Chinese Food and Psychological Epidemiology

Epidemiology is the study of how diseases are propagated through a population.  It’s funny because fear operates on a similar principle — it’s more contagious and less dangerous, but fear spreads through a population with ease.  The worst part is that while contagious diseases typically come from a virus or bacterium, fear is manufactured out of thin air and spreads its fight-or-flight response unhindered and instantaneously to whomever is close enough to experience it.

We’ll talk about food in this discussion, and attempt to explain how the epidemiology of fear affects our social perceptions of what is “healthy” or “bad for you.”  Even if you’re not a chemist at heart, we’ll break it down in an easily digested (see what I did there?) format.  Our ultimate goal is for you to understand how and why misconceptions arise, so we won’t waste your time with esoteric chemistry lingo.

Let’s consider an ingredient in food that is widely feared, but to prevent bias we won’t give it a name just yet.  Look at its chemical structure below, keeping in mind that long horizontal zig-zagging chain is just a bunch of carbon atoms linked together:

On the right side, you see “Na,” which is the chemical symbol for sodium.  If you slapped a chloride onto that sodium, you’ve have table salt. Notice how it has a + sign above it, meaning that it’s slightly positively charged.  Of course, a positively charged thing is attracted to a negatively charged thing.  As it turns out, the sodium can bind to the oxygen (it has a minus symbol next to it), because opposites attract.  But here’s an important note: this doesn’t mean these two parts are now permanently linked.  The sodium and oxygen atoms here are only electrically bonded to each other, rather than a stronger type of bond (such as the ones that connect the rest of the atoms in this entire molecule.  Their bond is weak and it’s broken easily.

Normally, the Na+ above is replaced with a hydrogen, and you’ll have -O H on the end there instead of -O Na. In your body, this large molecule naturally exists as the picture above.  In other words, that oxygen with a negative symbol floats around in your body, and it’s able to pick up any positively charged thing it encounters.  That could be hydrogen in water or, as above, a sodium atom.

You can imagine that this molecule floats around and just happens to bump into a sodium atom, at which point the two join together, at least temporarily, in electric attraction.  They’ll probably separate in a fraction of a second, but they can bond for a short period.

What’s the big reveal here?  Well, the molecule above is one of the twenty amino acids that make up every protein on earth.  Beef, eggs, cheese, seafood, chicken, and the rest all incorporate this molecule to a huge extent.  You’re getting trillions and trillions, if not more, of these molecules at every meal.  In fact, for the math-oriented reader, we’ll break it down below.  If you’re not a huge fan of numbers, skip this optional section.

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Amount of the above amino acid in an average 3 ounce hamburger:

• The average hamburger has 24.8 grams of protein, of which 3.751 grams is our mystery molecule above.  A mole of this molecule weighs 147 grams, meaning we have 0.025 moles per serving, or 2.5% of a mole.
• 2.5% of a mole is equal to one and a half septillion molecules.  It’s exactly 1,536,123,809,523,809,523,809,523 molecules.  The take-home message: An average hamburger has one and a half million trillion copies of this molecule.  It’s unfathomably large.

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So you’re getting this amino acid at every meal in unbelievably high amounts.  If you’ve salted your burger, you’re also eating lots of sodium atoms, and there’s a good chance these two would come into contact naturally and bond with each other temporarily.

With that out of the way, let’s reveal our molecule: we’re talking about monosodium glutamate, or MSG.  Now, before your mind jumps to anything you’ve previously been told about MSG, stick with me here and review what we’ve just discussed.  Your body probably contains millions of millions of millions of monosodium glutamate right now, simply because you had protein with salt in a recent meal.  So what’s the controversy?

MSG has been accused of causing many health problems, to the point where Asian restaurants proudly proclaim they don’t use it as an ingredient in their food.  Whether they actually believe it’s harmful or not is irrelevant because their society believes it to be harmful.  It actually stems from an anecdotal report in a 1968 issue of The New England Journal of Medicine. Here’s what the person said:

I have experienced a strange syndrome whenever I have eaten out in a Chinese restaurant, especially one that served northern Chinese food. The syndrome, which usually begins 15 to 20 minutes after I have eaten the first dish, lasts for about two hours, without hangover effect. The most prominent symptoms are numbness at the back of the neck, gradually radiating to both arms and the back, general weakness and palpitations…

Imagine reading this in a scientific journal or magazine.  It might spook you and make you want to avoid whatever ingredient is causing such a reaction.  You might look at Chinese food ingredients, notice that MSG is in nearly all of them, and righteously declare a war on MSG.  Does this make sense?  Maybe, if it’s the only common link between every dish.

What else could explain this man’s symptoms?  Maybe he ate too much, or too quickly.  Maybe he ate something fried in an oil that triggers an allergic reaction.  Maybe he’s allergic to seafood and the pork-fried rice was contaminated.  Whatever the reason, there are infinitely many “possible explanations,” and the cause warrants a bit of digging.

