Kitchen Chemistry: What are Calories, and Why Do We Eat Them?

At one time or another, we’ve all looked at a food package to determine whether a food is “healthy” or not, according to the nutritional doctrines of the day.  Often, the first (and perhaps only) thing that someone looks at on such a label is how many calories a food product contains per serving.  But what are calories?  Are they good or bad for us?

A calorie is a scientific unit of energy

What food packages label as “calories” are actually “kilocalories”, or a unit that equals 1,000 calories.  In chemistry (and other sciences), a single calorie is the amount of energy it takes to heat one milliliter of water one degree Celsius.  Wait…huh?

Momentarily setting aside the discrepancy in naming conventions, let’s paint a mental picture of what this “calorie” actually does.

Think of a centimeter.  A centimeter is about 1/3 of an inch.  Now, think of a square that’s 1cm on each side.  That’s a square centimeter because each side is equal, and all four sides are 1cm long.  To get the area of a square, you multiply the length–1cm–by the width–1cm–and get…you guessed it: 1 square centimeter (a unit of area).  Now, think of that same square and make it three-dimensional.  It’s now 1cm wide, by 1cm long, by 1cm tall.  That’s a cubic centimeter or “1cc”.  1cc equals 1 milliliter (1ml).

So, let’s take that 1ml (1cc) cube and fill it up with pure water.  Next, we’ll put a tiny amount of fuel under it and light it on fire, then wait for the temperature of the water to go up by one degree Celsius.  The moment it has done so, we put out the fire.  How much of that heat energy just went into the water?  Exactly one calorie.  How do we know?  Because by definition, 1cal is how much heat energy it takes to raise the temperature of 1ml of water by exactly 1 degree Celsius.  See?  We’ve just used a single calorie to heat water.  How scientific!

As it so happens, 1cc [1ml] of water weighs exactly one gram.  Isn’t the metric system neat?

Alright, I see that you’re wanting to know how this has anything to do with food.  The neat thing about a unit of energy (a calorie, for example) is that it doesn’t just measure heat energy.  It also measures kinetic energy, positional energy, nuclear energy, and–what we care about, right now–chemical energy.  The amount of chemical energy that our bodies can extract from a morsel of food is what is being measured and written down on the food label.  More properly, this is chemical potential energy: energy that’s stored in chemical bonds that can be re-arranged to make heat, movement, and other fun stuff happen.

Why, then, does the label use kilocalories instead of calories as its unit of measurement?  Creatures with over 15 trillion cells in our bodies, each of which need energy to survive, we need a great deal of energy to keep living.  So, any meaningful measure of nutritional energy will have to be in the thousands.  1,000 calories (“small calories”) = 1 “large calorie” or kilocalorie, which means that we don’t have to put a whole bunch of zeroes at the end of every “calories per serving” number on a cereal box.  That saves space and is easier to read.

Why do we need chemical energy to live?  Because without it, our cells would be rendered immobile–unable to respirate, unable to repair themselves, unable to move oxygen and water around, etc.  When our cells stop moving, we’re dead.  The tricky thing is that we can’t just pump heat into our bodies and have our cells magically turn that into energy; our cells are combustion reactors, not very unlike the engine of a car.

Wait, what?

Yes, you read that right.  An automobile takes chemical energy from molecules called hydrocarbons and breaks the chemical bonds to release energy.  How does a car do that?  First, it takes a bit of energy to get the process started.  This is called activation energy.  The battery sends a jolt through the system (with the help of the starter, spark plugs, etc.) that lights vaporized gasoline on fire.  That little explosion makes the pistons move, which cause the wheels to spin, and also gives parts of the engine enough kinetic energy to fill the reaction chambers with gasoline and light it on fire.  This produces a chain reaction, because each little reaction makes another reaction happen (until you break the “chain” by cutting power to the ignition process–A.K.A. “turning it off”).

Our cells do basically the same thing.  We have a chain reaction already happening inside each and every one of our cells since the moment of conception.  Our mother’s womb feeds those cells chemical energy in the form of sugar and other things–all of which are hydrocarbons–and that lets our cells keep going while having enough energy left over to make more cells.  Eventually, we get big enough to survive on our own, and voila! we are born!  Every day, we put more food into our bodies because that food is made up of hydrocarbons that our body knows how to break down.  We have enzymes, symbiotic microbes, digestive juices, and other things that let our bodies disassemble a wide variety of chemicals and turn them into the stuff that our cells run off of.

In fact, the chain reaction that keeps us alive is part of the same chain reaction that started life on this planet!  Think about that for a moment.  If, at any point between the creation of the first primitive lifeform and when we were born, that chain reaction had completely stopped, our mothers would have passed away before giving birth to us.  Isn’t that remarkable?

