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How many calories on a low carb diet?

Since I've been watching my carb intake my appetite seems to have disappeared. I struggle to think of what to eat as I'm not that bothered. Certainly don't wait for mealtimes any more. I am losing weigh slowly but they do say that the more carbs you eat the more you want and that seems to be true as far as I am concerned any way.
 

I'm in the middle of trying to read Gary Taubes's enormous tome "The Diet Delusion" and have just read through the section where he talks about researchers using statements about the FIrst Law of Thermodynamics as a means of avoiding a scientific investigation of the notion that low fat diets might not be the best way to lose weight. To be honest, what he says about the First Law is a little confusing - and I don't think it is very well written.

We should all remember that the FIrst Law of Thermodynamics is about conservation of energy - not about gaining or losing weight. The FIrst Law, in its simplest form says that the change in energy in a system is equal to the energy added to the system minus the energy lost by the system. It simply is not true that this mandates an increase in weight for a system that gains energy. A simple (fictional) example will, I hope, clarify what I am trying to say here ......

I have a shed in the garden. Amongst lots of gardening tackle, cans of paint & other rubbish, I kept about 100kg of timber logs in the shed. The calorific value of the timber is 14,700 kJ/kg - so the 100kg that I store there has an energy content of 1,470,000 kJ (equivalent to about 350,000 food calories). As it stopped raining this morning, I decided to do a bit of tidying up. I removed the 100kg of wood from the shed and built a bonfire with it that I will light this weekend. I did some tidying in the garage too. I remove three 20 litre jerry cans full of diesel that I bought some months back when some clown government minister said something daft about fuel shortages and it being sensible to stock up. I put the jerry cans in the shed. They weighed a total of 50kg (excluding the cans themselves). Now, diesel has a net calorific value of 43,400 kj/kg - so my three jerry cans contain 2,170,000 Kj (equivalent to 516,666 food calories).

So what happened here? Well, I added 516,666 food calories to my shed and removed 350,000 food calories - so to satisfy the First Law, my shed must now contain 166,666 more food calories than it did before (it's had a humungous meal!!). So, did my shed gain weight? No, not a bit of it - I added 50kg but removed 100kg. It got 50 kg lighter!!

After reading much of Gary Taubes book and thinking about the implications of the FIrst Law of Thermodynamics, I came to the conclusion that any nutritionist or diet researcher who quotes the FIrst Law of Thermodynamics at you, as a justification for rubbishing the results of trials that conflict with his (or her) preconceived notions is, at best, guilty of wooly thinking and at worst .............

Andrew
 
I'm new to LCHF eating so I did my research before I ate anything and looked at the carb content only before I ate anything. I then started testing my blood before and after meals to see what carbs make my BS high and I removed them all from my diet - bread, pasta, rice I just can't eat without getting sugar spikes. So to make life easier I just removed them.

I've definitely overdone the protein eating in the first few weeks because I was afraid of feeling hungry without carbs so I dished out more protein than I actually needed and now, after a few weeks my body is telling me I can eat much less protein than I thought at first. So yes, the body will eventually regulate the appetite and no, we don't need to count calories, eat protein and fats freely and you'll soon find your own levels. But definitely keep a close eye on the carbs and how they affect you.

I've lost just over 2lb since I started stuffing my face and I'm 98% sedentary at the moment due to other health issues I have going on.
 

Hmmmm, not sure I agree. Human bodies store excess energy as fat (the capacity for glucose storage as glycogen is very small). One lb of fat contains about 3500kcal. If you eat more 3500kcal more than your burn in a given time period, then you'll put on about a pound of fat (plus some water weight).


But your shed can only store big vats of pig fat (actually it can store a small pile of sugar cubes too, but compared to the pig fat vats, these store a trivial amount of energy).

Your body contains less than 5000kcal of glucose (in your liver, blood and muscles). 5000kcal = 1.2kg of glucose in total. So if you emptied your glucose tank then you'd only lose about 2.5lbs total.


