The nutritional science community is generally weak on data, because humans are expensive to study. This has led to prominent scientists cherry picking bad data and using correlation to back up shitty hypotheses. The Dr. Hall quoted in the article is a classic example of this. Attacking the study wherever he can, because it demonstrates how crappy his lifetime of low fat diet studies actually are.
It’s not clear to me how any of this is new.
What id like to hear is how researchers reconcile this concept with what is seen certain other countries, mostly Asian, where rice is a staple of their diet, and where you don’t see the levels of obesity we have in the US.
It seems that the carbohydrate intake in these study is mostly based on processed carbohydrates, which are distinguished from unprocessed/lesser processed ones (like beans, fruits, and to a lesser extent rice). Those make a huge difference for our metabolism compared to white flour or industrial sugar. Fruits may contain a lot of sugar as well but it seems to make a big difference if sugar comes with fibres or not.
In my country (France) bread used to be a staple of the diet and there was no obesity epidemic at the time.
Perhaps it has to do with total food intake. I live in Bangkok at the moment, rice is a staple food and Thais eat all the time (they remind me of Hobbits). Portions are small though, so perhaps that's why I don't see a lot of overweight people.
This is correct from my perspective as well (I live in Japan). Not just portion sizes, but total calories in a meal are dramatically smaller. I went back to the UK a week ago for a visit and I was stunned to see menus with calories listed that had individual meals (without drinks or desert!) listed as considerably over 1000 kcal.
Japanese people often have a good breakfast, but then eat maybe 5-700 kcal for lunch (in the form of a bentou) and maybe the same for dinner. Sometimes you get a set bentou at work and it often works out to about 1000 kcal -- but nobody I know who eats those ever eats dinner. They'll have a drink or two after work with whatever otoshi (side dish imposed on you as a cover charge in the drinking establishment) and maybe some snacks.
It's about portions when eating Asian food in Singapore my rice always used to finish before the proteins that come with a dish so I sometimes ordered extra rice. Plus Asian food have lots of soups on the sides so I think their carbohydrate and protein intake is more balanced then it looks.
Sugars in general, and high-fructose corn syrup in particular. It is added to a lot of products in the US "to make them more pallatable". Which is an euphemism for "to sell more".
Rice is carbs, yes. But it also fills the stomach (for a while, at least - beans are better and proteins are much better on that field). Sugar/Syrup has the opposite effect. It is addictive and it makes you crave for more. It is also very cheap. So food vendors add it to everything - to sell you more. Meat. Cheese. To me (from Europe) US bread tastes like cake.
European and Asian food producers are gradually catching up on this strategy and are adding extra sugars, so the obesity levels are also increasing, especially in big cities:
To me doesn't make sense that something so unhealthy as corn syrup (and other sugars) isn't more heavily taxed. Right now food producers are making their buck by passing the bill to the US health care, which is a big chunk of the US central budget (and also very inefficient). It's a drag on the whole US economy, in addition of causing a lot of human tragedy.
I think we do a disservice to people to lump all carbs together. For many, it makes any dietary change seem overwhelming. I doubt many people are getting fat eating a diet of fish, veggies, and rice. In fact, that sounds like a healthy meal.
The problem is that people are eating candy bars, sugared soda, potato chips, french fries, pop tarts, and basically crap.
> It found that overweight adults who cut carbohydrates from their diets and replaced them with fat sharply increased their metabolisms. After five months on the diet, their bodies burned roughly 250 calories more per day than people who ate a high-carb, low-fat diet
Is it healthy in the long term to increase metabolism like this? Animal studies strongly suggest that calorie restriction is beneficial to longevity, and there is anecdotal evidence in humans (e.g. Okinawans). A higher resting metabolism means more aerobic respiration, which generates reactive oxygen species, which damages cells. Better to go the hard way and simply eat less.
From a much broader, evolutionary or theory-of-life perspective.. eating less would a be a step backwards, towards eating nothing - not existing, or pure entropic. Every advance in the development of life is a fight against entropic death- as organisms move farther and farther from this, there will be increasing forces of nature fighting in the opposite direction - that is a sign you are moving in the RIGHT direction.
Good point. I was struggling with the idea that lower metabolism might mean higher efficiency (like when we started cooking food). And being Paleo/carb restricting could be seen as a step back too!
Maybe we should continue eating processed, insulin spiking, gut destroying foods and see how our body adapts next? (That's not sarcastic, just a proposal) How is our body adapting currently? (Diabetes is not an adaptation)
Being sedentary leads to a host of maladies, while constantly doing bootcamps, overtraining, pro sports or cross-continental marathons causes enormous oxidative stress, tissue damage and more risks of premature wear, cancer and aging... so there's a happy medium for a healthy, good quality of and longer life.
Also, between catabolic processes that destroy the body to keep it going and binge eating, there's a happy amount of fasting and cutting calories to a sustainable amount... lipogenesis, ULDLs, and VLDLs generally aren't good.
I'm not an expert in this, but the historical Okinawa diet doesn't have as much in simple carbohydrates compared to other lifestyles[1]. I think calorie intake is a notable aspect like you mentioned, but eating foods with a higher satiety strikes me as making a larger impact as well.
It depends on the medical problems the individual is facing.
Overweight people have the problem of a low metabolism due to diets. Which is why diets stop working.
So in them, no, a low metabolism isn’t OK, especially because that low metabolism isn’t correlated with hunger signals.
Speaking of animal studies there’s also this idea that in nature everything is cyclical. You’ve got periods of feasting and you’ve got periods of famine. Eating less all the time is probably not good for longevity.
Diets don't cause low metabolism, except in the sense that when you lose weight it takes fewer calories to keep the remaining smaller amount of tissue alive. So as you lose weight, in order to continue losing weight at the same rate you have to keep cutting calories even further.
