a positive force for more people than just yourself
Congrats! For the long run you might consider throwing in a day with multiple meals and significantly higher calories every now and then, sticking to whole foods for the most part. This might be good for your micronutrient intake (which I'm pretty sure does not cover the RDAs on 600-800kcals) and your metabolism, which might get wrecked in the long run otherwise.
I can recommend cronometer.com for tracking food, this might be a pain in the beginning, but gives you good insight on what your nutrient intake is. Helped me to create a diet with roughly balanced meals.
I'm not a nutritionist or broscientist, but of what I do know, what you are doing now is correct, and probably qualifies as a muscle-sparing fast.
You can eat more protein--likely in drinkable form due to your sleeve--to try to gain more muscle, or you could stay the course to lose the fat first. Since lean muscle mass increases your base metabolism, which increases your fat-burning rate, that's a complex equation that may require calculus to optimize, and your body can always just arbitrarily veto the mathematical results.
I suspect there's no objective way to discuss a topic while it's in the hype cycle. Mindnfulness meditation seems to have dubious benefits, the uberman sleep cycle has all but disappeared, but during their hype cycles there was no way to sit down and discuss whether they actually do anything. There were too many people singing praises and making tons of claims, and there's really no way to dispute them. The science seems to never happen on these types of things as well, so just waiting doesn't seem to be the answer either.
For all we've done in science, it seems like we still have a huge correlation != causation issue.
I just had someone tell me that the amount of auto accidents increase between 2 and 4pm in the US. This somehow showed that people make poor decisions during that time because of our sleep cycles? I was met with much resistance when I pointed out that there are fundamentally different people driving during 2 and 4pm than 8am or 5-6pm. The numbers don't lie, right? Just how you read them...
Anyway, I'd love to see the science that mindfulness and meditation have dubious benefits. I am such a believer in those practices, I have a hard time understanding the argument that they are not beneficial.
Intermittent fasting seems like it'd wreck your body if you do moderate to intense exercise. So I just fasted, and now I want to do intense cardio.... but I might run out of glycogen or blood sugar. Or I may do a set of weight lifting, but not if I can't eat protein after. So if I do intermittent fasting, I have to come up with a complex schedule to follow in order to get any performance gains.
The whole point of a diet is to be healthy. You don't need intermittent fasting to be healthy. It seems to just introduce complication for a menial improvement in a few measures of health. I'm sure they work, if you can actually stick to them, but there's a lot simpler diets that will also work.
Exercise three times a week. Eat lots of plants. Keep your fat, protein, and simple carb levels within reasonable limits for your age, height and sex. That's not super complicated to follow, and it can fit into basically any schedule.
As always for this kind of article, some of the comments have turned to more general discussion of human diet and metabolism. There was an very interesting article relevant to that in Vox.com a little over a month ago [1]:
"What I learned about weight loss from spending a day inside a metabolic chamber"
I dislike articles like this as they continue to perpetuate the belief that there are secrets to weight loss. There are no secrets to weight loss. Eat fewer calories than you burn. It doesn't matter if that involves keto, or vegan, or one meal a day. Thyroid problems also don't change physics.
The problem is made worse because overweight people typically greatly underestimate how much they eat, while underweight people (me most of my life) typically greatly overestimate how much we eat. It's nearly impossible to accurately gauge calorie intake without strict calorie counting.
When talking nutrition with people, I'll often bring up the examine.com piece on "does metabolism vary between two people?"(1) And I am always amazed to find at least one person in any conversation that will flat out deny the information presented there. they are positive that if they ate one single slice of pizza a day and nothing else, they would still be fat.
Given that poor sleep quality exacerbates insulin resistance, it is possible that by not eating late into the day, the research subjects in the article's fasting study may have also lost weight because their sleep improved.[1]
Personally if I eat dinner after 5PM, I have trouble sleeping.
My question in this article is: What were the properties of the participants in this study?
According to the paper these "eight overweight men
with prediabetes [...] had a mean BMI of 32.2 ± 4.4 kg/m2" (page 3).