If cars use gasoline for fuel, what do our cells use?

Short answer: a simple sugar called glucose.  Most single-celled organisms love sugar because it’s the easiest thing to light on fire and get energy from.  In human cells, we have a little cell-within-a-cell called a mitochondria that does the hard work of lighting stuff on fire without making us explode and die.  Our cells take in glucose, burn it with oxygen, and use the energy that produces to turn a low-energy chemical (adenosine diphosphate) into a high-energy chemical (adenosine triphosphate), which then goes around and deals smaller, safer amounts of chemical energy to its “customers” in other parts of the cell.  That lets the cell move around and do its job for the rest of the body–whether that be passing around oxygen (red blood cells), killing invaders (white blood cells), contributing to larger movement (cells that are part of muscle tissue), storing energy for later (fat cells), and whatever else our bodies need to do.

The average adult requires 2,000 kilocalories of digestible chemical energy per day to avoid cell death

It’s true: if we don’t get enough calories, our cells die.  We need about 2,000,000 calories (2,000 kilocalories) per day to make sure that, at the end of the day, we still have the same number of cells that we started with.  Of course, if we spend a lot of energy on exercise, we need more than that to maintain the same number of cells; and if we don’t get much exercise, we’re spending less energy, and don’t need to eat as much chemical energy to keep us going.  If we want to lose weight, that means that we’re actively trying to make some of our excess cells die by not feeding them enough.  When cells are in distress, they release lots of chemicals that tell our brains (comprised of nerve cells) and other parts of our bodies that something is very wrong.  In other words, it hurts.  This can manifest in tiredness, moodiness, etc.  Our bodies are built to gather more energy and make more cells, not to lose energy and have cells die.

Up until the last 100 years or so, this wasn’t an issue because we didn’t have reliable food supplies, and therefore had very little capacity to overeat.  Food was too scarce, too expensive, and required us to spend a lot of energy to get it.  That kept us skinny.  Now, our food supplies are pretty awesome, and starvation is basically gone in the USA.  (Yes, it still happens, but almost never on the grand scale, which may be the most remarkable achievement in our species’ survivability, ever.)  We can now sit at a desk all day, spending almost none of our stores of chemical energy, and still have cupboards and refrigerators stocked full of food!  We eat because our bodies tell us it’s “time”, and if we get a little too much, our bodies say, “That’s great!  We won’t starve, now!”

Evolution is a little behind the times–and that’s why we get fat: our bodies are telling us to eat as much as we can so we don’t die of hunger, but we have so much food available that we can literally kill ourselves by eating too much.  From a biological standpoint, that’s a very good thing…mostly.

So, to finally answer the question in the title: we will die if we don’t get enough calories, and that’s why we eat them.  We read labels and diet because, for the first time in human history, literally billions of people have the unique problem of being so wealthy, in terms of food availability, that we can eat ourselves to death.  How many calories are too many?  That depends on your body’s size (how many cells you’re currently maintaining); the amount of chemical energy you’re spending on a daily basis (A.K.A. “exercise”); whether you want to gain weight, lose weight, or stay the same weight; and the unique quirks of your particular body’s metabolic process.  (Each person manages their chemical energy slightly differently, and as a result, some people can seem to “eat anything and stay slim”, while others can’t.)

Fun fact:The kinds of cells that die first are somewhat dependent on what you’re (not) eating.  Your brain and nerves love fat.  Your muscles love protein.  Everything loves carbohydrates (simple and complex sugars like glucose, fructose, sucrose, and starch–which is made of glucose and/or fructose).  Every diet has a trade-off.  Don’t believe anyone who tells you that a diet is risk-free.

The important thing to remember is this: (calories in) – (calories out) = (net gain or loss).  If the net gain or loss is 0, then you’ll stay the same weight.  More means you’ll gain weight, and less means you’ll lose weight.

Finally, please be aware that our bodies need things that aren’t caloric (don’t contain chemical energy that our bodies can burn) like minerals (iron, magnesium, etc.), vitamins, amino acids (what proteins are made of), and so on.  The only way you’re going to get everything you need is by consuming the right amount of calories (not too little or too much) from a wide variety of sources that also contain other stuff that you need.  If you eat nothing but starch, fat, and sugar, you’re going to get very sick, indeed.  Follow the age-old wisdom of eating a little bit of everything in moderation and not being too picky.


Current Organic Farming Methods: Why They’re Unethical and Unsustainable

Fair warning: this post will “burst your bubble” regarding the perceived virtues of organic food.

