It's not as simple as that IMHO. Your body uses calories from different sources differently. It's not just about energy in, energy out, that's too simplistic. In order to burn fat your body needs to not have ready access to blood glucose for energy. As an extreme example, if you ate 600 cals of sugar a day as opposed to 600 cals of protein, your body would have ready access to fuel and so would not need to burn it's fat stores. Eating the protein would mean that the body would need to convert the protein into glucose (using energy to do this) and would need to look to it's fat stores for energy.
Whilst low carbing I ate a very high calorie diet yet still managed to lose two stone in two months.
But you would burn more energy if you ate high protein foods because you need energy to convert them to glucose in addition to other body processes. Whereas eating simple sugars would mean you wouldn't need to break them down as much therefore using less energy?
Scientific research says otherwise.
Biochemistry is an immensely complicated science, but the Laws of Thermodynamics still apply. You cannot create energy so if you're only consuming 600kcal per day and your maintenance is 2000kcal per day the defect has to be made up by your body's energy store, regardless of whether the 600kcal is coming from carbs or protein.
Eh, no it doesn't. Thermodynamics is one theory of how the body uses calories, there are plenty of studies that counter claim calories in vs calories out.
The aim of VLCDs is to put you into ketosis, you only enter ketosis when glucose is not readily available. We are not mathematical formulas and neither are we made of pure energy.
By all means eat 600 cals of carbs a day, you will lose weight, 600cals are not very many but you'd have better losses and be healthier eating 600 cals of protein and fat.
I'd hazard a guess that I'm a little more familiar with the research and biochemistry in general than you (the clue is in my username).
Mass and energy are equivalent.
This is called the thermic effect of food (TEF). Protein does indeed have a higher TEF than fat or carbs. Very simply, up to 30% of protein calories ingested are used to process the protein whereas up to 10% of fat and carb calories are used for processing.
However the effects of this on weight loss are insignificant. For example, 1000kcal of protein vs 1000kcal of carbs would result in a difference of just 233kcal TEF - there would be a difference of a pound after about 15 weeks. There are other reasons too, too complicated to get into here, but here's one: Proteins are not all the same - some are much longer than others requiring more energy to breakdown. Conversely some are much shorter, requiring less energy to breakdown. The 30% TEF is an average. And thermodynamics still applies - weight change is still down to energy taken in vs energy used.
Really, do you think that giving yourself that name will make other people defer to your opinion on all matters biochemical? Please.
I have no interest in debating this topic to be honest, I did at one time but you can read it all over the net, it never get's resolved. At calorie levels as low as 600 then it probably makes little difference but all I know is I can eat a vast amount of calories on a low carb diet and drop stones. If I practically starve myself on a high carb low fat diet I really struggle to shift anything. Same as eating lots of saturated fat is supposed to give my high blood pressure, increased cholesterol, poor diabetic control, blah, blah, blah when the opposite of that is true.
Read the studies by all means, but there aren't too many out there that you can rip apart the methodology. I followed lot's of the established 'truths' for years, didn't do me any good.
I had a feeling you might come back with that, totally irrelevant to us as biological beings.
Sorry to get picky here but i thought 3500 calories was equal to 1lb?
Therefore 15 weeks making a difference of 233 cal a day every day would be more like 24,465 = 7lb? I think if this is right then it's great that i can lose 7lb of extra weight in 15 weeks by eating an extra 233 cal a day (assuming pure protein).
haha mine too... i never thought id get this reply so i guess the answer is yes. calories are all that matter!