The metabolism of these people is quite different compared to a healthy human. These were sick people. And they received a strictly controlled and monitored diet according to the paper.
I have been experimenting with weight loss for the past year. My goal it total weight "control" _not_ loss. Anyone can lose weight, I want to never ever worry or think about it again.
Today I am at a low of 181.2lbs. I haven't been this weight for probably over 12 years.
Last summer I did a month of running 6 days a week (increased distance as I went) + 1 meal a day (strict). And lost .5-.6lbs a day in 30 days. I went from 202 to 187. I gained some of it back by December. I was fluxuating between 192-195.
Then I changed my tactic, did strength exercising for one month, got up to 198, didn't lose weight at all.
Current experiment: I changed two things -
1. I said "it's ok/fine/good to be hungry". I now naturally eat one meal a day, I eat when I want, but I don't fool myself. Sometime I eat only a couple bites of something to ease my stomach.
2. No exercise during this time at all. No running, lifting, pushups, nothing.
I have gone from 198 to 181 from last January to Oct, 2018. (17lbs) Not eating is what makes you lose weight. Being hungry is your body telling you it's eating fat. I even went to a wedding, gained 3 lbs in 3 days, and shed them again 3 days later. (obviously not all of it stuck on me in the first place)
After awhile you get used to being hungry, your diet matches your need and intake. Be hungry, control your weight, it's liberating. I never have to worry again the rest of my life how to manage my weight.
TL;DR: there's no need to feel hungry, you can graze on plain intact vegetables all day long. Use calisthenic exercise to keep you honest through feedback.
My experience going from 225lbs to 165lbs and keeping it there for over a decade now +-5lbs suggests there's no need to feel hungry at all, as long as I'm eating the right foods.
I didn't use any exercise, just removed sugars and most refined carbohydrates and processed foods in general. Most the food I eat by volume is raw organic produce. I can eat plain heads of lettuce all day long and I will not gain weight. I eat canned wild sardines, salmon, and sometimes tuna for protein and omega-3s, with the occasional (~weekly) meat binge.
Once my weight stabilized at 165, physical activity became a lot more appealing so I started hiking, running, doing hand stands, pushups, generally being more active and this has given me a more masculine physique but doesn't seem to play much part in maintaining my weight.
Sometimes I experiment by ceasing most physical activity for a week or two, and mostly what happens is I become less sexy looking, the weight is more or less the same with the uniform mostly-produce diet. My mood does deteriorate though.
When I deviate from the diet, usually for social reasons, eating meat more often or letting more refined carbs and generally processed foods in, my weight immediately goes up.
Another thing I've learned to appreciate about physical activity is the feedback it provides. Calisthenics like hand stands, pushups, pullups, all give direct feedback on your power:weight ratio. It's a lot more impactful to only be able to do 80 pushups when last week you were doing 100 every day, than see your weight increased by 10lbs on a bathroom scale. This feedback, for me, plays a more significant role in maintaining my weight through diet via exercise than any direct calorie burning.
The way this article is written is very off-putting.
For instance, "We run around chasing our kids to eat cookies and drink juice, and then wonder why we have a childhood obesity crisis. Good job, everybody, good job."
I am not sure if I understand this: "The median daily intake duration (the amount of time people spent eating) was 14.75 hours per day. That is, if you started eating breakfast at 8am, you didn’t, on average, stop eating until 10:45pm."
I certainly spend may be 1 hour eating everyday including breakfast, lunch and dinner.
Calorie restriction is probably the most important aspect of short term fasting of the sort achieved by eating only in some parts of the day.
Animal studies show that isocaloric intermittent fasting, altering eating schedules, to e.g. alternate day, while still ingesting the same amount of calories, do have benefits. Those benefits hit many of the same areas of metabolism as calorie restriction, but are still significantly different in their overall operation. They are also not as effective at extending life.
Time spent being hungry might be a good metric, but even that is overly simplistic. Grehlin has all sorts of regulatory connections throughout metabolism, but you can't point to any one thing. All of these dietary changes, less calories or more hunger, cause sweeping changes throughout metabolism that are not well understood as a whole. Cause and effect and which parts are important versus not is very much open for debate for any part of this system.