That the "basal metabolic rate" slows down when dieting is shown by many studies on diet. The weight loss isn't linear and slows down over time, in about 6 months or so, even if the caloric deficit is sustained. Not only that, but the basal metabolic rate stays low even after people start eating normally again.
That group on average burned 2607 before the competition, but only about 2000 calories after the competition, even if they continued to do plenty of exercise afterwards. They also regained much of that lost weight.
Thin people shouldn't be giving dieting advice, because the obvious confounder is having a well functioning metabolism, whereas overweight people don't ;-) This is made worse by doctors doing it for the same reasons as everybody else. Until they get fat themselves, realizing only afterwards that gluttony wasn't the problem after all.
The concept of a damaged metabolism doesn't make sense. Your body doesn't waste energy for the hell of it, there is not even a dial for the metabolism to change. Your organs just perform their functions using energy in the process. An organ can't reduce its energy expenditure without compromising its function. Not to mention that if it were possible to live with less calories, evolution would have eked out that benefit millions of years ago.
It is well known that the resting energy expenditure is a simple function of body composition, with no influence of age, gender or body weight [0]
The first study attributes the drop in energy expenditure to the non-resting energy expenditure, which isn't part of the metabolism. There is no saying that difference in energy expenditure isn't compensated for in real life situations, the study freely admits the difficulty in controlling for it.
The second study shows a drop of energy expenditure of a whopping 2%. Another explanation of the effect could just be that the formula they use to predict the resting metabolic rate is too simple, it literally only uses two variables: fat mass and fat free mass. You wouldn't expect such a simple formula to hold over a wide range of weights, it's surprising that it works so well, to within 2%, in the first place.
The third one, the Biggest Loser study, is the only one of the three that is just plain wrong. I'm very surprised to see it appear on Scientific American. In the study, they invent their own formula for the RMR by doing a multilinear regression in 4 variables on 14 subjects. This formula is different from the usual formulae and tellingly underestimates the caloric need of fat tissue (1.5 kcal/d/kg instead of 3.5 kcal/d/kg or 5.7 kcal/d/kg as in your second study). Then they apply that formula, which was calibrated only on the obese subjects, on the people after they lost weight and compare that to the measured RMR, instead of using a more standard formula, and interpret the difference as metabolic damage. No wonder it doesn't work. If you instead plug in the data in a more accepted formula, you see little difference with the measured metabolic rate. Heck, even I have massive metabolic damage according to that formula, their formula estimates my RMR at a whopping 2460 kcal/d, which isn't my total daily energy expenditure. The measured RMR in the article, 1903 kcal/d, wouldn't be unusual for people of that weight.
That study should have never gotten past peer review, and I don't know why it hasn't been retracted yet.
I don't understand the focus on metabolism anyway. Even if a damaged metabolism existed (it doesn't), that still wouldn't change anything if you ate less. The problem lies in a miscalibration between satiation and energy need, we should be figuring out why some people are more hungry than others, and what we can do to change that.
There's also the concept of baseline and highly adaptability to continued circumstances, so presumably metabolism is highly elastic if gradually tuned over the years.
Some of the best things in life involved expending a lot of calories. Even if calorie restriction "works" in the sense of slightly extending human lifespan (and there's no real evidence for that yet) it's hard to see that as a net improvement.
I've seen videos of people who are actually trying long term calorie restriction to live longer and they look terrible.
simplified: this, again, is a misconception - fat doesn't per se clog the arteries. LDL (bad) to HDL (good) cholesterol levels do that, which are influenced by a lot of factors, like smoking, alcohol, certain kinds of fats and simple carbs (sugar).
Wow, another study that fails to actually include a low carb diet:
>"During the test phase, high, moderate, and low carbohydrate diets varied in carbohydrate (60%, 40%, and 20% of total energy, respectively)"
A low carb diet is going to be 100g (~ 400 cal or 20% caloric intake) per day at the absolute maximum. Really it should be half to a quarter of that and you will not feel the need to restrict your eating at all. The way it works for getting to a normal weight is that you feel less hungry if you limit your carb intake to those levels.
It's amazing how awful this academic nutrition research is, they just make up their own false definitions about things then draw conclusions about what people care about.
Keto diet is ideally no more than 20-30g of carbs per day, with the majority of your calories coming from fat macros. This study would explain why keto enables shedding body fat so quickly (which is usually waived away, by myself included, as satiation from fats and protein vs carbs).
>"Keto diet is ideally no more than 20-30g of carbs per day, with the majority of your macros coming from fats. This study would explain why keto enables shedding body fat so quickly"
How so? Even their lowest carb diet was much higher than 20-30g per day.
I assume (perhaps incorrectly), that if their lowest carb diet tested is still much higher and they're seeing metabolism increases at that carbohydrate intake level, the effect would be more pronounced at even lower (ie keto) carbohydrate intake levels. Speaking only for myself, when I've utilized the ketogenic diet to lose weight, I can lose upwards of 3lbs a week doing nothing (maintaining a sedentary lifestyle) except restricting carbohydrate intake below 20g/day (eating my fill of eggs, bacon, hamburger, and cheese).
This completely ignores any gut microbiome changes (and corresponding nutrient absorption changes that might occur) due to a change in diet.
Yes, you simply consume less calories on a keto diet because you feel less hungry. For whatever reason consuming carbs over a certain threshold is addictive.
Either way, they did not include a keto diet. Instead they used a "relatively low carb" diet of 20% carbs. Since ketosis is an entirely different metabolic state there is no reason to extrapolate from 50%-5% (keto). They have no theory so they need to actually measure this, and every single academic nutrition study I've ever seen on % carbohydrates in the diet fails to do it.
You cannot get "macros" from fat - you get energy, but you need more than energy to survive. If you don't get carbs, your body breaks muscle tissue to produce it. There's also evidence that muscle is burned first before fat deposits. The only thing that fasting does and people misunderstand the results is increasing HGH, but any growth factors are cancer factors,m too. Increased metabolism also means faster aging.
