5:2 has certainly worked for me – I started fasting on a whim at the beginning of the Corona closedown, and it took 10 kgs off of me. I feel hungry in the morning around the time I would normally eat breakfast, but after that there is no more discomfort, and I go through my day, including exercise, as I normally would.
> Others like the 5:2 diet (in which dieters eat a normal amount of food for five days before two days of eating only 25% of their usual calorie intake) focus more on the amount of food consumed, rather than the time between meals.
All of the recent research has made it obvious that as long as we are in a post-absorptive state (12 hours after eating), every hour of fasting racks up the same benefits, regardless of whether it's a prolonged or intermittent fast. Most intermittent plans will allow for 3-4 post-absorptive hours per day, and after a month, the benefits are basically identical to that of someone who fasts for 5 consecutive days per month. Both result in ~120 hours of post-absorption.
Autophagy seems to be an on-off switch instead of a spectrum of effectiveness, so an hour is an hour, even if you're doing it "wrong."
I do fast now and then, I did it more strictly in the past, but I am naturally pretty skinny so I don't want to loose weight. These days I can do 18 hours without too much effort, but it doesn't feel as beneficial as when I would do 36 hours (admittedly with 600 calories, based loosely around teh 5-2 diet). There are more benefits than just autophagy.
The main benefit of IF which isn't mentioned in the article (and hasn't yet been mentioned in the thread) is regaining insulin sensitivity. Losing insulin sensitivity is what leads to a low-functioning liver and causes the body to start storing excess sugar as fat.
Correct. Was waiting to see this response. I do IF to try to prevent the diabetes found in my family from ever triggering in me.
This is so important for Americans because the majority of us are certainly consuming too much sugar and other foods with huge insulin responses and many are put at needless risk of diabetes as a result.
I have been on and off on the intermittent fasting bandwagon since 2019. Mostly time restricted feeding. 18+ hours works much better for me than 16 hours.
I lost some fat, I got rid of my high blood pressure (no more medication - after 17 years no less) and I am a lot more mindful about what I eat. Once you only have limited opportunities to eat in a day, you will start caring more; each meal is precious.
I also learnt a few tricks. If you are really, really hungry, even a single hazelnut or two is enough to put your stomach to rest again. Many fasters recommend clear bone broth, especially for longer fasting periods. It is very soothing.
Caffeine is a two-sided sword. It will suppress your hunger, but it will also make you way more jittery. I am very careful about caffeine now, I drink decaf only on "normal" days and will only have caffeinated drinks when traveling.
Diet sodas are a problem for me. They upset my empty stomach very reliably and sometimes lead to heartburn. No longer drinking them.
Research is showing that most (all) of the benefits related to IF are due to fat loss. As long as calories in - calories out are equated, there is no statistically significant difference between a regular caloric deficit and IF. This isn't to say IF is bad, adherence is the most important part of any diet. If it works for you great, but there's not any evidence that it's superior to any other form of diet in terms of bio markers.
There's really not enough evidence for longer multi day (5+) fasts at this point either, but it's a promising avenue of research.
I can't read the full text of one of the articles, just the abstract. Both studies focus on weight loss of obese and overweight people. 35% were diabetics, and 70% had high cholesterol.
You attribute the benefits to a specific mechanism, fat loss, but what the summaries say is that IF is effective for weight loss and is similar to tradition calorie reduction diets without suggesting the causal chain. You've attributed a mechanism whereas the abstracts didn't.
"In conclusion, IER improves anthropometric outcomes and intermediate disease markers when compared to a usual diet. The effects of IER on weight loss are similar to weight loss achieved by CER."
and
"Conclusions: Intermittent energy restriction is an effective alternative diet strategy for weight loss and blood pressure control and is comparable to CER in overweight and obese patients with hypertension. "
I'm at my target weight (5'11@160 lbs / 1.8m@72.5kg), so the data from obese/overweight people doesn't apply to me. I'm interested in possible health benefits of increased insulin sensitivity and autophagy, which it seems like these didn't really investigate.
I think you're missing the point. A diet's success depends on how hungry it makes you feel. A diet with a 100 calories per day deficit where you're never hungry is (obviously) superior to a diet with a 100 calories per day deficit where you're always hungry. The advantage of IF is to reduce hunger.
This ignores the (admittedly under-researched) aspect of autophagy after 12-14 hours of fasting.