Further, fasting (or fasting mimicking) for longer periods is clearly a different beast from just rescheduling a few meals. In humans fasting for 72 hours or more results in very different outcomes for immune health than anything less than 72 hours. The longer fast kills up to a third of the immune system, which then repopulates when the individual starts eating again, and thus has very beneficial effects in people whose immune system is damaged or dysfunctional in some way (e.g. as the results of chemotherapy).
Similarly these longer fasts produce changes to insulin metabolism that last for months after the fasting is done, which is not the case for fasting in the rearranging a few meals sense.
The studies you mention results of (like the 30% immune system culling in a 4-5 day fast) have only been published for mice so far afaik, but they're currently doing human studies.
Also worth noting that one of the points Valter Longo makes quite strongly in these podcasts is that refeeding after the fast is at least as important as the fast itself.
I may have misunderstood, but the article stated the following:
‘The two arms of the study were eating between 8am and 8pm, and the eTRF strategy of eating between 8am and 2pm, but remember, both groups ate three meals per day of the same foods.’
So it's not like the time restricted people took in less calories. Both groups consumed the same total amount of calories.
i've been fasting 15-16 hours a day everyday for the last 6 years and it's certainly helped me keep my weight about 10 lbs lower than I would have with just dieting. Before that I always subscribed to 3-5 meals a day hypothesis. Once I switched over to fasting 16 hours, I noticed the effect immediately, by losing 10 lbs in 2 months and have kept it off ever since.
The volume of ever-changing and contradictory advice about dieting is maddening. The only dieting advice I truly accept these days is the First Law of Thermodynamics. In context of dieting, you could state this as, eat less (calories) or exercise more (joules) or both, and you will lose weight. Absolutely guaranteed by a fundamental law of physics. Yes, it's very hard to follow this rule, but for me at least a simple rule that is guaranteed to work is much better that complex rules and theories that inevitably turn out to be nuanced, dependent on particular genetics or environment, or plain wrong.
I think everyone knows that "works" on paper. But people are looking for solutions that fit their lifestyle, including human imperfections like the lack of willpower.
I have been doing IF for a month or two now. Hard to really quantify it's effects since I've been eating much better and going to the gym during that same time period. Either way I think it's useful if only as a way to make eating at a calorie deficit easier. My biggest gripe is that it's basically impossible to have a social nightlife on the weekends if you can't eat or drink after 8pm
If time-restricted eating is having that big of an impact on your life, adapt to it. Eat lunch later on the following days after going out, or - and stop me if this is crazy - don't be so strict about it if your friends want to meet up.
I am a time-restricted eater. I use Zero to track my eating windows and make sure I'm not trending in the wrong direction, and that gives me the peace of mind to let up every once in a while.
Just this morning I broke my fast early because I didn't eat enough last night and I was pretty zonked before my workout (beyond the point I thought would be productive). I ate a few dates, recorded it in Zero, and will live to fast another day.
Wondering if you could alternate day fasting on weekends. Social life on Saturday evening and restrict yourself to 500 calories on Sunday. I struggle with this as well. Just curious as to how people manage.
A good cleanout a few times a year is great, but skipping meals and walking around hungry on a regular basis doesn't work for me at all.
3 reasonable sized meals a day with maybe a light snack is just right. No heavy meals, not too much carbs (but not no carbs either). Plenty of vegetables and fruit and protein. Regularly, in small amounts through the day. Keeps me at the right weight, blood sugar not spiked, not off.
Being hungry I have trouble focusing. And mood gets off. I make worse decisions.
Not sure why this fad is so promoted lately, maybe it works for some people but not me and "our ancestors starved" isn't really a good reason to torture oneself for no discernible reason in my opinion.
Many people don't like this but it all boils down to calories in calories out. All human bodies work pretty much the same way with some slight variances due to disease and genetics. Fasting works because it restricts your overall intake.
