After the last blog post on calorie magic, my husband–whose intellectual response to people challenging me on the internet is to want to give them a virtual wedgie–asked me why I didn’t just engage those cute little white dude-o-scientists who are so pumped about how IT JUST MUST BE CALORIES CALORIES CALORIES CALORIES in some sort of PubMed duel to the finish.
My explanation: I don’t do PubMed duels. PubMed is a wonderful thing, and the internet has given us tremendous access to a great deal of information, much of which is used to confirm our own preconceived notions, even if (especially if?) we don’t fully understand what those notions actually are. As I’ve said before, a pastiche of PubMed citations frequently boils to a bunch of snapshots taken out of context of the larger literature–and out of context of a full understanding of physiological and biochemical realities, not to mention social and cultural ones–that may or may not express a physiologically significant or practically useful concept.
And this is problem: I’m not convinced that calories express a physiologically significant or practically useful concept. Here’s what I figure. If calories were so FREAKIN important, then my biochemistry books should be rife with information about them. But that does not seem to be the case.
[I took my first biochem class at age 45, weeping my way through one excruciatingly difficult exam after another. I emerged–bloodied by unbowed–to joyfully sign up for 3 more semesters. I don’t consider myself an expert by any stretch; I just feel that biochemistry is sort of the key to the universe, certainly the universe of nutrition. If something doesn’t make sense from a biochemical perspective–which would apply to about 90% of the Dietary Guidelines–it shouldn’t be part of nutrition policy.]
I did this a while back, just for my own peace of mind, and I don’t know how useful it will be to any of you, but here’s what my collection of biochem books has to say about calories. Spoiler alert: Not much. [So you can stop here if you have a life.]
My biochemistry books, in order of how much I love them, least to most:
James Groff & Sareen Gropper
I don’t know why I have this book.
–“Calorie” is indexed to a passage on units of energy in a discussion of thermodynamics. Calories are not mentioned again.
–“Calorimetry, direct” and “calorimetry, indirect” are indexed to passages discussing the measurements of energy expenditure. It contains this notable summary:
” Although changes in energy balance produce weight changes, the extent of these changes varies from person to person.”
Eric Newsholme & Tony Leech
I got this book with great anticipation, as it seemed to promise a better integration of biochemistry and physiology than most biochem texts. But like some sort of weird Asian-fusion spicy wonton Alfredo dish, I guess it is just trying to do too much. There is not enough detail here for me, and the reader is left to sort of assume “magic elves in a box” in too many places, which–as far as I am concerned–defeats the whole point of learning biochemistry.
–“Calorie” is not indexed.
–“Calorimetry” is indexed. This couple of pages highlights the limitations of measuring calorie expenditure in the human body.
Pamela Champe, Richard Harvey, & Denise Farrier
This is the boy-toy of my biochem texts. I don’t love this book, but it is much more portable than my other biochem texts, so I can take it out in public without too much embarrassment.
–“Calorie” is not indexed.
–“Caloric consumption,” “caloric restriction, weight reduction and,” and “calorimeter” are indexed.
“Caloric consumption” addresses the fact that the source of the increase in calories consumed by Americans since 1971 is carbohydrates.
“Caloric restriction, weight reduction and” is indexed to a page includes the following helpful information:
“Caloric restriction is ineffective over the long term for many individuals.”
Donald Voet & Judith Voet
I approach the Voets with the reverence and respect due a giant doorstop of a book like this. Like that scary old professor who knows everything, it is intimidating, but, well, it knows everything.
“Calorie (cal)” and “Calorie, large (Cal)” are indexed to the same place. The indexing refers to a table that compares thermodynamic units and constants as an adjunct to a passage on the First Law of Thermodynamics. This passage contains a little nugget of joy for those of us who insist that conversations about weight management may need to consider more than just how many calories go “in” and how many calories go “out.” Unless you are a fully registered and certified geek, you may want to just skip ahead:
“Neither heat [i.e. what is measured by calories] nor work is separately a state function [i.e. quantities that depend only on the state of the system] because each is dependent on the path followed by a system in changing from one state to another . . . If [the First Law of Thermodynamics] is to be obeyed, heat must also be path dependent. It is therefore meaningless to refer to the heat or work content of a system (in the same way that it is meaningless to refer to the number of one dollar bills and ten dollar bills in a bank account containing $85.00).”
This is why when someone talks about a person storing “800 calories of energy as fat,” I hear something that makes about as much sense to me as saying a person can store “$85 dollars worth of money in his bank account as four twenties and a fiver.”
Calories are otherwise never mentioned again in the rest of the 1,310 pages of this book.
Mary Campbell & Shawn Farrell
Campbell y Farrell is my warm fuzzy teddy-bear of a biochem book. I LUV it. Cuddle up with C&F for a well-written, easy-to-understand (as these things go) romp through the wonders of biochem.
–“Calorie” is not indexed.
–“Caloric restriction” is indexed to a discussion of longevity and sirtuins, not weight loss or obesity.
David L. Nelson & Michael M. Cox
This is my favorite biochemistry book ever. If it were available and I were single, I would marry it in a hot second.
–“Calorie” is not indexed. Nor is “kilocalorie.” Nor anything else that I could think of having to do with “calories.”
There you have it. Seems to me that all those broscientists want to talk about is something that doesn’t have a lot to do with the keys to the universe of nutrition. I don’t mind talking biochemistry, but the basic biochemistry that I’m familiar with has virtually nothing to say about calories.
And if biochemistry isn’t too concerned with calories, why should you be?