I corrected that part of my comment ("with the majority of your calories coming from fat macros"). Regarding "If you don't get carbs, your body breaks muscle tissue to produce it", this is a myth (as long as you are consuming an adequate amount of protein; strength training is helpful if able) [1]. Your body will produce ketone/ketone bodies (an adequate substitute for bodily organs demanding glucose) once your glucose stores are exhausted, and will continue to do so as long as you restrict ingestion of carbohydrates and don't run out of body fat.
> More recently, Willi et al. examined the efficacy and metabolic impact of a VLCARB in the treatment of morbidly obese adolescents [4]. Six adolescents weighing an average of 147.8 kg consumed the VLCARB (25 g of carbohydrate/day) for 8 weeks. The results indicated that the weight loss with VLCARB is rapid, consistent, and almost exclusively from body fat stores. Changes in lean body mass, as estimated from DEXA and urinary creatinine, were not significant over the term of treatment. Bioelectrical impedance measurements reflected a greater loss of lean body mass, but changes in total body fluid and electrolyte content, as a result of dietary ketosis, may complicate these measurements.
> Although more long-term studies are needed before a firm conclusion can be drawn, it appears, from most literature studied, that a VLCARB is, if anything, protective against muscle protein catabolism during energy restriction, provided that it contains adequate amounts of protein.
You can't eat protein on a fast. Protein also increases blood sugar, and too much of it is detrimental in many ways and growth factors such as IGF-1 being just one.
You're moving the goal posts. We're not talking about a fast, we're talking about a very low carbohydrate diet. The paper I reference demonstrates that a carbohydrate restriction does not incur muscular catabolism when protein is a component of your low carbohydrate diet (which should primarily be fats to prevent excessive protein from kicking you out of ketosis).
Not really as low-carb diets are done mostly by people who do IF. Not all carbs are not evil! We've evolved to digest milk in adulthood and take advantage of slow carbs. The bad carbs are the refined ones - we haven't had much of these in the past. Low-carb diets are especially unsuited for women. If you look at people who lived healthy and long lives, they weren't gulping on coconut oil and refined MCT oils. Anyway, I don't think empty sugar calories are much different than empty fat calories. Carbs bring more nutrients than fats like coconut, for example. Nobody also cares on the microbiota effect of fat overload! Again, if you have epilepsy or schizophrenia, okay, no doubt, keto is great as therapy, but is it great for just anybody and does it lead to a long healthy life? There are no data to support such a statement!
On the contrary, all anecdotal data points that moderation is the best strategy. Oh, wait - 6 meals a day is also a modern brainfart - people used to eat 1-2 times a day with no snacking! So, enough fad diets with no scientific proof behind them! The only thing that makes sense today is backed by research - maintain mitochondrial QC, cycle mito fusion with fission - all chronic diseases pretty much are caused by dysfunctional mitochondria, and I don't think keto supports that strategy well!
> as low-carb diets are done mostly by people who do IF
What? Maybe, but I think citation is needed there. The most widely popular keto diet, Atkins, doesn't say a thing about fasting - when you boil it down, and don't do any of the stupid carb-replacement recipe trickery that a lot of people do, Atkins equates to: take your normal meal with meat, starch, and vegetable, and stop making the starch, eat a little more vegetable if you want. Voila, there goes 500-1000 calories a day, more if you're eating starchy/sugary snacks. And you won't be hungry between meals. It's not rocket science.
Yes, the more frequently you eat, the faster your metabolism gets, and you get hungry faster. I'm not sure why people came up with the nonsense that faster metabolism is better as since when accelerating aging is desired? Well, muscle mass also ups basal metabolic rate, but that's a bit different mechanism.
You missed the part where the body uses Glycogen resources while on a high carb diet and stores excess carbs as fat. You only lose fat if your blood glucose levels are low enough. And obese people often are pre-diabetic and actually have to eat low carb and fast to get their levels low enough to actually burn fat.
Not at all. Don't eat excessively, and caloric restriction is the way to go and proven over the ages - Okinawans have a rule of how much to eat - read about it!
Diabetic people actually need carbs as if they use insulin shots, they often get hypoglycemic. If you have an active lifestyle, your BG actually just replenishes your glycogen depots and possibly you don't have much excess fat anyway. So, live a healthy lifestyle and then a moderate diet will work just perfectly!
Anyway, fat deposits in moderate size are not a bad thing. In fact, in many cases, they save lives - the evolution did not invent them without a solid reason. Yes, excessive fat is bad for men as it's feminizing, but doesn't have a huge impact on women when you look at the studies. There's also a good reason why fat is not so easily mobilized.
Yes, a low carb diet makes people feel less hungry, so they eat less. A (supposedly) "normal" carb diet makes many people hungrier than they should be so they eat excessively.
That's not true. Fast carbs make you hungry again. Slow carbs satiate pretty well. Eating frequently also makes you hungry faster. Two meals a day with slow carbs won't make you eat more.
Well, all you need to do is try it to see for yourself. It takes a week, just eat meat and cobb/greek salad and broiled broccoli and green beans or whatever. Basically just cut out the grains (+ potatoes/fries, etc) they try to trick you into eating. That is all it takes.