Many people don't get this, but calories aren't a very reliable measure of available energy. Measuring the caloric content of food is a pretty weird process, and is some kind of "one size fits all" measure of energy which we might be able to extract. The digestive system is not an engine, where you put in fuel, add oxygen, combust and use the energy. The digestive system is more like a mining operation which extracts coal from the bedrock that is your food, and which then throws it over the wall where billions of consumers burn the coal for energy.
That process isn't anywhere near 100% efficient. There is a huge amount of complexity in how food is digested and broken down into protein/sugars/fats. Some people can't even break down certain foods. Even more complexity in how those macronutrients are then dealt with.
Sure, in any system energy in == energy out. But without a way of reliably measuring how much available energy there really is in food for a specific body, there's really no way you can say "calories in, calories out".
A 16 hours fast is so easily achievable that many probably do it without even knowing. If you stop eating by 8PM, and skip breakfast till lunch at noon. That's a 16 hour fast. I've done that basically my entire adult life without even consciously thinking about it. These days I push it out to anywhere from 18-20 hours, and limit my calorie intake from 2pm-8pm. I've been slim my whole life, 175lbs at 6'1. Never get sick, last time I've been to the doctors was easily 20 years ago as a child. Haven't had an antibiotic since grade school. Cardio exercise daily, hiking mountains, no loss of energy.
Am interesting read. IF is supported by much science and I even studied it in a Coursera course on brain hacking. Along with Mediterranean diet and Keto, it's great for the brain and body apparently.
That said, the best advice my Cirque-coach gave me: match food intake with exercise in a given day. So if do a killer workout today, intermittent fasting is not going to give me enough fuel. But if I sit around in meetings/writing 6AM-10PM, fasting for 16h and eating in 8h of that day could work as it'll simply be lessening how much you one eats.
[+] [-] mancerayder|7 years ago|reply
Aside from the individual factors, which include your gender and age and whatever uniqueness about your body that we don't know yet (like effects of gut flora on metabolism), there's the type of exercise you do.
If you do long distance running or cycling, at one extreme, it's obviously a no-go. If you do a short conditioning workout or strength workout right before breaking your fast (if you're lucky enough to have a schedule that allows that), that sounds okay.
There's some speculation that fasting 'resets' the gut flora, or that there's a benefit to 'giving the digestive system a rest', then there's some science around the impact on fasting on circadian rhythm reset benefits, some other science around fasting to 'reset the immune system.'
My personal experience was that I didn't get much benefit in terms of body fat cutting, I didn't notice a performance increase or decrease in the gym (where I do strength training and calisthenics primarily with a bit of cardio). I DID notice I was obsessing over food in the mornings and when 2pm came around, there was a feeling of accomplishment.
I'm not sure it was worth it for me. As for everyone else, the jury's still out. It's just that I'm not convinced it'll be back within my lifetime in this complex area of study.
[+] [-] foldr|7 years ago|reply
This isn't obvious to me. I don't run seriously, but I don't find that fasting has any adverse effect on my performance. If you are talking about running a marathon or something like that, then sure, but hardly anyone is doing exercise that intense multiple times a week, so you could still have fast days.
16 hours really isn't a very long time to go without food. Your body can cope with it fine, even if you're doing quite intense exercise.
[+] [-] parliament32|7 years ago|reply
I always do my runs in the morning, right out of bed, fasted. Your body is very good at storing energy and using it later, I've had no issues (if anything, trying to eat before a run just causes problems for me).
[+] [-] gamblor956|7 years ago|reply
Not obvious at all. My best marathon times followed training cycles where I didn't eat breakfast before long runs (i.e., 13+ miles).
[+] [-] arif_sohaib|7 years ago|reply
[+] [-] wdewind|7 years ago|reply
Besides that the standard: this is done on 8 people over a very small period of time, so it's at best a pilot study anyway.
IF may be a great way for some people to comply to their dietary goals better, but there is still not a single study that shows it actually does anything besides that.
