Printable page in A4 size A Calorie is a Calorie
Richard Feinman has published articles on application of thermodynamics to nutrition.
His articles explain why the common idea that "a calorie is a calorie" is not correct. His
argument in brief: the first law of thermodynamics (conservation of energy) is a
bookkeeping law, that it does not say how energy input is divided between weight gain, work
done, heat generation or storage of energy in different biomolecules.
The second law is a dissipation law. It says that all (real) processes are inefficient.
"Feinman explained how diets of different composition vary in efficiency, in particular,
how carbohydrate-restricted diets can lead to reduced efficiency (with respect to fat
storage). How often it happens or how to control it is not known yet but once you know it
is possible to lose more weight, calorie-for-calorie;
1) there is no reason to disbelieve reports that say it happens (especially if the
experiments are well done, and these are almost always low-carbohydrate diets.
2) it is worth investing in finding out how to optimize things. There are a lot of good
books that give you practical ways to start.
It is important to say that nobody thinks that low-carbohydrate diets (of which there are many types) always have an advantage but the potential is what you want to exploit. The reason that we frequently see little difference between isocaloric diets is not because such effects are not possible but because, for similar people under average similar conditions, the body has feedback mechanisms that maintain the status quo and there will be calorie balance.
You don't have to own a metabolic chamber, to know that your intake is variable day-to-day, but your weight may be quite stable. That is due to biology, not physics. The explanation based on physics, predicts variation; food intake increases, and multiple changes of different efficiencies take place. Thermodynamics predicts variability. You just have to find a way to break through.
The effectiveness of carbohydrate restriction has been demonstrated, in animal models where there is control of the food intake, and in humans, where there are frequently big differences between the calorie intake and metabolic output. The body finds ways to "waste" energy, like running an engine with the clutch disengaged, or running hotter. The body can "conserve" energy, like using more efficient fuels such as fatty acids and ketones for instance, or by just running a little cooler.
Feinman has said that this is the bottom line: "Low-Carbohydrate diets are the safest change that you can make in your diet. You know this because after forty years of obsessively trying hard to find something wrong with it, the medical establishment has found nothing. Zero. Zilch, Zimbabwe. Since you know its safe, you can try it for a couple of weeks. If you don’t like it. Stop." The USDA and other agencies will offer you alternatives. Before you follow them, you might ask for their track record."
Richard David Feinman
Professor Richard David Feinman, is well qualified biochemist, who has studied the application of thermodynamics to nutrition, so he's interested in metabolism, in how the body creates energy from food.
On Diabetes:
Prof. Feinman's book The world Turned Upside Down: The second Low-Carbohydrate Revolution; was the second book I
read in this topic. Although the cover image depicts a light hearted approach, what the book
talks about is no laughing matter. On the topic of diabetes, Diabetes New Zealand in line
with the USA, recommends a balanced diet, "a rainbow of foods". Prof. Feinman says; "Scientifically, the burden of
proof is on anybody who would say that it is a good idea for people with diabetes to have any
significant amount of carbohydrate." ... and "If you have diabetes or metabolic syndrome,
carbohydrate restriction is the default approach, that is the one to try first."
In this 53 min video Prof. Feinman explains why dietitians keep insisting that their non-scientific "knowledge" is the "gold standard" for human diet. (Threat of expulsion from the dietician's profession, in some countries, is the price of supporting a LCHF diet.) Prof. Feinman explains why their "knowledge" is not valid, for general health, for weight loss, nor for diabetes. The science tells us that hormones control most of the "automatic" responses in the body, including how we produce energy and how we control our weight. If you can understand how insulin behaves in the body, you'll soon learn how to control your weight. "Nutrition is applied biochemistry."
"Every time you see a low-fat item in the supermarket you are looking at an artifact of one of the most bizarre stories in the history of science." ... "The most difficult part of writing this book is understanding or, again at least describing - I don't think it's possible to understand - how the whole field of medical nutrition could be so wrong."
The metabolic pathways in the body are involved in the digestion and absorption of the carbohydrates, proteins and fats we eat, and are critical in the maintenance of our health and well being. All the food you eat is broken down into constituent parts unlike the food you ate. There are essential fatty acids and essential proteins, but there is no such thing as an essential carbohydrate. You do not need to eat grains or any carbohydrate at all, to have a healthy diet as explained here. The 2005 version of the Dietary Reference, most professional dietitians use, says that "The lower limit of dietary carbohydrate compatible with life apparently is zero, provided that adequate amounts of protein and fat are consumed."
If you prefer to watch another 54 minute video here Prof. Feinman is discussing the science with Sam Feltham, owner of Smash the Fat Fitness Centers (UK).
Prof. Feinman recommends
The Big Fat Surprise: Why Butter, Meat, and Cheese Belong in a Healthy Diet; by Nina Teicholz. Here is a review in the Wall Street Journal. I found it long and technical and very detailed. Excessively so for most people I guess.
