I’m interested to hear what the overall take on this from fasters who understand the hormonal impact of fasting on the body.
Dr. Fung rarely qualifies this statement and uses black and white terminology such as “the CICO theory has been debunked,” and “CICO doesn’t work.”
Obviously creating enough of a caloric deficit sheds pounds and if you eat enough of a caloric surplus you can overshadow the hormonal benefits of fasting.
But Dr Fung claims with enough of an insulin imbalance, someone on a 700-calorie diet could gain weight.
Thoughts?
If you don’t know who/what I’m talking about:
Dr Fung discusses the failure of the “Eat Less, Move More” approach to weight loss
I’ve pondered over this a lot and was able to get what he means by reading up more on this.
The idea he is against is the fact that if you eat in a deficit, but are eating in an expanded window which covers most of the day, you will not deplete fat that’s stored in your body. This is because in the presence of insulin the process of burning fat stored in the body does not take place . For that matter increased insulin levels also encourage storage of fat, which is only going to make the problem worse. The insulin factor itself proces that calories in calories out does not work for weight loss.
The obvious alternative is basically a calorie deficit, which I personally feel CICO is a subset of. With a reduction of calories below a certain level you tend to lose weight, but reach a plateau soon enough. This is explained by the body’s ability to adjust to different levels of calorie inputs.
Mind you, CICO and Calorie deficit discussed above are without any restrictions on when the calories are being consumed. With this, you’re basically limiting additional storage of fat, but as far as you don’t have windows where there’s no insulin in your blood, stored glycogen and stored fat will not be depleted.
If you read his book and watch his talks, he does support monitoring calories on the regular in addition to fasting. And in my personal experience as well this is why people find sustainable sucess with fasting. The reduced calories ensure you aren’t storing additional fat and the fasting window helps in breaking down the stored glycogen and then the stored fat.
Dr Fung - Solving the two compartment problem
Dr. Fung argues the hormonal theory of obesity and diabetes, not caloric. CICO can work, and can work for some peoples physiology. He argues that in a widespread mass population basis, it doesn’t work. He argues insulin is the main hormone to keep low, and the best way to keep low is fasting. He argues low carb works well, depends on your own degree of insulin resistance. Of every physician I have every listened too, he makes the most sense. Don’t let 1 podcast / lecture / etc throw off the way his insight to diabetes and obesity pathophysiology. The hardest part with his method is support, good support is hard.
I don’t think there’s any question that in and of itself, CICO doesn’t work.
There’s plenty of research to show that a starvation diet (low calorie, high carb) can keep your insulin elevated and your stored fat inaccessible; to the point where obese mice will break down and consume their vital organs, and die of starvation — while preserving their ample fat stores and remaining obese.
CICO only ever worked in a short term because it would soon become too hungry to even think straight. Like, a week of 1200 calories per day was the absolute max and then I’d pretty much lose all focus and eat whatever I craved. Sure, I lost 5 lbs of water weight but then gained back the 5 lbs of water weight again.
But steady IF worked much more consistently and as long as it was primarily low carb, high protein and fat, I did well. No nagging, building hunger. No flashpoint where I need to eat everything. I don’t count calories at all and just learned to listen to my body that is was full. I’ve lost the majority of my 110 lb loss with IF, and periods of longer term fasting.
Cico will always work. But sustainability is what he questions. After all fasting is just one type of CICO. When you fast your Calorie in is zero from carb or protein and your Calorie out will come from your own body fat. What he suggested is if you do Cico everyday like cutting calories from 2000 to 1500 is not gonna help you to sustain the weight loss because your metabolism adapts and just gonna consume less. The really problem is your body will always consume carb calories first which means it never burns body fat. Fasting is essentially giving your body a break from carbs and protein and learn to burn the fat in your body.