[+] [-] arcturus17|7 years ago|reply
Exactly. I've had pretty bad experiences with a no-breakfast IF. After two or three weeks on the diet, I get insomnia, and I definitely feel more stress. On the latter, I've read that IF raises cortisol levels, so that might be it. That's actually pretty good when you're at low baseline stress levels (it puts you in a state of "positive anxiety"), but when you're stressed from work it can take you over the limit.
Ultimately I stopped it because I'm already at around ~12% BF - I couldn't even say why I was doing it anymore. Three healthy meals a day and regular exercise does it for me.
If this works for people without negative consequences, then all the more power to them. I really like how it goes against the "shove things into your mouth at every waking hour" philosophy, which has become a ridiculous dogma in modern society.
[+] [-] vlasev|7 years ago|reply
If you fast long enough, say 48 hours I think, your body enters a mode of "autophagy", which is highly beneficial. So there's that.
[+] [-] john61|7 years ago|reply
I did a one week Buchinger fasting and did several long distance runs (as I always do) after 2 days fasting. (after switching to cetogen burning) I noticed a small decrease in power, but in no way this was a no go. It was actually fun.
[+] [-] loceng|7 years ago|reply
[+] [-] mancerayder|7 years ago|reply
[+] [-] mtgx|7 years ago|reply
[+] [-] msiyer|7 years ago|reply
Fasting is followed by animals too. When they fall sick they fast. Deliberate fasting in humans is a necessity because humans eat unnatural food.
[+] [-] ccmonnett|7 years ago|reply
Before I began fasting, I found myself saying things like, "Well, this isn't great for me, but it'll be filling for a few hours and then I'll eat something else." With IF that is not an option, and it forced me to more carefully consider whether I was providing my body with the proper fuel for the next X hours.
Similarly, coming out of the fast, I was much more likely to eat nutritionally-valuable foods because I knew that whatever I put in my body it would immediately consume for fuel and I wanted to give it something valuable.
That in itself has led me to rave about IF to anyone who is interested enough to listen. I recommend at least an experiment with it to experience that consideration of nutrition, because I think that will stay with you whether you stick with IF or not.
[+] [-] gremlinsinc|7 years ago|reply
5 weeks ago I was 515. I started a fitness challenge at a CrossFit gym, I workout 4 days a week, I eat Keto, and I (sometimes) eat just one meal a day. I find it really hard, like extremely hard when doing IF to get all my protein in for the day.
I kid you not, because of my stomach size, the keto effects (lower hunger), and only having an hour or two window for food when I stick to IF completely I can't get more than 50 protein, and 600 calories.
This week, I've modified it to fit my body, I've added body fortress protein which 1 scoop in almond milk = 8 carbs, and 60 protein (my daily minimum). I eat this around 11 or noon. Then I try to have my 1 meal at 5pm. Is it IF? Not completely, but I feel for me it works a lot better.
I can probably still get only 600-800 calories a day; example: 2 burgers + 1/4th cup cheese and a dab of mayo and I'm stuffed to capacity, it takes an entire hour to finish this much food, but at my weight that's no biggie, the biggest thing is getting protein so my weight lifting at CrossFit has good results.
I'm no expert on physiology, so if anyone has tips to maximize my progress (I'm about losing more (fat) and gaining more(muscle) as fast as humanly possible).
Physically I feel like a million dollars, depression is mostly gone and anxiety as well. I'm a little obsessed on my diet/exercise regime, not sure that's bad. I started taking Vyvanse for ADHD so that also curbs appetite/hunger and has helped me focus more on my code/work. Last year I had major depression with dark thoughts, this year I feel like a different person, I'm also seeing a therapist for that stuff as of a few months ago.
[+] [-] lawn|7 years ago|reply
Instead a high fat low carb diet where you really minimize carb intake (and obviously avoid all things sugary). You can get the same keto effects if you follow this approach.
This way you can easily eat several times a day and get all protein and calories you need.
Of course you can mix and match IF with this as well.
> I'm a little obsessed on my diet/exercise regime, not sure that's bad.
Be mindful. Obsessions always lie at the edge of turning bad.