I've done it, actually, and do it frequently - as an Orthodox Christian, our Nativity Fast just started and we eat beans and lentils, and I lose weight after each fast, and I never feel hungry. Don't fall for the marketing stuff! Eat traditional foods, and you will feel great! I stopped feeling hunger after I eliminated the refined carbs breakfast from my routine, and practice 16-hour IF daily. Initially, I was into the ketotard camp, but my liver paid for the fat overload, and I did not lose stubborn fat - and how could I when I was ingesting copious amounts of it not allowing the mobilization of my own! I started to lose weight with the Orthodox fasts when you have long periods of no dairy, meat, or fish. The cycling between vegan and omnivore diets has been great, and no wonder millions have been practicing it for hundreds and thousands of years! I laugh when I see people wasting so much money on exogenous ketones or fancy fats, which nobody in human history has been eating in such amounts! This is no different than raw kale juice. People make the mistake of not understanding hormesis and that each nutrient (micro or macro) has a range of positive influence on health and any intake outside of that range is detrimental. And that this range is never open on either end! Even small amounts of radiations are beneficial and at the same time - huge amounts of plain water are toxic. The tricky part is that the rage is specific to each person, it depends on the genotype, epigenetic, and many other factors such as climate, location, time in the day and year, and so on. All these diets ignore the most recent scientific discovery - epigenetics! We should eat what we're best adapted to and I'm sure my ancestors did not eat coconut oil, nor limited slow carbs like beans and legumes. On the contrary, they've had a balanced diet, did not avoid fatty meats, but didn't overeat fat either. For sure they didn't have the habit of snacking and didn't eat breakfast, and for sure ate within 6 or 8 hours. And, last, but not least - they didn't sleep as little as I or you do. Sleep length and quality are finally getting attention in the whole puzzle of health! Chronobiology is now getting more and more attention and it goes back to what I said earlier - we should stick to what we're adapted best to... unless we want to sacrifice our lives to influence (not necessarily positively!) the lives of our successors!
> "I've done it, actually, and do it frequently - as an Orthodox Christian, our Nativity Fast just started and we eat beans and lentils, and I lose weight after each fast, and I never feel hungry."
I doubt you really feel that comfortable because then why wouldnt you eat like this all the time? Just that you are referring to it as a "fast" tells me you are craving food. If you ate less because you felt satiated, you wouldnt refer to it as a fast.
I don't even know what you are talking about regarding overeating fat. My experience is just cut out the grains and sugars and eat whatever else you want. If you crave fat, then you eat it. There is no overeating involved. That is the entire point, if you keep your carbs low enough you do not want to overeat anything. There is no self-control involved, in fact you need to sometimes force yourself to feel like eating for social/etc reasons.
There is also no need to purchase "fancy fats", you do probably have to prepare your own food though since sugar is added to everything prepared for you.
>"All these diets ignore the most recent scientific discovery - epigenetics!"
This is hardly recent, and while I'm sure it has some sort of relationship to a persons optimal diet, no one has any idea what that is.
You have no idea what you're talking about, honestly. Our family does not use sugar at all. And, no, I don't feel hunger and 90% of what you mean by "hunger" is habitual, not real hunger caused by ghrelin. When we fast, and it's unfortunate that English has such a misrepresenting word, we don't get tempted by meat and dairy. I am not supporting vegetarianism and veganism, on the contrary, but I don't think the meat overeating habits are healthy and the data shows it. For example, upping your growth factors, overloading yourself with iron, eating charred meat is proven to be detrimental to health. Now everybody's lining up to buy bone broth not knowing that bones often accumulate heavy metals like lead and America is polluted with lead, but that's not just all. Anyway, my point was that people should eat quality foods aligned with their genetic and epigenetic profile, use the least possible processing and stick to traditional cooking methods. Don't eat too much carbs, don't eat too much fats, don't eat too much meat - this is the optimal strategy at this point as I've been following diets for nearly 20 years and there's no perfect on except the balanced real-foods one!
>"upping your growth factors, overloading yourself with iron, eating charred meat is proven to be detrimental to health."
All I did is stop eating bread and preparing my own food so there was no sugar in it. So this extreme diet you are talking about seems like a strawman to me.
>"people should eat quality foods aligned with their genetic and epigenetic profile"
No one knows what this would be.
> "Don't eat too much carbs, don't eat too much fats, don't eat too much meat"
Which your body lets you know via a satiated feeling without gaining undesirable weight. "Too much carbs" seems to be over 50-100 g/day for most people. If it wasn't, they wouldn't eat more than was healthy.
Fat provides energy. Vitamins and minerals are either fat or water soluble. Meat will provide copious protein and all of the amino acids of which they are made, essential ones and those humans can synthesise themselves. An all meat diet is perfectly healthy as long as you have enough energy, vitamins and minerals, all of which can be tackled by eating adequate fat.
You don't need huge amounts of fat to absorb vitamins. For example, all vitamin D3 pills have a drop of olive oil. Ketotards eat a huge amount of fat thinking they are providing nutrients. Yes, you need fats, just like you need carbs, but not in excess. Meat has vitamins and minerals, too. I'm not against meat, I'm against overeating when you're 30+.
An all meat diet is perfectly healthy if it includes enough fat. You started off by saying that you can’t get anything but energy from fat and that you need more than energy to survive.
> You cannot get "macros" from fat - you get energy, but you need more than energy to survive.
That’s not true. If you eat fat as part of an all meat diet you’ll have enough energy and nutrition to survive without problems. I wouldn’t be too surprised if a diet that was mostly fat with some lean meat worked as well.
> If you don't get carbs, your body breaks muscle tissue to produce it. There's also evidence that muscle is burned first before fat deposits.
Neither of these are true either. If you’re fasting and you stop exercising you will lose muscle rapidly as it gets broken down but if you continue exercising you’ll lose fat and a very small amount of muscle, accelerating over time.
> Ketotards eat a huge amount of fat thinking they are providing nutrients. Yes, you need fats, just like you need carbs, but not in excess.
If you’re eating nothing but meat you do in fact need fat to get enough nutrients. Given that carbohydrates are unnecessary to a healthy diet and meat is also unnecessary any notion of excess that claims to be acultural is ridiculous.
> Meat has vitamins and minerals, too. I'm not against meat, I'm against overeating when you're 30+.
This is the first time you’ve mentioned age or overeating. Every statement of fact you’ve made has been wrong. What was the point of taking part in this discussion?
No statement I've made is wrong. Obviously, growth factors are necessary when you're young and pro-cancer when you're old and have higher cancer risks. I'm just clarifying as obviously, the obvious facts are not clear to this audience!