I agree. His point, and my point is that the First Law is statement of fact, but it doesn't tell you anything about what is regulating the "energy in" (appetite) and "energy out" (exercise). The first law just tells us that we will put on weight if we eat more than we burn. It doesn't tell us why we put on weight.
 
Patch said:
There you go, Sue - a nice, concise answer! :crazy:

My opinion is - don't count the calories. Eat until you're full. When you're not eating loads of carbs, you'll know when you're full.
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That is so true Patch. When I ate carbs with my meals I would feel full but after 15 minutes I'd feel hungry again, yet my tummy was still full of food. Very weird feeling full yet hungry at the same time.

No that I've removed carbs and eat only protein and fat, I feel full for longer. Sometimes I look at the clock and think "I should be ready for my next meal but I don't actually feel hungry yet", and that is totally weird for me. I'm now eating less protein because I don't want to overstuff myself when it's not necessary. So I'm really learning to balance out the quantities that I eat now too.
 

YES! That's exactly what governs your appetite. Your body expects to get fat alongside protein (as if you were eating a dead animal). It's much easier to eat a big juicy steak (with lots of fat) than it is to eat a dry chicken breast (which is essentially pure protein).

"So yes, the body will eventually regulate the appetite and no, we don't need to count calories, eat protein and fats freely and you'll soon find your own levels". Brilliant analysis. I agree completely.
 

Oh Dear God :roll: ... please save me from having to eat dry chicken breast in order to become slim. It stuck in my throat when I was a kid and I'm now 59 years of age and still haven't got my head round why anyone would want to eat chicken breast unless it's covered in crispy skin, smothered in gravy or a rich sauce. I really don't believe chicken breast was created to be eaten without any of those things. So please forgive me for preferring the nice juicy thighs complete with skin.
 

No more Filet Steak in my house. I go for the fattiest bit of Ribeye I can find. Fatty meat tastes good as a result of 200million years of evolution. Skinless chicken breasts are an aberration.
 
borofergie said:
The first law just tells us that we will put on weight if we eat more than we burn.
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The FIrst Law of Thermodynamics is about energy and says nothing about weight. It says that if you add more energy to a system than you remove then that system will contain more energy. The conclusion about adding weight is your own - and you have yet to justify it.

Andrew
 
phoenix said:
So what happens when calories* decrease on a nationwide basis and that reduction comes mainly from from protein and fat with an increased dependence on sugar and refined carbohydrates ?
Guyanet writes on it here.
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What happens when calories increase on a nationwide basis, and the increase comes mainly from carbohydrate?



Something like this?
 

Yaaaaaaaaaay! A fellow fatty ribeye lover! I just love my ribeye steak simply grilled or fried and just seasoned with salt and pepper. I don't adulterate it with any other herbs or spices because it really doesn't need them, I love to see it just sitting there on my plate in all it's well deserved glory, complemented only slightly by a few fried mushrooms in a little cream and French mustard sauce and a side salad of thinly sliced tomato and cucumber with a dash of sour cream. Bliss.

Not something I would have or even want every day but once a week is quite enough because it's THAT satisfying.
 

Your body stores excess energy as fat. The calorific value of fat is 9kcal/g

Therefore ΔW=ΔE/9=(Ein-Eout)/9

The Second Law says that there will be some system losses, and obviously you have to account for waste matter in Eout.

Unless you are arguing that there is an significant alternative storage mechanism or that the calorific value of fat is not a constant, then ΔW∝ΔE.
 
Patch said:
There you go, Sue - a nice, concise answer! :crazy:

My opinion is - don't count the calories. Eat until you're full. When you're not eating loads of carbs, you'll know when you're full.
Click to expand...

Maybe we should all get together and devise a Carboholics Anonymous 12 Step Programme ... and we should all announce ourselves by saying ...