I’ve given this topic a lot of thought, lately.  I have a lot of friends who are really into the organic food movement, many of which often insist that it’s the only moral/ethical way to eat.  On the other hand, I also have access to persons who understand why not all farming is done organically.  The conclusion I’ve come to is that, in its current incarnation–notwithstanding future changes–the methods of farming, marketing, and distribution employed by the purveyors of organic food are grossly unethical for humanitarian reasons (i.e. hunger), and unconscionable in their reliance upon the ignorance of the public.  This is not to say that organic farming can’t become a wonderful thing, and ultimately replace more mainstream methods; but for now, I submit my thesis that it’s nothing more than a “feel good” hobby for those with disposable income.

Organic ≠ Sustainable

Most people who are into organic food have something to say for it, in terms of “sustainability.”  Let’s take a look at that word.


1:  capable of being sustained
2 a :  of, relating to, or being a method of harvesting or using a resource so that the resource is not depleted or permanently damaged <sustainable techniques> <sustainable agriculture>

 b :  of or relating to a lifestyle involving the use of sustainable methods <sustainable society>

If by “capable of being sustained,” we assume that we want to continue to be able to support the current population (and unavoidable population growth) with a given method, for an extended period of time, we must admit that “sustainable” also means sustaining humanity–not just nature.  So, if a method cannot sustain humanity at its current level, with expected population increases, then it’s not “sustainable.”

Ending World Hunger

Let’s take a look at why we use pesticides, in the first place.  Circa the late 1800s, we set out to find a way to feed everyone reliably, at minimal cost, so that everyone could afford adequate food.  In well-developed countries, we’ve very nearly accomplished this goal.  Doing so, however, required us to find ways of farming very efficiently and reliably, and chief among farming efficiency concerns is crop yield per acre.

Pests: weeds, insects, animals, fungi, and others are the single largest threat to crop yields.  If you don’t get rid of the pests, you won’t get much food.  In fact, you can lose entire crops due to pests, causing famine.  This is where pesticides come in: once about 30% of the plants in a field are affected by a particular pest (or broad type of pest), common practice is to apply whatever type of pesticide will remove (kill or otherwise hinder) the pests.  This more-or-less minimizes the use of pesticides (and the costs associated therewith), and ensures that the entire field won’t become affected, destroying the yield.  Most organic farms use pesticides to limit the effects of insects and fungi on yield–but do very little in the way of anti-weed care.  In fact, many large organic farms don’t do anything at all to remove their weeds; they just let the fields sit, and hope that there’s something to harvest when the time comes.

Organic yields are between 5% and 35% lower, on average, than mainstream methods.  The loss is dependent on what’s being grown: some plants don’t need a whole lot of non-organic care to thrive, but others–like grains (the staples of diets around the world!) take the biggest hit.  Of course, during bad years, pests can get out of control and take even more away from the crop.  When left untreated during an especially bad year, it’s possible that nothing, at all will be harvested.

Some organic farms get around this by using good, old-fashioned manual labor to get rid of weeds.  Like most eaters of organic food, I’m strongly favor of this–so long as I’m not the one doing it.  Usually, large farms make heavy use of migrant farm workers, who work 12-hour days, don’t get overtime pay, and typically only make minimum wage.  This might sound almost-reasonable…but if you ever spent a day pulling weeds in 90-115F weather, you’ll quickly change your mind.  (I can attest to this, personally.)  So, again, we see that this organic movement isn’t really a movement, so much as a market for those with enough money to pay someone else to do the hard work.

So, if we don’t want to do the work, ourselves, and find it unconscionable to have others do such hard labor for such long hours and little pay, where does that leave us?  For the most of the world, the answer is “starving.”  Even with this current labor force in place, 1 in every 100 people (according to the farm advisor I spoke to)–throughout the entire world, including “suburbia,” would have to quit their jobs and become farm workers–working 12-hour days for crappy wages in order for everyone to be able to eat organic-only diets.  Or, to ensure decent quality of life for the workers, 1 out of every 50 people would have to do the same.  Of course, the wages would still be terrible, but the work days would be closer to what we’re used to.  So, how about it?  Are you willing to quit your job and get to work?  For most of my readers, the answer is a resounding “no.”  This might induce some people to feel a wee bit hypocritical…which is exactly the point I’m making with this part of the essay.

This means that we’re back to the problem of inhumane treatment of those in the lowest rung of society, and non-organic food for the rest of us, until those with disposable income decide to get their hands dirty.