Anyway, I keep saying - surviving and thriving are two different things. I want to thrive, not just to survive. I get tired of people giving the Inuit as an example. Yes, they survive on predominantly fatty meat (although they eat starchy roots, too, okay, "ate" as they've modernized), but I don't want to be anything like them, sorry, no offense! There are many tribes who are healthier, look better, and eat plenty of starches! Here's a recent article [1] about a tribe, which loads on starches, and looks and functions better than the Inuit. :D
Food is information. Eating high-fat may give some immediate results, but we have no idea what's the effect in long-term - nobody has such diet, sorry!
Also, cite a study claiming that carbs are not necessary for health? You're making a mistake again and again - just like fats carry other nutrients such as vitamin K, D, etc., carbs also come in concert with many others. It's 2018 and it's clear to all camps that refined foods are empty. I'm not asking you to eat refined tapioca starch, I'm telling you that you should eat sweet potatoes, yams, beans, legumes, etc. Of course, there's no perfect food and many plants have natural anti-nutrients just like meat and dairy do, but, again, we've evolved to handle lectins and others decently not to mention that many cooking practices also evolved unknowingly to reduce the toxicity.
I am surprised that nobody here argues an obvious detriment of carbs - their role in the formation of endogenous AGEs (advanced glycation endproducts), but, of course, for their formation, you need protein, too. At the same time, animal products are rich in exogenous AGEs [2].
Not true. If it was the Eskimos, Inuit and other people who lived in the Arctic circle before modernity encroached there would have been unable to survive. If you’re eating all lean meat you’ll have some kind of deficiency disease inside a month. If you eat fatty meat as well you’ll almost certainly get everything you need and if you eat organ meat as well as muscle and fat we know you can eat that for a year with no ill effects whatsoever.
Given an average human consumption of 2250 calories per day, they're telling us that we could feed ~10% fewer people if we moved to a fat-based diet globally?
Depends where the fats come from. It takes a lot more resources to grow 100 calories of animal than 100 calories of plant. I imagine there is still a significant difference of resources needed to produce 100 calories of plant-based fat and 100 calories of animal-based fat.
You would think so, but thermodynamics do not apply to these scientists. People on an isocaloric high fat diet will expend 10 % more calories without loosing weight (their claim). I'm smelling the beginning of a perpetual motion machine.
In case anyone is interested, this thread includes a more specific set of methodological critiques made by Dr. Kevin Hall at this week's ObesityWeek conference (unfortunately does not include Dr. Ludwig's rebuttal):
https://twitter.com/YoniFreedhoff/status/1062760576869371910
Hall's research focus is on mathematical metabolism models, so his critique comes from that angle: it is possible doubly-labeled water measurements of energy expenditure may behave differently in a lower-carb environment, so the observed EE difference may not be meaningful. Ludwig actually briefly addresses this in their published paper, citing a few other studies suggesting that DLW is accurate and carb intake does not mess with isotopic measurements.
Hard to tell if this is a meaningful advance for the low-carb crowd, or just an artifact of insufficiently validated methodology.
I am interested in what the article did not say, as it may shed some light on this critique. Specifically, the weight differences between the groups at the end of the second phase of the study.
The second phase of the study involved breaking the participants into three groups. They were fed the same number of calories. Each group had several biomarkers tracked. This included daily calories burned and ghrelin (a hormone) levels. I understand the critique targets the measurement of calories burned, via the doubly labeled water measurement of the metabolic date.
What I wonder is what the average weight change was for each of the three groups after 5 months. If the claim is that the high-fat diet group burned an average of 250 calories more, then that should be reflected in an additional weight loss of about 10 pounds (250 calories per day * 5 months * 30 days in a month / 3700 calories in 1 pound of fat). This would be because all the people across all groups were fed the same number of calories. If one group used 250 calories more per day, these extra calories had to come from somewhere. They would have to come from fat stores and muscle tissue inside of the body, resulting in a weight loss.
If the weight loss for that group correlates with the doubly labeled water measurement then it gives more credence to the study's results. If it does not correlate with weight loss, it is suspicious to claim that one group of people burned 250 more calories than the other over 5 months while eating the same number of calories but did not lose any weight.
Yup - this line of reasoning is also expressed by Dr. Hall, in the slide here [1]. To answer your question, the study specifically states: "On average, body weight changed by less than 1 kg during the test phase, with no significant difference by diet group in either the intention-to-treat (P=0.43) or per protocol (P=0.19) analysis."
It is interesting that the study authors highlight the higher energy expenditure as an advantage for weight loss, but do not seem to directly address that they did not observe this advantage during the 20 week study period.
Already commented elsewhere, but the researchers noted that the fed the participants different amounts of food each day as necessary to maintain weight. They were testing metabolic differences associated with the ratio of carbohydrates in the diet.
Studies have already shown that weight loss affects metabolic rates.
Thanks for clarifying - this is an important point and seems to explain why there was no noticeable weight loss.
From the paper: "During the test phase, participants’ energy intake was adjusted periodically to maintain weight loss within 2 kg of the level achieved before randomization."
The purpose of the study was to test metabolism, not weight loss. The tested variable was the amount of calories/day attributable to carbohydrates.
A key part of the study was that they fed the participants more or less each day to maintain weight.
In other words, there should not have been any weight change at all, as weight change would have confounded the results since weight loss is known to effect metabolism.
If that is the case, then it makes sense that they did not lose weight.
However, from a layman perspective, it seems like it would be nice to be able to collaborate the measure of increased metabolism not only through one method (doubly labeled water) but also through weight loss over time.
It's like having an inaccurate measuring stick and basing the results of a study solely on measurements made by that one stick, while at the same time making an effort to make sure that no other means of measuring exist.
What this article says is true and has been known for quite some time. (Not exactly sure why it's so revalatory in the article)
I've also tried it for years as well to lose and keep weight down. But it's actually not healthy for you. You're better off eating a balanced diet, not too much of it, and exercising.
