Excellent post – thank you for breaking down the Cochrane review so clearly!
I turn to IF periodically, not for weight loss, but to help "reset" when I've started to eat too much junk. It's a psychological effect: Eating windows help me be more mindful about what I'm eating.
You mentioned that two book agents have turned down your idea that all diets are about the same for one's health. I wonder if you added (or would want to add) that each diet may have micro-benefits that depend on the individual. For instance, I imagine that IF would be no better or worse than any other diet if I were aiming for weight loss. But as for changing the content of what I eat, IF works better than anything else. I don't need a chart describing the Mediterranean diet. I need something that pushes me to think about what I eat next.
Your overall message certainly makes sense, no one diet works like magic for everyone. My quibble about the conclusion that fasting is about the same as any other calorie restriction Model is that the analysis lumps all the studies together and calls it intermittent fasting.
Fasting is just one of the methods I teach in my clinic, but I do suggest it frequently. But of course there are myriad models of IF and I strongly feel that each model needs to be evaluated separately. In my mind, for instance, the models that utilize calorie restriction to 500 calories on "fasting" days isn't fasting at all! That's just calorie restriction. Also, most studies of more traditional models focus on a 16 hour fasting window which, in my clinical experience, I rarely find works well. Jump up to a 20 hour window (with NO calorie restriction during the eating window) and success jumps up substantially. Of course clinical experience can not take the place of controlled trials, but lumping all of these "fasting" trials together even when they aren't actually having patients fast just muddies the water.
Thanks for a nice piece! I agree with the overall message, but I have my doubts as to whether there is actually much evidence to support this claim:
“If you’ve got what scientists call excess adiposity—too much fat—losing weight is a good idea for your health…”
It also must depend a whole lot on the *how*: Calorie restriction, weight loss meds or cutting off limbs? And how exactly do you measure and define the outcome, health?
I’m not just being pedantic: please guide me to relevant evidence or do a piece on this topic!
What I have heard from researchers in the UK is that the point of intermittent fasting has zero to do with calories. It's all about creating a healthy gut microbiome. Which in turn enhances our immune system and the gut/brain connection, etc. It's about letting the microbiome process all the food it needs to process, repair any of the gut lining that goes along with day to day wear, and then rest. Before we start to pummel it again with more food to process. It's about a healthy microbiome. Not about calorie restriction.
I have yet to see strong evidence - or even moderately convincing evidence - for any of the secondary proposed effects of intermittent fasting.
Moreover, these effects do not appear to show up in any meaningful way clinically in trials of the diet. If the diet does do something to the gut microbiome, it doesn't appear to impact any of the health metrics that we've so far tracked (which is all of the most important ones).
Correct me if I’m mistaken, but I believe your premise is, “most diets are about the same for your health.” However, your argument — and your conclusion — focus primarily on diets and losing weight.
I’ve always believed in the idea of calories in/calories out. I’m more interested in the effects of intermittent fasting versus other diets on health markers beyond those brought about by weight loss alone.
Very interesting thanks! Not sure if IF helps longevity and agree it’s no silver bullet for weight loss… but I’ve been dabbling with a 5-7hr eating window for a few years now and personally I find the increased metabolic flexibility is really neat! I can easily run 10-13mi in a 14-16hr fasted state which blows my mind.. I can go skiing for 4-5hrs on an empty stomach (no breakfast) without issue. It’s so cool not to stress about sugar on a run or snacks on the ski slope and not fear “bonking”. This has only been the case last few years while on IF. My last food for the day is usually 2-4p (unless for social reasons) and I never wake up (early bird) hungry. It’s been a fun experiment and I intend to keep it up.
Is there any evidence to support the long term (beyond a year or two) efficacy of *any* lifestyle modification plan for weight loss? My understanding that the only effective treatments (to date) for obesity are bariatric surgery and GLP-1 agonists.
Sort of what I expected and thanks for clarifying it. Do you think you will be doing something on the benefits of ice water immersion and its supposed health benefits? To me it is in the same boat as IF. I don't have anything against either but am dubious about the benefits.
Full disclosure , I fast for 15 hours every day as an adjunct to a 10% carb diet. The certainty of results as reported by Cochrane are very low. The GRADE meta analysis shows only modest weight loss , more importantly it shows a drop in LDL-C, A1c and significant reductions in insulin levels. This is more important to me than weight loss .However, for me it is just one tool for keeping my weight where I want it as well as improving overall heath. I have never lost any weight with any other type of diet that didn't return within a month.
In the past, I always ate breakfast-even though I was not hungry- because I was told that skipping breakfast was an unhealthy habit. Since I learned about IF, I now defer eating in the morning until I am hungry; which is often not until 11 or 12. Voila! I am fasting! It's such an easy way for me to restrict calories.
Really interesting, thank you! I think the only diet that truly works is the one you can (mostly) stick to. And I’ve tried lots of them and like you, IF seems to work for me, but I don’t adhere to it too strictly. Thanks again!