Also if you've only done this 5 weeks it's easy to do too much too soon and if a time comes when you can't hold the same extreme tempo you risk a crash. This has happened to me many times. For example I've started a new training form and I train it a lot. But then I don't have the same drive like last week and a miss a single training. Then another one and suddenly I haven't trained for a month.
[+] [-] louprado|7 years ago|reply
It probably took decades to get to your current body weight. Should it not then take at least 5 years to get back to your target weight ? True the caloric math shows you could probably get to 250lbs in a year with a 600-800 a day diet. But can any human actually stick with that diet for more than a month ? If not, you would be better eating 1600-1800 a day if you could stick with it for a year.
As an aside, at times I wonder if our obesity epidemic is in part related to an ever increasing target/acceptable weight. When I was a kid, if you could pinch an inch, you were overweight (I stop drinking calories if I pass the threshold). Even my childhood bathroom scale maxed out at 250 which implied that 250 must be extreme morbid obesity.
I know this is personal, but when you were young did you ever have such thresholds (weight, mobility, etc.) in mind ? Or did it just sneak up on you and by then you were in gaining weight at a surprising rate beyond your control ? No worries if you are too busy to respond. I wish you the best!
[+] [-] unknown|7 years ago|reply
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[+] [-] vlasev|7 years ago|reply
I'm sure you've seen or heard of this case study of the Scottish man who fasted 382 days [pdf]! Of course, he did it under medical supervision. But I think it's an important case of what CAN be accomplished.
[pdf]: https://pmj.bmj.com/content/postgradmedj/49/569/203.full.pdf
[+] [-] squish78|7 years ago|reply
[+] [-] mantenpanther|7 years ago|reply
I can recommend cronometer.com for tracking food, this might be a pain in the beginning, but gives you good insight on what your nutrient intake is. Helped me to create a diet with roughly balanced meals.
[+] [-] logfromblammo|7 years ago|reply
You can eat more protein--likely in drinkable form due to your sleeve--to try to gain more muscle, or you could stay the course to lose the fat first. Since lean muscle mass increases your base metabolism, which increases your fat-burning rate, that's a complex equation that may require calculus to optimize, and your body can always just arbitrarily veto the mathematical results.
[+] [-] koube|7 years ago|reply
[+] [-] jklinger410|7 years ago|reply
I just had someone tell me that the amount of auto accidents increase between 2 and 4pm in the US. This somehow showed that people make poor decisions during that time because of our sleep cycles? I was met with much resistance when I pointed out that there are fundamentally different people driving during 2 and 4pm than 8am or 5-6pm. The numbers don't lie, right? Just how you read them...
Anyway, I'd love to see the science that mindfulness and meditation have dubious benefits. I am such a believer in those practices, I have a hard time understanding the argument that they are not beneficial.
[+] [-] loceng|7 years ago|reply
[+] [-] peterwwillis|7 years ago|reply
The whole point of a diet is to be healthy. You don't need intermittent fasting to be healthy. It seems to just introduce complication for a menial improvement in a few measures of health. I'm sure they work, if you can actually stick to them, but there's a lot simpler diets that will also work.
Exercise three times a week. Eat lots of plants. Keep your fat, protein, and simple carb levels within reasonable limits for your age, height and sex. That's not super complicated to follow, and it can fit into basically any schedule.
[+] [-] tzs|7 years ago|reply
"What I learned about weight loss from spending a day inside a metabolic chamber"
[1] https://www.vox.com/2018/9/4/17486110/metabolism-diet-fast-w...
[+] [-] socalnate1|7 years ago|reply
[+] [-] ngngngng|7 years ago|reply
The problem is made worse because overweight people typically greatly underestimate how much they eat, while underweight people (me most of my life) typically greatly overestimate how much we eat. It's nearly impossible to accurately gauge calorie intake without strict calorie counting.
When talking nutrition with people, I'll often bring up the examine.com piece on "does metabolism vary between two people?"(1) And I am always amazed to find at least one person in any conversation that will flat out deny the information presented there. they are positive that if they ate one single slice of pizza a day and nothing else, they would still be fat.