Dishonest Marketing

You may be surprised to know that many commonly used–and sometimes dangerous–pesticides are derived from nature.  One example of this is the insecticide Pyrethrin, which comes from Chrysanthemums.  This nerve agent is one of many pesticides permitted for use in organic growing.  It’s considered one of the safest insecticides out there, since it (supposedly) biodegrades quickly.  Nevertheless, users are warned:

Care should be taken to observe direction labels when using this substance around humans and animals. Overdose and toxicity can result in a variety of symptoms, especially in pets, including drooling, lethargy, muscle tremors, vomiting, seizures and death.[12] Toxicity symptoms in humans include asthmatic breathing, sneezing, nasal stuffiness, headache, nausea, incoordination, tremors, convulsions, facial flushing and swelling, and burning and itching sensation.[13] The latest information regarding toxicity of piperonyl butoxide has determined that it can pose a distinct health risk when it becomes airborne and pregnant women are exposed during the third trimester. This leads to delayed mental development in young children.

Others include the bacterium, Bacillus Thuringiensis, which produces deadly BT toxin, and causes the innards of insects to rupture–but is sort-of safe for human use.  Organic farmers use the microbe, directly (spraying it on crops), which is eaten by pests, causing it to release BT toxin.  Non-organic farmers use the BT toxin, directly.  It’s assumed to break down equally well in both cases, before it reaches your dinner table…but you may want to wash those organic veggies, anyway, since they’re probably still covered in Bacillus Thuringiensis.  Monsanto recently began to sell genetically-modified corn seeds, wherein the plants’ cells produce BT toxin.  This is somewhat different from spraying it topically, but in either case, you’re probably still going to be eating it.

So, let’s see a (metaphorical) show of hands: how many of my readers knew that “organic” food is sprayed with “chemicals?”  (Technically a “chemical” is anything made of atoms…but the term is used to mean “pesticides” when speaking of organic food.  Similarly, “organic” technically means “containing carbon atoms,” or “relating to life,” but is used differently when referring to food products.)  Do they put this on the label of the $8/pound grains, fruits, and vegetables you’ve been buying?  Of course not–because if they did, they could no longer get away with charging such a premium price.

So, what is “organic food,” really?  Marketing.

The essence of the perfect marketing campaign is to imply everything, but state nothing.  Yes, it’s grown differently–but not in the way people think.  Words are simply redefined, and standards formulated to let people think what they want to about the “product.”  “Natural” doesn’t mean safe–not by any stretch of the imagination!–but it does imply safety.  “Sustainable” sounds like it means that we can grow food this way indefinitely, without negative consequences–but it actually means dumping harmful stuff onto crops and into the ground–but only certain harmful stuff–and relying on the modern equivalent of slave labor to pull weeds, in the rare occasions that they bother to do so.  Additionally, “organic” implies GMO-free–but these farms aren’t regularly tested for cross-pollination, and the farmers have very good reason to avoid testing at all costs.

Price Gouging

The sad truth about the inefficiency of organic farming is that they have financial incentive to keep it inefficient.  The price of any good or service is subject to the Law of Supply and Demand.  If supply increases without demand increasing, price goes down.  When that happens, each hour of work or unit of currency you’ve spent on producing the product will bring back less than it otherwise would have.  So, if you want to maximize profits while minimizing expenses, you have to keep your product scarce.  This means that when you buy organic food in the store, there are several reasons why it costs so much:

1) Marketing: people will pay more because they believe in the product.
2) There’s more demand for it than there is supply.

In fact, most large organic farms produce mostly non-organic crops, and use their organic crops as a sort of “side gig” for bringing in a few extra dollars with a bare minimum of investment.  I’d be very surprised if the major organic producers in Butte County, CA produce even a tenth of the organic food that they produce in non-organic food.  The major farms with which I’m familiar (i.e. the ones with lots of acreage–not the tiny, local communes) produce most of the area’s organic food, but produce about 100 times that much via mainstream methods.

Conclusion: It’s No More Ethical Than Mainstream Food

In terms of plant products, organic food is no more ethical than non-organic food.  In fact, I believe I’ve made a strong case for it being markedly unethical, as presently constituted.  Despite this, I trust that in time, we’ll see a shift toward better organic practices, and much wider adoption.  Until then, though, I’m going to buy whatever’s cheapest, unless the more expensive food (1) tastes/feels substantially better, and (2) is still within my price range.  I won’t support a trend that doesn’t work as advertised.

You may have noticed that this post didn’t cover animal products.  This is a very different matter in some ways, but in others it’s much the same.  Issues of hunger, dishonesty, pesticides (by any other name), and so on still come up…but free-range animals are definitely a lot happier than caged or “cage-free” ones.  (Note: “cage free” animals are crammed in butt-to-nose, wade through their own feces all day, and live in warehouses where their dead siblings sometimes rot on the floor.  I question whether this is at all ethical.)

Let’s produce an organic movement that’s worth having by removing our rosy glasses and seeing the ugliness of what we have now.  Only through seeing how things really are can we hope to change them for the better.

For further reading on how “organic” foods might kill you, go here.