Excellent post – thank you for breaking down the Cochrane review so clearly!
I turn to IF periodically, not for weight loss, but to help "reset" when I've started to eat too much junk. It's a psychological effect: Eating windows help me be more mindful about what I'm eating.
You mentioned that two book agents have turned down your idea that all diets are about the same for one's health. I wonder if you added (or would want to add) that each diet may have micro-benefits that depend on the individual. For instance, I imagine that IF would be no better or worse than any other diet if I were aiming for weight loss. But as for changing the content of what I eat, IF works better than anything else. I don't need a chart describing the Mediterranean diet. I need something that pushes me to think about what I eat next.
Your overall message certainly makes sense, no one diet works like magic for everyone. My quibble about the conclusion that fasting is about the same as any other calorie restriction Model is that the analysis lumps all the studies together and calls it intermittent fasting.
Fasting is just one of the methods I teach in my clinic, but I do suggest it frequently. But of course there are myriad models of IF and I strongly feel that each model needs to be evaluated separately. In my mind, for instance, the models that utilize calorie restriction to 500 calories on "fasting" days isn't fasting at all! That's just calorie restriction. Also, most studies of more traditional models focus on a 16 hour fasting window which, in my clinical experience, I rarely find works well. Jump up to a 20 hour window (with NO calorie restriction during the eating window) and success jumps up substantially. Of course clinical experience can not take the place of controlled trials, but lumping all of these "fasting" trials together even when they aren't actually having patients fast just muddies the water.
Thanks for a nice piece! I agree with the overall message, but I have my doubts as to whether there is actually much evidence to support this claim:
“If you’ve got what scientists call excess adiposity—too much fat—losing weight is a good idea for your health…”
It also must depend a whole lot on the *how*: Calorie restriction, weight loss meds or cutting off limbs? And how exactly do you measure and define the outcome, health?
I’m not just being pedantic: please guide me to relevant evidence or do a piece on this topic!
What I have heard from researchers in the UK is that the point of intermittent fasting has zero to do with calories. It's all about creating a healthy gut microbiome. Which in turn enhances our immune system and the gut/brain connection, etc. It's about letting the microbiome process all the food it needs to process, repair any of the gut lining that goes along with day to day wear, and then rest. Before we start to pummel it again with more food to process. It's about a healthy microbiome. Not about calorie restriction.
I have yet to see strong evidence - or even moderately convincing evidence - for any of the secondary proposed effects of intermittent fasting.
Moreover, these effects do not appear to show up in any meaningful way clinically in trials of the diet. If the diet does do something to the gut microbiome, it doesn't appear to impact any of the health metrics that we've so far tracked (which is all of the most important ones).
Correct me if I’m mistaken, but I believe your premise is, “most diets are about the same for your health.” However, your argument — and your conclusion — focus primarily on diets and losing weight.
I’ve always believed in the idea of calories in/calories out. I’m more interested in the effects of intermittent fasting versus other diets on health markers beyond those brought about by weight loss alone.
Very interesting thanks! Not sure if IF helps longevity and agree it’s no silver bullet for weight loss… but I’ve been dabbling with a 5-7hr eating window for a few years now and personally I find the increased metabolic flexibility is really neat! I can easily run 10-13mi in a 14-16hr fasted state which blows my mind.. I can go skiing for 4-5hrs on an empty stomach (no breakfast) without issue. It’s so cool not to stress about sugar on a run or snacks on the ski slope and not fear “bonking”. This has only been the case last few years while on IF. My last food for the day is usually 2-4p (unless for social reasons) and I never wake up (early bird) hungry. It’s been a fun experiment and I intend to keep it up.
Is there any evidence to support the long term (beyond a year or two) efficacy of *any* lifestyle modification plan for weight loss? My understanding that the only effective treatments (to date) for obesity are bariatric surgery and GLP-1 agonists.
Sort of what I expected and thanks for clarifying it. Do you think you will be doing something on the benefits of ice water immersion and its supposed health benefits? To me it is in the same boat as IF. I don't have anything against either but am dubious about the benefits.
Full disclosure , I fast for 15 hours every day as an adjunct to a 10% carb diet. The certainty of results as reported by Cochrane are very low. The GRADE meta analysis shows only modest weight loss , more importantly it shows a drop in LDL-C, A1c and significant reductions in insulin levels. This is more important to me than weight loss .However, for me it is just one tool for keeping my weight where I want it as well as improving overall heath. I have never lost any weight with any other type of diet that didn't return within a month.
In the past, I always ate breakfast-even though I was not hungry- because I was told that skipping breakfast was an unhealthy habit. Since I learned about IF, I now defer eating in the morning until I am hungry; which is often not until 11 or 12. Voila! I am fasting! It's such an easy way for me to restrict calories.
Really interesting, thank you! I think the only diet that truly works is the one you can (mostly) stick to. And I’ve tried lots of them and like you, IF seems to work for me, but I don’t adhere to it too strictly. Thanks again!