1: https://examine.com/nutrition/does-metabolism-vary-between-t...
[+] [-] louprado|7 years ago|reply
Personally if I eat dinner after 5PM, I have trouble sleeping.
[1] https://www.ncbi.nlm.nih.gov/pubmed/21950773
[+] [-] rawland|7 years ago|reply
According to the paper these "eight overweight men with prediabetes [...] had a mean BMI of 32.2 ± 4.4 kg/m2" (page 3).
The metabolism of these people is quite different compared to a healthy human. These were sick people. And they received a strictly controlled and monitored diet according to the paper.
Paper mentioned in article: https://www.ncbi.nlm.nih.gov/pubmed/29754952
[+] [-] RobertRoberts|7 years ago|reply
Today I am at a low of 181.2lbs. I haven't been this weight for probably over 12 years.
Last summer I did a month of running 6 days a week (increased distance as I went) + 1 meal a day (strict). And lost .5-.6lbs a day in 30 days. I went from 202 to 187. I gained some of it back by December. I was fluxuating between 192-195.
Then I changed my tactic, did strength exercising for one month, got up to 198, didn't lose weight at all.
Current experiment: I changed two things -
1. I said "it's ok/fine/good to be hungry". I now naturally eat one meal a day, I eat when I want, but I don't fool myself. Sometime I eat only a couple bites of something to ease my stomach.
2. No exercise during this time at all. No running, lifting, pushups, nothing.
I have gone from 198 to 181 from last January to Oct, 2018. (17lbs) Not eating is what makes you lose weight. Being hungry is your body telling you it's eating fat. I even went to a wedding, gained 3 lbs in 3 days, and shed them again 3 days later. (obviously not all of it stuck on me in the first place)
After awhile you get used to being hungry, your diet matches your need and intake. Be hungry, control your weight, it's liberating. I never have to worry again the rest of my life how to manage my weight.
[+] [-] newnewpdro|7 years ago|reply
My experience going from 225lbs to 165lbs and keeping it there for over a decade now +-5lbs suggests there's no need to feel hungry at all, as long as I'm eating the right foods.
I didn't use any exercise, just removed sugars and most refined carbohydrates and processed foods in general. Most the food I eat by volume is raw organic produce. I can eat plain heads of lettuce all day long and I will not gain weight. I eat canned wild sardines, salmon, and sometimes tuna for protein and omega-3s, with the occasional (~weekly) meat binge.
Once my weight stabilized at 165, physical activity became a lot more appealing so I started hiking, running, doing hand stands, pushups, generally being more active and this has given me a more masculine physique but doesn't seem to play much part in maintaining my weight.
Sometimes I experiment by ceasing most physical activity for a week or two, and mostly what happens is I become less sexy looking, the weight is more or less the same with the uniform mostly-produce diet. My mood does deteriorate though.
When I deviate from the diet, usually for social reasons, eating meat more often or letting more refined carbs and generally processed foods in, my weight immediately goes up.
Another thing I've learned to appreciate about physical activity is the feedback it provides. Calisthenics like hand stands, pushups, pullups, all give direct feedback on your power:weight ratio. It's a lot more impactful to only be able to do 80 pushups when last week you were doing 100 every day, than see your weight increased by 10lbs on a bathroom scale. This feedback, for me, plays a more significant role in maintaining my weight through diet via exercise than any direct calorie burning.
[+] [-] fermienrico|7 years ago|reply
For instance, "We run around chasing our kids to eat cookies and drink juice, and then wonder why we have a childhood obesity crisis. Good job, everybody, good job."
I am not sure if I understand this: "The median daily intake duration (the amount of time people spent eating) was 14.75 hours per day. That is, if you started eating breakfast at 8am, you didn’t, on average, stop eating until 10:45pm."
I certainly spend may be 1 hour eating everyday including breakfast, lunch and dinner.
[+] [-] reasonattlm|7 years ago|reply
Animal studies show that isocaloric intermittent fasting, altering eating schedules, to e.g. alternate day, while still ingesting the same amount of calories, do have benefits. Those benefits hit many of the same areas of metabolism as calorie restriction, but are still significantly different in their overall operation. They are also not as effective at extending life.
