Nonequilibrium thermodynamics and energy efficiency in weight loss diets, by Richard D Feinman and Eugene J Fine.

From http://www.caloriegate.com/the-black-box/9-pictures-that-prove-beyond-a-reasonable-doubt-that-calories-dont-count

From Nonequilibrium thermodynamics and energy efficiency in weight loss diets:-

"Conclusion
Emphasis on kinetics and nonequilibrium thermodynamics provides a conceptual framework for understanding the effect of macronutrient composition on maintenance and change of body mass and possibly for analysis of adipocyte metabolism in general. The simple model presented is intended to be consistent with a general shift away from equilibrium thermodynamics and towards a more dynamic analysis of cellular processes."

Sounds plausible. There's only one thing wrong with Feinman et al's article - it's completely wrong!

Consider two rooms:-

Room "A" has an adjustable heater. The heater is adjusted until the room temperature is 20°C.

Room "B" has a radiator, controlled by a wall-stat set to 20°C. The radiator is on, and the room is at 20°C.

We have two rooms of the same size, at the same temperature.

If you plug in & turn on a 2kW fan heater in each room, what happens to the temperature in each room?

Room "A" gets warmer, because there is 2kW more heat power entering it.

Room "B" stays at 20°C, because the wall-stat reduces the heat power from the radiator by 2kW.

The human body stays at 37°C ±~2°C, because there's a Negative Feed-Back loop adjusting the heat power produced, via UCP's, futile cycles, thyroid hormones, shivering and heat conservation/wasting behaviours.

∴ Variable heat power generation due to variable Dietary Efficiency doesn't change E_out.

EDIT: By request, here's Figure 1 from the above study.

This suggests that fat mass & therefore weight can increase indefinitely - at maintenance energy intake, due to the effect of insulin on HSL. This, of course, is quite impossible!

From The Energy Balance Equation:-

Change in Body Stores = E_in (corr for digestion) - E_out (BMR/RMR + TEF + TEA + SPA/NEAT)
__BMR/RMR & TEA ∝ weight
∴ ↑ weight → ↑ E_out
__If E_in = constant, ↑ E_out → ↓ (E_in - E_out) → ↓ weight
∴ ↑ weight → ↓ weight
∴ Figure 1 is wrong.

Why Calories count (where weight change is concerned).

I have to add the words "where weight change is concerned", as calories have little to do with body composition or general health (unless somebody becomes morbidly obese).

From https://docs.google.com/file/d/0Bz4TDaehOqMKSXZHUUVxWnl5VTQ/edit?usp=sharing

Arguments used by Calorie Denialists include:-

1) Calories don't count because the human body isn't a Bomb Calorimeter and treats different macronutrients differently.
 
100g of liquid paraffin burns in a Bomb Calorimeter, yielding 900kcals. In a human, it passes through completely undigested. Ah-ha!, I hear you saying. This proves that the Energy Balance Equation is invalid. Uh, nope!

Calories in = Calories entering mouth - Calories exiting anus

As 100% of liquid paraffin calories entering the mouth exit the anus, Calories in = 0

This is why Sam Feltham's "Smash the Fat" "experiment" is nonsense. A high percentage of the large amount of raw almonds he ate would have exited his anus incompletely chewed, undigested & unabsorbed.

See the picture above? In the late 1800's, W.O. Atwater established Atwater Factors (3.75kcals/g for digestible Carbohydrates, 4kcals/g for Proteins, 5kcals/g for Ketones, 7kcals/g for Alcohols & 9kcals/g for Fats*) using Human Calorimeters, not Bomb Calorimeters. Atwater Factors are pretty accurate.

*Fats containing different fatty acids have slightly different kcals/g. Fats containing long-chain fatty acids are 9kcals/g. Fats containing medium-chain fatty acids e.g. coconut oil are ~8kcals/g.

For more information, see Calories ...


2) Calories don't count because Dietary Efficiency varies for different macronutrients.

Uh, nope! The Heat Power generated by the body is regulated by a NFB loop involving the Hypothalamus, Pituitary, Thyroid Axis, also Uncoupling Proteins (UCP's), also shivering, so as to maintain a body temperature of 37°C ±3°C. If this wasn't the case, different amounts & types of foods (also, changes in ambient temperature & clothing) would cause large variations in body temperature resulting in death, as the enzymes in our bodies function correctly over a limited range of temperatures.

Heat Power generated by the body (W) = Temperature difference between the body & ambient (°C) divided by Thermal resistance between the body & ambient (°C/W)

∴ Dietary Efficiency is irrelevant.

How low-carbohydrate diets are (incorrectly) explained to work.

Having explained how low-carbohydrate diets work, here are a few ways in which they don't work.

Uh, nope!

1. Hormonal clogs: This is a term used by Jonathan Bailor. I don't think he's referring to wooden shoes! The "clog", I'm guessing, is supposedly caused by that dastardly hormone insulin. Uh, nope!

See the following plots of RER vs exercise intensity after being on high-fat diet or low-fat diet.

RER = 0.7 ≡ 100%E from fat. RER ≥ 1.0 ≡ 100%E from carb.

The low-fat diet results in higher RER, so the body is burning a higher %E from carb and a lower %E from fat.

However, this doesn't make any difference to weight loss, as it's merely a substrate utilisation issue. In addition, when the body is burning a higher %E from carb, this depletes muscle glycogen stores faster, which lowers RER during the course of the exercise. So, it's not a problem.


2. Insulin: This is Gary Taubes' hypothesis. Insulin makes your body store carbohydrates as body fat. Uh, nope!

The only time that there's significant hepatic DNL is when there's chronic carbohydrate over-feeding. If you eat sensibly, there's no significant hepatic DNL.


3. A Calorie isn't a Calorie, where weight change is concerned: This is Richard D Feinman's hypothesis. "A calorie is a calorie" violates the second law of thermodynamics, therefore there's a metabolic advantage with low-carbohydrate diets. Uh, nope!

Where to start? Evelyn Kocur knows her Physics, so I'll start there. See The first law of thermodynamics (Part 1) and The first law of thermodynamics (Part 2).

From Second Law of Thermodynamics:-
"Living organisms are often mistakenly believed to defy the Second Law because they are able to increase their level of organization. To correct this misinterpretation, one must refer simply to the definition of systems and boundaries. A living organism is an open system, able to exchange both matter and energy with its environment."

People on ketogenic diets excrete very few kcals as ketone bodies. See STUDIES IN KETONE BODY EXCRETION. There is no significant Metabolic Advantage with low-carbohydrate diets.