Well if there’s someone out there who knows his shit that’d be JF. Personally, I’ve never seen CICO as anything other than a diet scheme, not a lifestyle. I know it can work, but I think IF works better in every way. I’ve been telling anyone who’d listen as far back as the late 90s (used to work at a gym) to stop counting calories and eat whole foods. I’ve never seen anyone calorie counting who kept the weight off. Anyways, I’m totally with Fung on this.
Considering the laws of physics are real and starvation mode is a myth I’ll have to say he’s straight up ignorant, wilfully or not. That’s just a completely incorrect stance. Even if you were in constant ketosis but ate at maintenance or more I can guarantee there would be no weight loss.
I think CICO works if you’re like 5 to 10 pounds over your ideal weight and have no other health problems like diabetes. But a person with years in the obesity range,will probably need another approach where hormones play a bigger role.
I’ve done fasting on a regular diet and on keto and fasting on keto is like fasting on easy mode. When I cut out carbs it completely changed my hunger signals and I could easily do 18:6 and 20:4 fasts daily.
I went off keto after doing it for 4 months in October (and losing 30 pounds) and I’m back on it now to finish losing the last 20 pounds.
As soon as I started eating carbs again my hunger signals felt so intense! It’s crazy how different it is for me between keto and regular macros.
Hmmm I call BS. Eating too much too often creates weight gain. Like, duh? Being fat/obese/morbidly obese creates insulin resistance which piles on more weight. OMAD causes me to be at a caloric deficit (not on purpose and I need to stop counting OMAD calories lol.) but AFAIK fasting caloric deficits are safer than spacing the cals out through the day and spiking blood sugar and being more hungry.
I’m practically not hungry at all except maybe after 23 hours. 🤔
I agree with him. All of the information he’s presented in his books is backed by peer-reviewed studies, and the citations are there. For quite awhile I tracked carb intake to make sure I was at/under 20 net grams a day. The app, by default, kept track of calories, as well. I don’t work out at all, and I was eating between 1800-2300 (sometimes more) calories a day, and I dropped weight consistently - and have kept it off for. All calories are not created equal. I won’t get into it with anyone, people will believe what they want. Whenever I see anything about calorie deficit, I just scroll on by.
It’s been his experience with his clients so he’s just talking from that perspective. The people that come to him have struggled with weight loss using cico and he has developed protocols that work for those people.
Fung is right. CICO only works in short term. In Ling term it always dail.
What Fung is explaining is the human body physiology. So CICO has left me over weight for forty years.
I only lost 100 pounds following Fung and still keeping it off.
So yes , Jason Fung is DAMN RIGHT.
Several thoughts on this. Mostly I agree, but I agree with it in the sense of applying it as universal weight loss advice for everyone doesn’t work. The key point is for every study that shows some diet or fitness approach works there are always members of that study who do not respond to the stimulus the same way. We’re all very different. The one thing that seems to be very clear is that the calculus of weight loss is not a CICO one. But it starts there.
I don’t know why or how this gets so misinterpreted. He is not saying eat 3000 calories during your eating window and lose weight. He is saying that eating all day and restricting calories will never give your body the ability to reset between food intake. You will constantly be spiking your insulin. It’s simple and it does make sense.
It works if you work it. Like everything else.
I think what people really mean is “I don’t want to eat less forever” when they say “diets don’t work” - well you’ve been eating too much forever so it shouldn’t come as a surprise but it always does (and did to me as well).
It’s about giving your body the time to use them before eating again, along with the quality of food. I am 5’4” and 145lbs. I don’t exercise other than walking the dog. I can eat 3000 calories a day, in two meals, and maintain my weight. I eat unprocessed foods, lots of meats and healthy fats and lower carb veggies. My body is more efficient because I keep my glycogen stores down, and glucose low for 16-18 hrs a day. I think that but also the food I eat my body actually utilizes instead of trying to store it or remove it.
Definitely his most scammy take on weight loss. He could easily have said that CICO if strictly adhered to will allow for weight loss, but is more difficult and less successful to stick with than fasting. There, now he’s covered all bases.