Time spent being hungry might be a good metric, but even that is overly simplistic. Grehlin has all sorts of regulatory connections throughout metabolism, but you can't point to any one thing. All of these dietary changes, less calories or more hunger, cause sweeping changes throughout metabolism that are not well understood as a whole. Cause and effect and which parts are important versus not is very much open for debate for any part of this system.
Further, fasting (or fasting mimicking) for longer periods is clearly a different beast from just rescheduling a few meals. In humans fasting for 72 hours or more results in very different outcomes for immune health than anything less than 72 hours. The longer fast kills up to a third of the immune system, which then repopulates when the individual starts eating again, and thus has very beneficial effects in people whose immune system is damaged or dysfunctional in some way (e.g. as the results of chemotherapy).
Similarly these longer fasts produce changes to insulin metabolism that last for months after the fasting is done, which is not the case for fasting in the rearranging a few meals sense.
[+] [-] roganartu|7 years ago|reply
The studies you mention results of (like the 30% immune system culling in a 4-5 day fast) have only been published for mice so far afaik, but they're currently doing human studies.
Also worth noting that one of the points Valter Longo makes quite strongly in these podcasts is that refeeding after the fast is at least as important as the fast itself.
[+] [-] onewhonknocks|7 years ago|reply
‘The two arms of the study were eating between 8am and 8pm, and the eTRF strategy of eating between 8am and 2pm, but remember, both groups ate three meals per day of the same foods.’
So it's not like the time restricted people took in less calories. Both groups consumed the same total amount of calories.
Please correct me if I'm wrong.
[+] [-] megaman8|7 years ago|reply
[+] [-] mysterypie|7 years ago|reply
[+] [-] ionforce|7 years ago|reply
[+] [-] southphillyman|7 years ago|reply
[+] [-] ccmonnett|7 years ago|reply
I am a time-restricted eater. I use Zero to track my eating windows and make sure I'm not trending in the wrong direction, and that gives me the peace of mind to let up every once in a while.
Just this morning I broke my fast early because I didn't eat enough last night and I was pretty zonked before my workout (beyond the point I thought would be productive). I ate a few dates, recorded it in Zero, and will live to fast another day.
[+] [-] throwaway82729|7 years ago|reply
[+] [-] gdsdfe|7 years ago|reply
[+] [-] mythrwy|7 years ago|reply
3 reasonable sized meals a day with maybe a light snack is just right. No heavy meals, not too much carbs (but not no carbs either). Plenty of vegetables and fruit and protein. Regularly, in small amounts through the day. Keeps me at the right weight, blood sugar not spiked, not off.
Being hungry I have trouble focusing. And mood gets off. I make worse decisions.
Not sure why this fad is so promoted lately, maybe it works for some people but not me and "our ancestors starved" isn't really a good reason to torture oneself for no discernible reason in my opinion.
[+] [-] jcoffland|7 years ago|reply
[+] [-] Tharkun|7 years ago|reply
That process isn't anywhere near 100% efficient. There is a huge amount of complexity in how food is digested and broken down into protein/sugars/fats. Some people can't even break down certain foods. Even more complexity in how those macronutrients are then dealt with.
Sure, in any system energy in == energy out. But without a way of reliably measuring how much available energy there really is in food for a specific body, there's really no way you can say "calories in, calories out".
[+] [-] thebeefytaco|7 years ago|reply
Not true. Calories are a very crude metric of metabolic energy.
Wood (and anything else that burns) has a bunch of calories, yet we cannot process it as energy.
[+] [-] overcast|7 years ago|reply
[+] [-] octygen|7 years ago|reply
That said, the best advice my Cirque-coach gave me: match food intake with exercise in a given day. So if do a killer workout today, intermittent fasting is not going to give me enough fuel. But if I sit around in meetings/writing 6AM-10PM, fasting for 16h and eating in 8h of that day could work as it'll simply be lessening how much you one eats.