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Get startedNew major study: A calorie is not a calorie
in Calorie counting, Dr. David Ludwig, New study, NuSI, Weight loss 
Despite what the sugary beverage and processed snack food companies want us to believe, all calories are not created equal.
A new study from Harvard shows that individuals following a low-carbohydrate (20% of total calories) diet burn between 209 and 278 more calories per day than those on a high-carbohydrate (60% of total calories) diet. So the type of calories we eat really does matter.
The New York Times: How a low-carb diet might help you maintain a healthy weight
This isn’t the first study to investigate this topic, but it is likely the best.
The current study was a meticulously controlled, randomized trial, lasting 20 weeks. Even more impressive, the study group provided all the food for participants, over 100,000 meals and snacks costing $12 million for the entire study! This eliminated an important variable in nutrition studies — did the subjects actually comply with the diet — and shows the power of philanthropy and partnerships in supporting high-quality science.
After a run-in period where all subjects lost the same amount of weight, participants were randomized to one of three diets: 20% carbs, 40% carb, or 60% carbs, with the protein remaining fixed at 20%. Importantly, calories were adjusted to stabilize weight and halt further weight loss, thus making it much more likely that any observed difference in calorie expenditure was not from weight loss, but rather from the types of food consumed.
After five months, those on the low-carb diet increased their resting energy expenditure by over 200 calories per day, whereas the high-carb group initially decreased their resting energy expenditure, exposing a clear difference between the groups. In addition, those who had the highest baseline insulin levels saw an even more impressive 308-calorie increase on the low-carb diet, suggesting a subset that may benefit even more from carbohydrate restriction.
Why is this important? It shows why the conventional wisdom to eat less, move more and count your calories is not the best path to weight loss. Numerous studies show better weight loss with low-carb diets compared to low-fat diets, and now studies like this one help us understand why.
Our bodies are not simple calorimeters keeping track of how much we eat and how much we burn. Instead, we have intricate hormonal responses to the types of food we eat. It’s time to accept this and get rid of the outdated calories in-calories, calories-out model, thus allowing for more effective and sustainable long-term weight loss.
Additional coverage of this dramatic new study:
LA Times: The case against carbohydrates gets stronger (by study author Dr. David Ludwig)
The Times: Low-carb dieters “shed more weight”
MedPage Today: Low-carb diet wins for weight maintenance
Earlier
Cutting calories won’t solve your weight issues – do this instead
Is low carb the best treatment for reversing diabetes?
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Low Carb is helping me in another way though. Having gained a few pounds due to my illness-induced sedentary lifestyle, I am now pleased to note the scales gradually dropping back to a healthy weight for my height. I wasn’t really expecting to loose weight, because I was eating LC to satiety, and thinking only of making the transition to the new way of eating. Yet there it is, I am down about 18lbs in 7 months, bringing my BMI to 24.
This is so simple. No need to count calories. No feelings of hunger, or deprivation. And after the first few adjustment weeks, I’ve no urge to eat sweet stuff. I never thought I would become so relaxed about turning down desserts!
Another thing. Before LC, I always really felt the cold. Now I’m eating LC, this is much less of an issue. Perhaps that increased metabolism mentioned in the article accounts for my new found warmth? Lots to think about, but I’m sure happy to keep eating this way.
Thanks Diet Doctor. :)
Although certainly interesting, the results of a study like the one reported here are woefully incomplete. We loose a lot information when we treat all members of a group as being physiologically equal to their statically computed "average" member. We could learn so much more from a similar (albeit three times as expensive to run) study that observed every subject under all three test conditions. We almost certainly would find that some individuals would fare better in each of the three test conditions than in the other two, especially if we were measuring more than simply the number of calories "burned" and assessed other quality of life and health measures such as their motivation to get physical exercise, their mental acuity (as opposed to "brain fog"), and their levels of chronic pain.
Also, besides a "calorie" not necessarily being a true calorie in terms of its energy contribution, I think we also would need to look more closely at the fact that "a calorie from carbs" is not just "a calorie from carbs." It also varies a lot according to the type of carbs (e.g. simple/refined vs. complex, or glucose vs. fructose which are metabolized entirely differently) not only in terms of how our bodies process and utilize them, but also in terms of how they affect our gut microbiome.
The bottom line is, rather than just blindly following the "dictates" of some kind of "scientific" finding in terms of what constitutes a healthy diet, each of us ultimately really needs to experiment around and find out what kind of diet works best for ourselves as unique individuals.
Different foods affect differently how body utilizes fats, carbs and protein.
By eating high processed carb diet you get fatter because more calories is stored because more insulin is released, compare to whole food low carb diet. Not because "calorie is not a calorie".
Our bodies are very complex system. Counting calories from food we consume and then use some empirical number to multiply with our body weight to analyze the energy flow in our bodies is way to simplistic, especially for obese sick people, who's metabolism is really damaged.
As far as i know from google and every nutrition plan/guides, all the presentations i saw on these website and youtube channels, it says that fat and carbs are mainly used as energy source, but protein is mainly used to build muscles and other body parts.
Then question is: Why do people count the protein they eat as calories consumed (4 kcal/g), when its used as building material?
In Dr. Ted Naiman's "Too much protein is better than too little" presentation you can see that people who ate more protein lost more weight compare to lower protein diet (diets were "isocaloric"). According to basics of fats, carbs and protein knowledge these diets are not isocaloric, unless you burn them in fire, but as we know protein is not burned for energy primary in human body, but rather is used as building material. So people, who ate the higher protein diet, ate less energy, a.k.a. calories (carbs and fats), and to get energy for body needs they burned stored energy (aka mainly stored body fat), thus leading to bigger weight loss. This makes more sense (thou this is just my thoughts just using logic and the knowledge i have), than saying "calorie is not a calorie", which doesnt tell anything how our body works.
One way of countering the assertion that "a calorie is a calorie," meaning that potential calories eaten has to equal calories either burned or stored as fat, would be to say, "No, that's simply not true." But using casual English language in a conversation it's easy for me to mean just exactly that and nothing more by saying "No, a calorie is NOT a calorie." Of course a calorie as defined by physics is a calorie as defined by physics. But when you hear the words "a calorie is not a calorie" your mind apparently represents that statement in what I believe is too literal a sense. When I hear those same words, my mind just automatically skips over the unintended literal interpretation and goes directly to the intended meaning of it, much like what happens when I hear someone unintentionally or even intentionally use a malapropism. If I notice it at all I just get a quick chuckle out of it and move on. We are just using casual conversational English here, which often is not as strict as what would be expected in a peer-reviewed journal article. We are a growing community of people from all walks of life and levels of education, and our goal is to share information and ideas in ways that pretty much anyone can understand, without quibbling over each other's exact choice of words.
I also have always had suspicion since I was in highschool that big food companies and big agriculture somehow influenced the food chart/pyamid.
Explain why you think the study is poorly designed. Explain how you think the study would be precise and accurate. Explain the conclusion you take away from the data gathered in this study and why it doesn't prove it's hypothesis.
Study is interesting however results do not mean either diet plan was superior.