"Hello Everyone, my name is ... and I'm a Carboholic."

I think by virtue of being human and having a brain, we can become addicted to ANYTHING at all. Life itself is an addiction in a way. Anything habit, good or bad, that we find hard to break, is an addiction. We can be addicted to heroin or addicted to exercise. We can be addicted to alcohol or addicted to carbs. The substance or activity doesn't really matter, it's how it makes us feel that we're really addicted to. Some people are even addicted to feeling yukky, because they can't envisage feeling any other way, their way of eating brings the same yukky results yet still they keep eating that way out of habit.

I didn't realise how addicted I was to carbs. I knew that once I had been addicted to sweets and cigarettes and I had one hell of a job getting myself off both those nasties. But I didn't consider myself addicted to bread or cakes or pastries, until my stomach started yelling at me to STOP!

But once I DECIDED to stop eating sweets by the bagful and stop smoking, I mean REALLY DECIDED, I was able to stop and I've never wanted either of those things again. I have the occasional sweet but don't enjoy them and realised I really never did. Cigarettes, since the day I smoked my last one 18 May 2002, I can honestly say I've just never even noticed them again. I never seem to meet any smokers, and the thought of me with a cigarette in my mouth now seems like it was all happening to another person. We can never TRY to give up or stop doing anything, because trying doesn't cut it. We have to DECIDE because it all happens in the mind first. The body just follows the leader.
 
borofergie said:
Your body stores excess energy as fat. The calorific value of fat is 9kcal/g
Therefore ΔW=ΔE/9=(Ein-Eout)/9
Click to expand...

That is just school-boy maths - and should perhaps be prefaced by "all other things being equal". Can you cite any real published studies that substantiate that human bodies actually behave in such an idealistic fashion? There are references in the Gary Taubes book to several studies that give inconsistent results, such as folk gaining weight when eating less and the converse. Unless you can explain the reason for such inconsistent results then you are simply kite flying.

The Second Law says that there will be some system losses, and obviously you have to account for waste matter in Eout.
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I don't see that the Second Law of Thermodynamics has any relevance to "system losses", whatever you mean by that. For those who don't know, the Second Law states - "The entropy of an isolated system not in equilibrium will tend to increase over time, approaching a maximum value at equilibrium"

As you correctly say, "obviously you have to account for waste matter". I have yet to see any serious study that has measured changes in metabolic rate and also the energy in urine, faeces, perspiration, breathing and so on whilst trialing changes in diet composition and calory content. Isn't it true that the lack of such solid science is precisely the reason why there is still disagreement about the effectiveness or otherwise of different diets??
 
Jenny Ruhl has a very good nutrition calculator for number of calories and macronutrients for weight loss and/or weight maintenance based on carbohydrate intake at her Truth About Low Carb Diets site:

http://www.phlaunt.com/lowcarb/DietMakeupCalc.php

(Hope I'm not breaking any rules by posting the link)
 

You want be to provide references that "the first law of thermodynamics" applies and that the principal mode of energy storage in humans is fat? :shock: I'm stating the conventional position. If you have some alternative theory you should probably write it down...

The First Law of Thermodynamics applies to ALL systems. How is that "kite flying"?

Give me one example of ANY system for which the first law doesn't apply and I'll take you seriously (and also applaud the Nobel prize that you'll pick soon afterwards).

The FIrst Law of Thermodynamics is about energy and says nothing about weight.
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Fat is just is the storage of chemical energy. An increase in stored chemical energy is associated with an increase in weight of the system. So of course the First Law of Thermodynamics applies.


The Second Law of Thermodynamics states that it is impossibe conversion from one form of energy to another with 100% efficiency. When you convert chemical energy "fat" or "glucose" to kinetic energy and thermal energy during exercise, energy is lost through heat rejection. To fuel 3500kcal of exercise you need to burn more than a pound of fat.

If you're going to have a dig at the First and Second laws, it would be a pity not to take on the Zeroth law while you're at it.