Yes, an engine burning through more fuel will deteriorate faster. Carbs are easy fuel that won't wear out the system as much as having to process fats and protein for that same energy benefit.
>> The trial cost $12 million and was supported largely by a grant from the Nutrition Science Initiative, a nonprofit research group co-founded by Gary Taubes, a science and health journalist and proponent of low-carbohydrate diets.
So, a non-profit funded by a gentleman who advocates for low-carbohydrate diets found that low-carbohydrate diets are good for you.
That's the beauty of science: it doesn't matter what it looks like. It only matters what it is. I'd learn how to critically read a scientific study paper, if you don't know how already. You're just begging to be lied to if you don't.
No shit. This has been common knowledge for a long time, except among people who go to major media outlets for health advice, rather than factual scientific literature...
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[ 3.1 ms ] story [ 173 ms ] threadThe nutritional science community is generally weak on data, because humans are expensive to study. This has led to prominent scientists cherry picking bad data and using correlation to back up shitty hypotheses. The Dr. Hall quoted in the article is a classic example of this. Attacking the study wherever he can, because it demonstrates how crappy his lifetime of low fat diet studies actually are.
Perhaps it has to do with total food intake. I live in Bangkok at the moment, rice is a staple food and Thais eat all the time (they remind me of Hobbits). Portions are small though, so perhaps that's why I don't see a lot of overweight people.
Japanese people often have a good breakfast, but then eat maybe 5-700 kcal for lunch (in the form of a bentou) and maybe the same for dinner. Sometimes you get a set bentou at work and it often works out to about 1000 kcal -- but nobody I know who eats those ever eats dinner. They'll have a drink or two after work with whatever otoshi (side dish imposed on you as a cover charge in the drinking establishment) and maybe some snacks.
I feel the problem of the US is a cultural one which goes beyond the basic carb/fat split.
Healthy Asian populations also eat a lot of fish and seaweed. They eat much more salt (!) than we do. And they don’t eat so much junk food.
https://www.reddit.com/r/nutrition/comments/9x47lg/are_simpl...
Rice is carbs, yes. But it also fills the stomach (for a while, at least - beans are better and proteins are much better on that field). Sugar/Syrup has the opposite effect. It is addictive and it makes you crave for more. It is also very cheap. So food vendors add it to everything - to sell you more. Meat. Cheese. To me (from Europe) US bread tastes like cake.
European and Asian food producers are gradually catching up on this strategy and are adding extra sugars, so the obesity levels are also increasing, especially in big cities:
https://en.wikipedia.org/wiki/Obesity_in_China
It just has not reached US levels.
To me doesn't make sense that something so unhealthy as corn syrup (and other sugars) isn't more heavily taxed. Right now food producers are making their buck by passing the bill to the US health care, which is a big chunk of the US central budget (and also very inefficient). It's a drag on the whole US economy, in addition of causing a lot of human tragedy.
The problem is that people are eating candy bars, sugared soda, potato chips, french fries, pop tarts, and basically crap.
Is it healthy in the long term to increase metabolism like this? Animal studies strongly suggest that calorie restriction is beneficial to longevity, and there is anecdotal evidence in humans (e.g. Okinawans). A higher resting metabolism means more aerobic respiration, which generates reactive oxygen species, which damages cells. Better to go the hard way and simply eat less.
But still a very interesting point you make.
Maybe we should continue eating processed, insulin spiking, gut destroying foods and see how our body adapts next? (That's not sarcastic, just a proposal) How is our body adapting currently? (Diabetes is not an adaptation)
Also, between catabolic processes that destroy the body to keep it going and binge eating, there's a happy amount of fasting and cutting calories to a sustainable amount... lipogenesis, ULDLs, and VLDLs generally aren't good.
https://en.wikipedia.org/wiki/Okinawa_diet
Overweight people have the problem of a low metabolism due to diets. Which is why diets stop working. So in them, no, a low metabolism isn’t OK, especially because that low metabolism isn’t correlated with hunger signals.
Speaking of animal studies there’s also this idea that in nature everything is cyclical. You’ve got periods of feasting and you’ve got periods of famine. Eating less all the time is probably not good for longevity.
That is, this study seems to claim that what you eat can impact your metabolism.
https://www.scientificamerican.com/article/6-years-after-the...
Here's a study: https://www.ncbi.nlm.nih.gov/pubmed/18842775
Here's another one: https://www.ncbi.nlm.nih.gov/pubmed/23535105
Another interesting finding is what happened with the Biggest Loser contestants: https://www.scientificamerican.com/article/6-years-after-the...
That group on average burned 2607 before the competition, but only about 2000 calories after the competition, even if they continued to do plenty of exercise afterwards. They also regained much of that lost weight.
Thin people shouldn't be giving dieting advice, because the obvious confounder is having a well functioning metabolism, whereas overweight people don't ;-) This is made worse by doctors doing it for the same reasons as everybody else. Until they get fat themselves, realizing only afterwards that gluttony wasn't the problem after all.
It is well known that the resting energy expenditure is a simple function of body composition, with no influence of age, gender or body weight [0]
The first study attributes the drop in energy expenditure to the non-resting energy expenditure, which isn't part of the metabolism. There is no saying that difference in energy expenditure isn't compensated for in real life situations, the study freely admits the difficulty in controlling for it.
The second study shows a drop of energy expenditure of a whopping 2%. Another explanation of the effect could just be that the formula they use to predict the resting metabolic rate is too simple, it literally only uses two variables: fat mass and fat free mass. You wouldn't expect such a simple formula to hold over a wide range of weights, it's surprising that it works so well, to within 2%, in the first place.