Consider the effects of a high-sugar meal on your body.  You’ll pump out a ton of insulin to clear out your blood of excess sugar.  If it clears out too much, you might end up with low blood sugar, the opposite end of the spectrum.  What does low blood sugar feel like?  If you’ve gone 14 or 15 hours without a meal, you probably know its symptoms: for many people, weakness or aches are both common symptoms.  You might argue that this man’s reaction was not due to any particular ingredient found in Chinese food, but rather, by the massive flood of simple sugars he fed his body when he ate the rice he was served with his meal.  If you’ll recall our recent discussion on the genetic variety in tolerance for rice, you’ll remember that in general, western nations don’t digest rice as easily and efficiently as those that have been eating it as a staple food at every meal for thousands of years.  Perhaps there is less digestion in the mouth, which leads to large digestion in the small intestine and stomach, which could theoretically lead to a larger spike in blood glucose.  From here, you might start to wonder if perhaps the rice is a viable candidate, rather than the MSG.  Of course, none of what I’ve written in this paragraph has been scientifically confirmed by a double-blind, peer-reviewed study, so take it with a grain of salt; it’s just my conjecture. The point I’m trying to make here is that without scientific evidence, neither the rice nor the MSG can be conclusively linked to the anecdotal symptoms of one man in 1968.

We haven’t concluded that MSG is not harmful in the above paragraph.  We’ve only concluded that it cannot be singularly pin-pointed based on current scientific consensus.  In fact, that opposite is true: here are three double-blind  or placebo-controlled studies debunking the harmful effects of MSG.  If double-blind studies can’t determine potential harmful effects, it seems reasonable that one man writing anecdotally should not be taken as the voice of molecular reason and propagated as fact for decades.

So where does this leave us with MSG?  There’s not been any evidence that it is responsible for the symptoms it’s accused of, and we have already established that this molecule is already present in your body in a number bigger than you can type into a calculator.  We can’t say with accuracy how much MSG might be added to any given food dish, but even if it exceeds the amount of glutamate naturally occurring in the meal, it exists in exactly the same form in your body and will be treated exactly the same.

So what about overdosing on glutamate?  Can glutamate all on its own cause these symptoms?  Glutamate is itself a neurotransmitter, meaning that it’s what your brain uses to transmit signals to the rest of your body.  Too much of any neurotransmitter can be damaging by what’s called excitotoxicity.  The LD50 for MSG in rats is 16.6 grams per kilogram.  If the average rat weighs 0.2 kilograms, it would need to eat 33 grams, or over an ounce of the stuff all at once to have a 50% chance of death.  Let’s go out on a limb and say that the LD50 scales more or less with humans.  In fact, let’s say that our tolerance is lower and that we can only take 12 grams of the stuff per kilogram before we die.  If a 160 pound person weighs 72.5 kilograms, he or she would have to eat 870 grams of MSG all at once to die half of the time.  How much is 870 grams?  It’s nearing two full pounds.  Look below for the final, optional math on this issue:

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• If 870 grams of MSG is our theoretical LD50 for MSG in humans, and it has a density of 1.62 grams per cubic centimeter, we would have to ingest 537.03 cubic centimeters, or just over half of a cubic meter.

 

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 Here’s what a full cubic meter looks like.  If you think you can eat half of the volume of this box in MSG powder, let alone anything at all, then you’re in grave danger of MSG overdose and excitotoxicity, but you’re going to have to work against your body to force it down your throat.  Of course, our LD50 for humans is one I just made up on the spot, because we know that LD50 numbers in rat shouldn’t scale directly to humans.  But making MSG even more toxic to humans than rats, as we did in the above example, still illustrates the point of just how much you’d have to take to cause problems.

 So what’s with the title of this discussion?  There’s no overt fear-mongering over this issue.  Instead, it begins with an anecdote, whose message is propagated across cities, states, and eventually countries to produce a general consensus that is not based on any scientific evidence.  It can happen with anything — food, rock and roll, or violent video games — but what a population believes to be true and whether it is actually true are often not the same.  Always question the source, and if you’re skeptical, do just a little bit of digging.  What you find may surprise you.

Hybrid Animals: Yes, It’s as Terrifying as it Sounds

Humans can’t mate with giraffes to make humaffes, for a variety of reasons.  For one thing, our DNA is just too different.  It’s like pouring oil over water — the parts are similar, but they don’t allow for mixing and merging.  For another reason, humans don’t live in the same geographic regions that giraffes tend to inhabit.