It's also not clear from your sources whether there actually was a caloric equivalence in the diets. Dietary patterns can significantly affect base metabolic rate, which is the biggest problem with just caloric restriction, where your base metabolic rate is lowered. This means you eventually stop losing weight while also being restricted to consume fewer calories. It's a vicious cycle.
Anecdotally, you can lose weight with just restricting your feeding window to 8 hours while eating "normally". Perhaps that inadvertently results in caloric restriction, but it feels different. As such, it's more sustainable.
I have been only having one meal (dinner at around 7p) for more than 3 years now. I do have a cup of black coffee in the morning and smoke a moderate amount of nicotine through the day (vape, 5%). In a very short time you stop getting hungry until the evening.
Speaking for myself, one of the main benefits of fasting is that I start to feel like I have more control over my eating. When I'm fasting it starts to become easier to say "No" to cravings and impulses to wander into the kitchen and graze.
Same here. I struggle with portion control. I can pig out like its no one business.
IF provides me a structure that I can help control my eating schedule, tied in with a food subscription (https://chefgood.com.au/), it means I'm seeing weight loss and structure eating benefit my health.
Does anyone have any real research showing IF having benefits beyond what one achieves through healthy eating and general weight loss in humans? Seems like every paper i see is either in animals or cell cultures, or does not have a proper control group.
Back when I had looked into the literature, the consensus seemed to be that it was not more effectice than CR for weight loss.
If that's still the case, it would depend on what you find easier to maintain over long periods of time. For some people, eating healthy/less and or tracking calories is a lot harder than just eating one big meal a day.
Anecdotally fasting and calorie restriction seems to give me short-term energy in exchange for the long-term need to replenish the energy. After several hours without eating i feel really good, even doing intense exercise. I continue to feel good and energetic sometimes even after a full day. But fasting too long or losing too much weight and I start getting really tired. And then when I eat it makes me even more tired because eating in general makes me kind of lethargic.
Sounds like you are just running out of carbs. Keep going and your body will start burning fat instead of carbs for energy and your energy levels will return. Eating less sugar and carbs in your normal diet should greatly lesson those symptoms.
Does anyone know if drinking coffee black stops autophagy and "technically" breaks a fast? I seem to recall reading that a while ago, but can't find the source.
Depends on what you're trying to accomplish with the fast. If the goal is gut rest, you're probably breaking the fast to some extent.
As for autophagy, as far as I know there are no good biomarkers to determine autophagy levels, so it's hard to say whether black coffee stops autophagy, or even whether you've entered a state of increased autophagy as a result of the fast, regardless of length or methodology. It'd be great to have some, though.
I started IF about two years ago. I gradually, over a very long period worked down to one meal a day. It wasn’t hard, because it was gradual. I didn’t lose weight (but I wasn’t overweight to begin with), but I have leaner stomach and I gained muscle and strength. I’ve never felt better in my life. The first improvement I noticed was mental clarity.
It is embarrassing that the BBC article gets all its information from only one “expert”, who doesn’t seem expert at all. So shallow. For me, the best source of solid evidence-based information about IF was Jason Fung’s Obesity Code.
It's pretty easy to do if you work your way up to it, if you eat normal it would make you sick at first but you would adjust quicker than you'd tbink. It's not really even unusual anymore, a lot of people eat that much for every meal.
Just slowly eat more and more food to expand the size of your stomach, not really a trick to it or anything. I've heard the professional hot dog eaters drink large amounts of water with large meals to expand their stomachs though if you want to get there fast I guess. An actual step by step would probably just doing two 1k meals then shifting over 200 calories at a time if you are still feeling bloated.
While not seriously overweight I had maybe an extra 10-15 pounds last year. Started just eating breakfast, a really fatty breakfast with bacon, ham, eggs, lard tortillas (they are the best) and salsa. Maybe 1500+ calories, I don't know.
Then I simply wasn't hungry the rest of the day. The intermittent fasts were seldom pure, I might have a few crackers or fruit or something if hungry and would occasionally eat a light lunch or supper as the occasion demanded.
Lost the extra weight in like 2 months. Jeans fit well again and belt was back to the first hole. I didn't do any extra exercise, just the usual walks and yard work. It was no kind of suffering or struggle at all so I've been mostly sticking with it.
It's also nice to only worry about essentially one meal a day.
38 comments
[ 5.0 ms ] story [ 90.1 ms ] thread> Others like the 5:2 diet (in which dieters eat a normal amount of food for five days before two days of eating only 25% of their usual calorie intake) focus more on the amount of food consumed, rather than the time between meals.