The third one, the Biggest Loser study, is the only one of the three that is just plain wrong. I'm very surprised to see it appear on Scientific American. In the study, they invent their own formula for the RMR by doing a multilinear regression in 4 variables on 14 subjects. This formula is different from the usual formulae and tellingly underestimates the caloric need of fat tissue (1.5 kcal/d/kg instead of 3.5 kcal/d/kg or 5.7 kcal/d/kg as in your second study). Then they apply that formula, which was calibrated only on the obese subjects, on the people after they lost weight and compare that to the measured RMR, instead of using a more standard formula, and interpret the difference as metabolic damage. No wonder it doesn't work. If you instead plug in the data in a more accepted formula, you see little difference with the measured metabolic rate. Heck, even I have massive metabolic damage according to that formula, their formula estimates my RMR at a whopping 2460 kcal/d, which isn't my total daily energy expenditure. The measured RMR in the article, 1903 kcal/d, wouldn't be unusual for people of that weight.
That study should have never gotten past peer review, and I don't know why it hasn't been retracted yet.
I don't understand the focus on metabolism anyway. Even if a damaged metabolism existed (it doesn't), that still wouldn't change anything if you ate less. The problem lies in a miscalibration between satiation and energy need, we should be figuring out why some people are more hungry than others, and what we can do to change that.
0: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3139779/
you don't think eg amenorrhea features?
I've seen videos of people who are actually trying long term calorie restriction to live longer and they look terrible.
It lead to very unhealthy habits.
As anecdotal evidence that's the Inuit diet.
>"During the test phase, high, moderate, and low carbohydrate diets varied in carbohydrate (60%, 40%, and 20% of total energy, respectively)"
A low carb diet is going to be 100g (~ 400 cal or 20% caloric intake) per day at the absolute maximum. Really it should be half to a quarter of that and you will not feel the need to restrict your eating at all. The way it works for getting to a normal weight is that you feel less hungry if you limit your carb intake to those levels.
It's amazing how awful this academic nutrition research is, they just make up their own false definitions about things then draw conclusions about what people care about.
How so? Even their lowest carb diet was much higher than 20-30g per day.
This completely ignores any gut microbiome changes (and corresponding nutrient absorption changes that might occur) due to a change in diet.
Either way, they did not include a keto diet. Instead they used a "relatively low carb" diet of 20% carbs. Since ketosis is an entirely different metabolic state there is no reason to extrapolate from 50%-5% (keto). They have no theory so they need to actually measure this, and every single academic nutrition study I've ever seen on % carbohydrates in the diet fails to do it.
[1] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1373635/
> More recently, Willi et al. examined the efficacy and metabolic impact of a VLCARB in the treatment of morbidly obese adolescents [4]. Six adolescents weighing an average of 147.8 kg consumed the VLCARB (25 g of carbohydrate/day) for 8 weeks. The results indicated that the weight loss with VLCARB is rapid, consistent, and almost exclusively from body fat stores. Changes in lean body mass, as estimated from DEXA and urinary creatinine, were not significant over the term of treatment. Bioelectrical impedance measurements reflected a greater loss of lean body mass, but changes in total body fluid and electrolyte content, as a result of dietary ketosis, may complicate these measurements.
> Although more long-term studies are needed before a firm conclusion can be drawn, it appears, from most literature studied, that a VLCARB is, if anything, protective against muscle protein catabolism during energy restriction, provided that it contains adequate amounts of protein.
What? Maybe, but I think citation is needed there. The most widely popular keto diet, Atkins, doesn't say a thing about fasting - when you boil it down, and don't do any of the stupid carb-replacement recipe trickery that a lot of people do, Atkins equates to: take your normal meal with meat, starch, and vegetable, and stop making the starch, eat a little more vegetable if you want. Voila, there goes 500-1000 calories a day, more if you're eating starchy/sugary snacks. And you won't be hungry between meals. It's not rocket science.
Diabetic people actually need carbs as if they use insulin shots, they often get hypoglycemic. If you have an active lifestyle, your BG actually just replenishes your glycogen depots and possibly you don't have much excess fat anyway. So, live a healthy lifestyle and then a moderate diet will work just perfectly!
Anyway, fat deposits in moderate size are not a bad thing. In fact, in many cases, they save lives - the evolution did not invent them without a solid reason. Yes, excessive fat is bad for men as it's feminizing, but doesn't have a huge impact on women when you look at the studies. There's also a good reason why fat is not so easily mobilized.
Yes, a low carb diet makes people feel less hungry, so they eat less. A (supposedly) "normal" carb diet makes many people hungrier than they should be so they eat excessively.
I doubt you really feel that comfortable because then why wouldnt you eat like this all the time? Just that you are referring to it as a "fast" tells me you are craving food. If you ate less because you felt satiated, you wouldnt refer to it as a fast.
I don't even know what you are talking about regarding overeating fat. My experience is just cut out the grains and sugars and eat whatever else you want. If you crave fat, then you eat it. There is no overeating involved. That is the entire point, if you keep your carbs low enough you do not want to overeat anything. There is no self-control involved, in fact you need to sometimes force yourself to feel like eating for social/etc reasons.
There is also no need to purchase "fancy fats", you do probably have to prepare your own food though since sugar is added to everything prepared for you.
>"All these diets ignore the most recent scientific discovery - epigenetics!"
This is hardly recent, and while I'm sure it has some sort of relationship to a persons optimal diet, no one has any idea what that is.
All I did is stop eating bread and preparing my own food so there was no sugar in it. So this extreme diet you are talking about seems like a strawman to me.
>"people should eat quality foods aligned with their genetic and epigenetic profile"
No one knows what this would be.
> "Don't eat too much carbs, don't eat too much fats, don't eat too much meat"
Which your body lets you know via a satiated feeling without gaining undesirable weight. "Too much carbs" seems to be over 50-100 g/day for most people. If it wasn't, they wouldn't eat more than was healthy.
An all meat diet is perfectly healthy if it includes enough fat. You started off by saying that you can’t get anything but energy from fat and that you need more than energy to survive.