Maybe you’ve heard of the liger, a cross between tiger and lion.  Or perhaps you know that mules are really the child of a horse and donkey.  Mules are sterile, though, so they can’t ever produce offspring and branch off into a new species.  Think about that for a second, though: if mules were able to have children, they would eventually splinter off from their horse-donkey parents and represent a completely separate path on the evolutionary tree.  This is, in fact, precisely how many new species develop.  If mules are just as fit for their environment as either of their parents, then they have a good chance of sticking around.  Even better, if mules somehow combined the speed of horses and the stability of donkeys, perhaps they could reach a mountain plateau that neither of their parents were previously able to reach.  Here, a few mules might produce a few children, and the cycle would repeat, giving us a new species that lives in a different geographic area with different conditions (climate, plants to eat, or predators).

So hybrid animals aren’t new, but they are exciting, because there is a hybrid you should watch out for: the grizzly bear-polar bear hybrid, the grolar bear.  That’s this guy right here:

They’ve been reported in both captivity and in the wild.  In the wild, it’s unlikely that a polar and grizzly bear meet up because of where they live, but it could perhaps happen rarely.  Look at the chart to the right and you’ll see that there many possible combinations of parent species that would produce a grolar bear.  Terrifying, huh?

Grolar bears retain some characteristics of both of their parent species, which makes them look different from either parent alone.  They also tend to behave like polar bears rather than grizzlies, including predator and play behavior.

The truth is that grolar bears are so rare that we hardly know anything about them.  We’re not really sure if they’re physically viable as a separate species, if they’re able to have children, or if they’re somehow better adapted for the environment and thus more likely to survive.  If they were more fit, we might expect both grizzlies and polar bears to die out over time while grolars replace them as the dominant species.  But given the geographic differences between the two species, the grolar would have to take over a lot of land spanning a huge variation in climate.  This is pretty unlikely (as in, not going to happen).  In the meantime, grolars will be born, albeit rarely, and both polar bears and grizzlies have nothing to worry about because they’re not being threatened by a new species that’s more fit than they are.

There’s a lot more to say about hybrid animals including how they form, how they differentiate and branch off from existing species to fill a ecological niche, and endless topics concerning the genetic mechanisms of hybridization.  Hopefully our discussion here taught you something new or interesting!

I’ll Take the Pork Fried Rice, Please!

Digestion is a huge topic, as we learned in the last discussion.  This time, let’s zoom in on a quick little fascinating molecule that controls a lot about the way our food is digested.  We’ll start by looking at an enzyme called salivary amylase, and see if we can apply it to some larger principles about humans around the world.

Amylase in a nutshell, retrieved from http://muirbiology.wordpress.com/national-45/unit-1-cell-biology/6-proteins-and-enzymes/

Salivary amylase is an enzyme, meaning that it’s a small proteins whose function is to make it easier for reactions in the body to take place.  To give you a better idea of what it does, it’s present in your saliva when you’re eating, so that whatever you’re putting into your mouth begins to break down right away so you can absorb it more easily.  Without salivary amylase, your food wouldn’t be broken down as easily, and you’d have to work harder to digest and metabolize.  The word “amylase” in the enzyme’s name refers specifically to the breakdown of starches — potatoes, pasta, pizza, toast — meaning that this particular enzyme only breaks down carbohydrates, and it does so the second food enters your mouth

Yeast feed on glucose, and the result is alcohol – the kind we drink in beer and liquor!

 

If you know any home beer-brewers, then you might be interested to hear that this is a common treatment for the yeast in the beer.  The yeast normally feed on glucose, the smallest unit of sugar.  If we add long chains of starches, we can also add amylase to cut up those chains into maltose (similar to glucose) molecules that the yeast can eat.  If you want to make a loaf of bread from scratch, the flour you add will serve better as yeast food by first breaking it down by amylase.

So now we know what this enzyme does: it breaks down carbohydrates into simple sugars at the first level of digestion — eating!  What’s really interesting here, though, is that across the planet, different populations of humans (and other animals!) have evolved to use this enzyme better than others.  For example, a human’s DNA contains way more copies of this enzyme.  In other words, any time a cell makes proteins, it makes more copies of this amylase enzyme.  Think of it as writing on a computer: if you type the letter “a” one time, you’ll only get one letter on the screen.  Hold down the key, though, and you’ll generate 15 or 20 copies of the letter.  Our DNA does the same thing, with the end result being that for the same stretch of genes, our bodies produce more copies of the enzyme, instead of just one or a few.

Humans are complex eaters: we’ve been eating starches, fat, and proteins forever and ever, and our bodies have had to come up with different ways to digest all of these components.  In a 2010 issue of American Scientist, the following is written:

The salivary amylase levels found in the human lineage are six to eight times higher in humans than in chimpanzees, which are mostly fruit eaters and ingest little starch relative to humans.