You haven't looked then. It's standard practice to measure the losses included in urine, feces, heat rejection and even sweat, at facilites like this one: http://www.uow.edu.au/health/healthscie ... index.html

Here is one example: http://www.ncbi.nlm.nih.gov/pubmed/3604965
But obviously there are hundreds.

In fact Atwater used bomb calorimeters to manage the energy content of feces and urine in order to calculate the effective calorific values of macronutrients.
 

That's strange. In my opinion Taubes is among the very best science writers.


Gary Taubes is not denying that First Law is relevant to weight gain or loss. His point is that it only deals with WHAT happens (energy is accumulated as stored fat) but not with WHY it happens (what is regulating the inputs and outputs to the system).

In his own words:
http://garytaubes.com/2010/12/inanity-of-overeating/

I believe in the First Law of Thermodynamics
Taubes believes in the First Law of Thermodynamics
You should believe in the First Law of Thermodynamics too...
 
I do count calories. The reason being, it has taken until pretty recently to find a way for me to eat enough +/- to make sure I have steady weight loss. When first diagnosed, many will remember Metformin decimated my appetite and a lot of days I was struggling to eat 400 calories. After the Newcastle Diet, I had shrunken tummy, and still struggled to eat enough. So, bit by bit, I fiddled around with my calories until I found a figure that worked for me. I worked out 1,500 calories a day gave me a pretty steady weight loss, I was never hungry, so stuck to that.

I finished week four of the 5:2 fast yesterday, with very low calories, and I often struggle to make the 1,500. But, I try very hard to reach that as it does help.

With diabetes I strongly think it's all personal choice. There is no right or wrong way. By Monday I will have reached normal BMI - I hope, and want to get to around the middle of the normal range. Once I do and I am maintaining, my calories will have to rise, but for now, it's working fine for me the way I am doing it. I still put carbs above calories and always will.
 
borofergie said:
Your body stores excess energy as fat. The calorific value of fat is 9kcal/g
Therefore ΔW=ΔE/9=(Ein-Eout)/9
Click to expand...

Let's try again ......... apologies for not replying earlier, I've been more than a tad busy.

You say that losing weight is straightforward, just eat less. You then cite the First Law of Thermodynamics as justification for the assertion. I hope that I do not misrepresent your position on this.

My position is simple:

* I have no issues with the First Law of Thermodynamics. All it says is that (Wikipedia definition): The change in the internal energy of a closed system is equal to the amount of heat supplied to the system, minus the amount of work done by the system on its surroundings. It is simply a restatement of the law of conservation of energy.

* It does follow from the FIrst Law of Thermodynamics that if the (chemical) energy in food ingested is different from the sum of "heat given off by the body" + "mechanical work undertaken by the body" + "the heat content of breath expired, perspiration, unrine, faeces (and anything else I've forgotten)" then there will have been a change in the energy content of the body.

* I have issues with assertions that are claimed to follow from the First Law of Thermodynamics where steps in the logic are asserted rather than proven.

* I know of no controlled study into calorie controlled dieting that has captured the breath expired, perspiration, urine and faeces of subjects to identify the change in their energy content. If you do, please let me know which one did that and I'll investigate it. If you do not, then you cannot possibly know what proportion of the energy in any additional food ingested is stored as fat (or muscle tissue or bone or .......... ).

* There is a lot of anecdotal evidence that some folks do not lose weight if they eat less and others do not gain weight if they eat more. If memory serves, there are also controlled studies referenced in the Gary Taubes book showing that the results of calorie controlled diets are inconsistent at best. This would not be so if your assertions did logically follow from thermodynamic laws.


Andrew
 
I really want to have a go at a Low Carb diet since I have tried everything else to no avail. I asked my dr the other day and she was ok me giving it a go but was not optomistic because she said you need carbs when you are diabetic which I am aware of but I need to try and know that it is safe to do.
 
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