But instead he’s taking a stance that goes against basic biology.
With that said, fasting is king and the best method for me to keep weight in check.
He does qualify his statements with the fact that you need to be in an energy deficit and that binge eating lots of food in your eating window can nullify the effects of fasting.
Energy deficit is not necessarily the same as counting calories, but can be achieved with eating good homecooked food as little refined as possible with enough nutrients (esp protein, fiber and fat) to keep you fuller for longer. A key is to eat till you’re pleasantly full. Dr Giles Yeo has some good lectures on youtube on how to eat to kerp you full and why a calorie isn’t a calorie (beyond it being a unit of measuring energy). Where the calories come from matters.
He’s right. If it was as simple as a calorie deficit for everyone we wouldn’t have an obesity epidemic or a 90%+ failure rate at maintaining weight loss. Hormone imbalance drives people to overeat, drives excessive fat storage, and people eat crap food and live sedentary lifestyles that cause hormone imbalance.
I agree 100%. Because not all calories are digested and reach your blood.
If you set a block of wood on fire that would release a lot of heat (and a calorie is a unit of heat). But if you ate that block of wood would your body receive the same number of calories? No, of course not. You’d shit out most of them without them ever digesting them, so they’d never reach your bloodstream.
I find this very reassuring that I am not alone or crazy!
I consume 1000-1200 calories a day max, if I’m stressed out or tired I’ll still gain weight. I work a physical job and play sports. My best friend of 30 years is convinced the laws of thermodynamics do not apply to me. Every diet I have tried I have been accused of cheating or lying in my food logs, the only exception to this was the Dr.B diet which is a ketosis fast. I am glad I have found fasting, but angry that I have spent years overweight and hungry listening to professionals and doctors telling me to eat 1600 cal, exercise more, eat lots of small meals, and avoid fat.
How many people do you know that count calories (CICO) and have consistently maintained their weight for years? I don’t know anyone personally, typically people get sick of trying to micromanage calories after a few months, it’s much easier to change meal timing and composition instead of busting out the food scale and looking up calorie values.
I have been reading this book called “The End of Craving.” I agree that CICO doesn’t work, but only because (as outlined in the aforementioned book) our brain is often confused by what we eat.
We eat and drink things that have sweetness, but no calories. We eat things that taste like fat, but have fewer calories than fat. Our brain ends up confused because it becomes uncertain, just like a broken gas gauge on an automobile.
It’s a fascinating read.
Of course at it’s most basic form CICO works – it’s literally a law (of thermodynamics),
When he’s saying it doesn’t work what he’s really doing is dumbing it down for the masses.
eg
Most will put their height, weight, age etc into an activity calculator to get their “calories out” then just eat less than that so calories out is more than calories in.
Unfortunately it’s that calories out part of the equation that is much, much more complicated than that. There are all kinds of hormonal things the body can do to mess with it, as well as other things like lowering body temp, lowering the amount the body fidgets, subconsciously changing respiration rate, etc.
If one could perfectly account for those things, then the law holds. In real life, one certainly can’t properly account for those things and it seems as if CICO doesn’t work.
It becomes much easier when one helps the body a bit by keeping insulin low (among other things).
He is right in that CICO will only harm the metabolism and end up with rebound weight gain. Hormones are the managers of weight and he has demonstrated how true that statement is. You can reduce calories and eat based on hormonal principles and achieve the best success.
I understand that he doesn’t necessarily dismiss cico but instead provides other alternatives but I think people for whom cico doesn’t work are lazy people with little to no will power.
Yes, you should move more and eat less, no, you don’t need to have your hand held and see a shrink, you just need to stop stuffing your face with shit. But of course this message doesn’t get across very well
It doesn’t work for people with metabolic syndrome and insulin insensitive people when you allow a threshold of carbs greater than 25 or so. These people need CICO, in addition to small feeding windows, and low carbs. So the traditional CICO where if it fits your macros doesn’t work for most obese individuals.