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.

Dietary Carbohydrate restriction as the first approach in diabetes management. Critical review and evidence base, by Richard D Feinman et al.

Another Bookmarking post.

From http://dgeneralist.blogspot.co.uk/2013/11/the-low-carb-high-fat-diet.html

The study in question is Dietary Carbohydrate restriction as the first approach in diabetes management. Critical review and evidence base. Here are my comments on the 12 points.

Point 1 is wrong. For ~85% of people who have T2DM, hyper*emia is the salient feature, where * = glucose, TG's, cholesterol, NEFAs, uric acid etc. For ~85% of people who have T2DM, it's a disease of chronic excess.

Ad lib LCHF diet → ↓ Blood glucose & ↓ fasting TG's, but ↑ PP TG's, ↑ LDL-C, ↑ LDL-P & ↑ NEFAs. See Postprandial lipoprotein clearance in type 2 diabetes: fenofibrate effects.
↑ PP TG's is associated with ↑ RR of CHD.
↑ LDL-P is associated with ↑ RR of CHD.
↑ NEFAs are associated with ↑ RR of Sudden Cardiac Death.

Point 2: So?

Point 3 is wrong. A caloric deficit is essential, to reverse liver & pancreas ectopic fat accumulation. See Reversing type 2 diabetes, the lecture explaining T2D progression, and how to treat it.

Point 4 is misleading. Feinman doesn't distinguish between different types of carbohydrates. Starches, especially resistant starches (e.g. Amylose) are beneficial. See Point 11.

Point 5 is moot. Prof. Roy Taylor found that motivation determines adherence. Prof. Roy Taylor's PSMF was adhered to. See Point 3.

Point 6 is correct. Prof. Roy Taylor's PSMF is ~1g Protein/kg Bodyweight, some ω-6 & ω-3 EFAs & veggies for fibre. See Point 3.

Point 7 is misleading. Siri-Tarino et al gave a null result by including low fat studies, also a dairy fat study which had a RR < 1 for increasing intake. Chowdhury et al gave a null result, as some fats have a RR > 1 for increasing intake and some have a RR < 1 for increasing intake.

Point 8 is irrelevant. ↑ Dietary fat → ↑ 2-4 hour PP TG's. See Point 1.

Point 9 is partly correct. Microvascular, yes. Macrovascular, no. See Point 8.

Point 10 is mostly irrelevant. See Point 8.

Point 11 ignores results obtained with high-starch diets, where the starch contains a high proportion of Amylose. See Walter Kempner, MD – Founder of the Rice Diet and From Table to Able: Combating Disabling Diseases with Food.

Point 12 is misleading. The low-carbohydrate part is fine. It's the high-fat part that can cause problems. See Point 8.

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.

Bray et al shows that a calorie *is* a calorie (where weight change is concerned).

Continued from Everyone is Different, Part 3.

EDIT: I made an error in stating that all of the extra calories came from fat, in the fat overfeeding phase. Thanks to commenter CynicalEng for pointing that out. It doesn't change the conclusion at all.

At 01:17 on 6th June, during a Facebook discussion, Fred Hahn told me:-
"Nigel Kinbrum - read this please.
Bray, et al. Shows that a Calorie is Not a Calorie and that Dietary Carbohydrate Controls Fat Storage.
Perhaps you'll learn something from a real expert who teaches metabolism to medical students at the largest medical school in the country."

So I did.

At 02:22, I replied:-
"Thanks for that. I read Feinman's blog post about Bray et al http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3777747/ some time ago.
There's a fundamental error in Feinman's analysis. As LeonRover pointed out in his comment http://feinmantheother.com/.../bray-et-al-shows-that.../...
In Diets:- "Absolute carbohydrate intake was kept constant throughout the study."
Also, in COMMENT:- "The extra calories in our study were fed as fat, as in several other studies, and were stored as fat..."
Oh, whoops! That may be why it was rejected by the editor."

Here's Figure 6 from Bray's study.

From http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3777747/

Some Definitions:-

LBM = Lean Body Mass
FM = Fat Mass = Body Fat

Weight change = (LBM change + FM change)

Weight change varies from ~+3.5kg (@ +2,500kJ/d) to ~+9.1kg (@ +5,900kJ/d).

(Maximum weight increase)/(minimum weight increase) = 2.6
(Maximum kJ/day increase)/(minimum kJ/day increase) = 2.36

∴ A calorie *is* a calorie (where weight change is concerned) ± some inter-personal variation.
∴ Insufficient protein can result in LBM loss (this is bad).
As LBM has a lower Energy Density (~400kcals/lb) than FM (~3,500kcals/lb),  LBM loss can increase weight loss, when in a Caloric Deficit.
See The Energy Balance Equation, for a simple explanation, and The Dynamics of Human Body Weight Change, for an incredibly complicated one!


I was rather chuffed when Alan Aragon left the following comment at 04:34:-
"Nigel is correct. From Bray et al's text:
"The extra calories in our study were fed as fat, as in several other studies [33,34], and stored as fat with the lower percentage of excess calories appearing as fat in the high (25%) protein diet group. The higher fat intake in the low protein group probably reduced nutrient absorption (metabolizable energy) relative to the other groups and this would have brought the intake and expenditure closer together in this group.""

Feinman has deleted his blog post. However, his post I Told George Bray How to do it Right is still there. I believe that Dr. George A. Bray M.D. sort-of did it right.

Dr. George A. Bray used a "weight maintenance formula" in all three groups for the weight maintenance phase. He then changed the formula in all three groups to low-P, med-P and high-P formulas, for the fat overfeeding phase. Carbohydrate grams remained constant in all three groups for all phases, but additional fat grams were fewer in the high-P group than in the low-P group, for the fat overfeeding phase.

I would have used the low-P, med-P and high-P formulas for the weight maintenance phase and for the fat overfeeding phase, to equalise the additional fat grams in all three groups.

Continued on Everyone is different Part 4, Fallacies and another rant!