FTA: It’s called the 5:2 diet because five days of the week are normal eating days, while the other two restrict calories to 500–600 per day.
Autophagy seems to be an on-off switch instead of a spectrum of effectiveness, so an hour is an hour, even if you're doing it "wrong."
This is some really useful info, I always thought it was a spectrum. would you please be able to point to some papers on this?
I do fast now and then, I did it more strictly in the past, but I am naturally pretty skinny so I don't want to loose weight. These days I can do 18 hours without too much effort, but it doesn't feel as beneficial as when I would do 36 hours (admittedly with 600 calories, based loosely around teh 5-2 diet). There are more benefits than just autophagy.
This is so important for Americans because the majority of us are certainly consuming too much sugar and other foods with huge insulin responses and many are put at needless risk of diabetes as a result.
I lost some fat, I got rid of my high blood pressure (no more medication - after 17 years no less) and I am a lot more mindful about what I eat. Once you only have limited opportunities to eat in a day, you will start caring more; each meal is precious.
I also learnt a few tricks. If you are really, really hungry, even a single hazelnut or two is enough to put your stomach to rest again. Many fasters recommend clear bone broth, especially for longer fasting periods. It is very soothing.
Caffeine is a two-sided sword. It will suppress your hunger, but it will also make you way more jittery. I am very careful about caffeine now, I drink decaf only on "normal" days and will only have caffeinated drinks when traveling.
Diet sodas are a problem for me. They upset my empty stomach very reliably and sometimes lead to heartburn. No longer drinking them.
look into the FODMAP stuff that monash uni is doing.. https://www.monashfodmap.com/
There's really not enough evidence for longer multi day (5+) fasts at this point either, but it's a promising avenue of research.
EDIT: https://pubmed.ncbi.nlm.nih.gov/32363896/ https://pubmed.ncbi.nlm.nih.gov/34733895/
You attribute the benefits to a specific mechanism, fat loss, but what the summaries say is that IF is effective for weight loss and is similar to tradition calorie reduction diets without suggesting the causal chain. You've attributed a mechanism whereas the abstracts didn't.
"In conclusion, IER improves anthropometric outcomes and intermediate disease markers when compared to a usual diet. The effects of IER on weight loss are similar to weight loss achieved by CER."
and
"Conclusions: Intermittent energy restriction is an effective alternative diet strategy for weight loss and blood pressure control and is comparable to CER in overweight and obese patients with hypertension. "
I'm at my target weight (5'11@160 lbs / 1.8m@72.5kg), so the data from obese/overweight people doesn't apply to me. I'm interested in possible health benefits of increased insulin sensitivity and autophagy, which it seems like these didn't really investigate.
It's also not clear from your sources whether there actually was a caloric equivalence in the diets. Dietary patterns can significantly affect base metabolic rate, which is the biggest problem with just caloric restriction, where your base metabolic rate is lowered. This means you eventually stop losing weight while also being restricted to consume fewer calories. It's a vicious cycle.
Anecdotally, you can lose weight with just restricting your feeding window to 8 hours while eating "normally". Perhaps that inadvertently results in caloric restriction, but it feels different. As such, it's more sustainable.
Replace breakfast with a black coffee, hydrate well through lunch, and eat a huge dinner starting with salad.
IF provides me a structure that I can help control my eating schedule, tied in with a food subscription (https://chefgood.com.au/), it means I'm seeing weight loss and structure eating benefit my health.
If that's still the case, it would depend on what you find easier to maintain over long periods of time. For some people, eating healthy/less and or tracking calories is a lot harder than just eating one big meal a day.
As for autophagy, as far as I know there are no good biomarkers to determine autophagy levels, so it's hard to say whether black coffee stops autophagy, or even whether you've entered a state of increased autophagy as a result of the fast, regardless of length or methodology. It'd be great to have some, though.
It is embarrassing that the BBC article gets all its information from only one “expert”, who doesn’t seem expert at all. So shallow. For me, the best source of solid evidence-based information about IF was Jason Fung’s Obesity Code.
Then I simply wasn't hungry the rest of the day. The intermittent fasts were seldom pure, I might have a few crackers or fruit or something if hungry and would occasionally eat a light lunch or supper as the occasion demanded.
Lost the extra weight in like 2 months. Jeans fit well again and belt was back to the first hole. I didn't do any extra exercise, just the usual walks and yard work. It was no kind of suffering or struggle at all so I've been mostly sticking with it.
It's also nice to only worry about essentially one meal a day.