> You cannot get "macros" from fat - you get energy, but you need more than energy to survive.
That’s not true. If you eat fat as part of an all meat diet you’ll have enough energy and nutrition to survive without problems. I wouldn’t be too surprised if a diet that was mostly fat with some lean meat worked as well.
> If you don't get carbs, your body breaks muscle tissue to produce it. There's also evidence that muscle is burned first before fat deposits.
Neither of these are true either. If you’re fasting and you stop exercising you will lose muscle rapidly as it gets broken down but if you continue exercising you’ll lose fat and a very small amount of muscle, accelerating over time.
> Ketotards eat a huge amount of fat thinking they are providing nutrients. Yes, you need fats, just like you need carbs, but not in excess.
If you’re eating nothing but meat you do in fact need fat to get enough nutrients. Given that carbohydrates are unnecessary to a healthy diet and meat is also unnecessary any notion of excess that claims to be acultural is ridiculous.
> Meat has vitamins and minerals, too. I'm not against meat, I'm against overeating when you're 30+.
This is the first time you’ve mentioned age or overeating. Every statement of fact you’ve made has been wrong. What was the point of taking part in this discussion?
Anyway, I keep saying - surviving and thriving are two different things. I want to thrive, not just to survive. I get tired of people giving the Inuit as an example. Yes, they survive on predominantly fatty meat (although they eat starchy roots, too, okay, "ate" as they've modernized), but I don't want to be anything like them, sorry, no offense! There are many tribes who are healthier, look better, and eat plenty of starches! Here's a recent article [1] about a tribe, which loads on starches, and looks and functions better than the Inuit. :D
Food is information. Eating high-fat may give some immediate results, but we have no idea what's the effect in long-term - nobody has such diet, sorry!
Also, cite a study claiming that carbs are not necessary for health? You're making a mistake again and again - just like fats carry other nutrients such as vitamin K, D, etc., carbs also come in concert with many others. It's 2018 and it's clear to all camps that refined foods are empty. I'm not asking you to eat refined tapioca starch, I'm telling you that you should eat sweet potatoes, yams, beans, legumes, etc. Of course, there's no perfect food and many plants have natural anti-nutrients just like meat and dairy do, but, again, we've evolved to handle lectins and others decently not to mention that many cooking practices also evolved unknowingly to reduce the toxicity.
I am surprised that nobody here argues an obvious detriment of carbs - their role in the formation of endogenous AGEs (advanced glycation endproducts), but, of course, for their formation, you need protein, too. At the same time, animal products are rich in exogenous AGEs [2].
[1]: https://www.unilad.co.uk/life/life-of-indonesian-tribe-in-re...
[2]: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3704564/
So 100g of carbs seems like a reasonable number if you want to be sure that your subjects do not enter ketosis.
http://www.mendosa.com/stefansson1.htm
http://www.mendosa.com/stefansson1.htm
http://inhumanexperiment.blogspot.com/2009/09/two-brave-men-...
Given an average human consumption of 2250 calories per day, they're telling us that we could feed ~10% fewer people if we moved to a fat-based diet globally?
Hall's research focus is on mathematical metabolism models, so his critique comes from that angle: it is possible doubly-labeled water measurements of energy expenditure may behave differently in a lower-carb environment, so the observed EE difference may not be meaningful. Ludwig actually briefly addresses this in their published paper, citing a few other studies suggesting that DLW is accurate and carb intake does not mess with isotopic measurements.
Hard to tell if this is a meaningful advance for the low-carb crowd, or just an artifact of insufficiently validated methodology.
The second phase of the study involved breaking the participants into three groups. They were fed the same number of calories. Each group had several biomarkers tracked. This included daily calories burned and ghrelin (a hormone) levels. I understand the critique targets the measurement of calories burned, via the doubly labeled water measurement of the metabolic date.
What I wonder is what the average weight change was for each of the three groups after 5 months. If the claim is that the high-fat diet group burned an average of 250 calories more, then that should be reflected in an additional weight loss of about 10 pounds (250 calories per day * 5 months * 30 days in a month / 3700 calories in 1 pound of fat). This would be because all the people across all groups were fed the same number of calories. If one group used 250 calories more per day, these extra calories had to come from somewhere. They would have to come from fat stores and muscle tissue inside of the body, resulting in a weight loss.
If the weight loss for that group correlates with the doubly labeled water measurement then it gives more credence to the study's results. If it does not correlate with weight loss, it is suspicious to claim that one group of people burned 250 more calories than the other over 5 months while eating the same number of calories but did not lose any weight.
It is interesting that the study authors highlight the higher energy expenditure as an advantage for weight loss, but do not seem to directly address that they did not observe this advantage during the 20 week study period.
[1] https://twitter.com/YoniFreedhoff/status/1062762047677571079
Studies have already shown that weight loss affects metabolic rates.
From the paper: "During the test phase, participants’ energy intake was adjusted periodically to maintain weight loss within 2 kg of the level achieved before randomization."
A key part of the study was that they fed the participants more or less each day to maintain weight.
In other words, there should not have been any weight change at all, as weight change would have confounded the results since weight loss is known to effect metabolism.
However, from a layman perspective, it seems like it would be nice to be able to collaborate the measure of increased metabolism not only through one method (doubly labeled water) but also through weight loss over time.
It's like having an inaccurate measuring stick and basing the results of a study solely on measurements made by that one stick, while at the same time making an effort to make sure that no other means of measuring exist.
I've also tried it for years as well to lose and keep weight down. But it's actually not healthy for you. You're better off eating a balanced diet, not too much of it, and exercising.
So, a non-profit funded by a gentleman who advocates for low-carbohydrate diets found that low-carbohydrate diets are good for you.
That just don't sound like an unbiased study.
The study looks well run. Because someone paid for a study does not automatically make it biased.
Everyone has biases. In the classic sense, attack the argument and not the debater.