So chimpanzees don’t eat a lot of starch.  Therefore, they don’t need a lot of amylase to digest food.  Now let’s take a look at the other end of the spectrum.  If you’re from the USA or Canada, you probably don’t eat rice all that much.  Of course, you probably know that in Asian countries like Korea, China, and Japan, rice is eaten at nearly every meal and is the staple food of those cultures.  Who would you think would have a higher level (more copies) of salivary amylase, someone from the US or someone from Japan?  Before you answer, look at the nutrition chart to the right: white rice is primarily carbohydrate, which as we know, is converted to simple sugars through digestion (and salivary amylase when it hits your tongue!!)

Hopefully you’re having the following train of thought right now: Asian populations eat rice more frequently, so if they have more copies of salivary amylase, they’re better suited to eating and digesting rice on a regular basis.  Indeed, this is the case.

For example, a Japanese individual had 14 copies of the amylase gene (one allele with 10 copies, and a second allele with four copies)… In contrast, a Biaka individual carried six copies (three copies on each allele). The Biaka are rainforest hunter-gatherers who have traditionally consumed a low-starch diet.

Perry, GH, et al. Diet and evolution of human amylase gene copy number variation, Nature Genetics 39:1256-1260 (2007).

The bolding is for emphasis and done by me to show you the huge difference between cultures.  A Japanese individual has waaaay more copies of this gene, and thus way more copies of the protein, in their saliva and bodies.  The more copies, the easier it is to eat rice and put it to metabolic use.   See the chart below for more details:

This chart was obtained from another awesome science blog, available here: Confusedious

This brings us to another idea: if you are or have friends of Asian descent, it’s quite likely that even if you live in the USA, your genes carry more copies of the amylase gene and you have an easier time digesting rice and other starches.  Someone with genes from a low-starch culture would carry less, and would be able to tolerate fewer starches before his or her body began to show signs of metabolic dysfunction (however slight and mild they may be).

So we’ve seen here that a single gene for starch breakdown has a huge impact on how we digest food, and that the gene itself is abundant in places where it’s been historically advantageous.  In regions where it’s not so important, modern populations will carry fewer copies of the gene because their ancestors ate less starch.  It just goes to show you that even though we’re all living in a connected world, our genes are still responsible for our individual responses to the food we eat.  No two individuals are the same when it comes to food metabolism because we’re all an amalgam of our forebears tracing back a lineage of hundreds of thousands of years.

Glycogen: The bucket’s half-full

Many scientists might claim that the human body is largely uncharted territory.  We know so much about how we function, but what we know is a drop in the bucket compared to what is not yet discovered.  A body is not as large as the unexplored universe, nor deeper than the deepest parts of the ocean – it’s right here in front of us, and we still can’t figure it out.

Needless to say, some of the more recent discoveries about our biochemistry are still not quite common knowledge — nutrition junkies and doctors could tell you a lot about yourself that you’d be surprised to hear.  Even though we could pick one of millions of topics to discuss concerning the workings of human metabolism, today we’ll focus in on a pretty simple cause-and-effect relationship about food.

Let’s start simple: is a slice of pizza different than a steak?  Obviously, they’re different foods, but how about nutritionally?  Do the calories in pizza and steak get treated the exact same way once they pass through your lips and into your stomach?  The short answer is no; the long answer is “not even a little, and here’s why:”

Everything we have ever eaten as a species comes in a mixture of three basic components: fats, proteins, and carbohydrates.  You know these by sight — butter is pure fat, a lean steak is pure protein, and spaghetti or toast are both pure carbohydrate.  Each of these foods provides energy to you in a different way, because your body has to break down them down into their constituent molecules.  A steak is made of long chains of amino acids, and a fully digested steak is nothing more than that same chain cleaved at every link in the chain.  A piece of bread starts out as long chains of sugars, but when it hits your bloodstream, as all the food we eat does, it does so as individual molecules of glucose, or fructose, or whatever kind of carbohydrate it’s made from.

Let’s focus in now on the carbohydrates: they’re made of little more than carbon, hydrogen, and oxygen — in fact, by definition these are their only constituents.  We now know that every carbohydrate you eat is broken down into individual pieces, called monomers, when it gets digested.  If you eat a potato, a slice of toast, or a bowl of spaghetti, the end result is nearly identical – the amount of free glucose in your body rises.  Take a look at the chart below which shows when and where in the body each type of food molecule gets digested – notice how they all have their own mechanisms of being incorporated into your body.

So we can see that the three types of food molecules — fats, proteins, and carbohydrates — are digested very differently from each other.  On the other hand, if you consider only the carbohydrates, each of the many kinds of carbohydrates are digested in essentially the same way.

Carbohydrates are great because they’re reassembled as something called glycogen, which is short-term storage for your body.  If you’ve ever had to lift up a heavy box (put your back into it, lift with your knees, etc., thanks for the advice Mom!), spring across the parking lot in pouring rain, or do 10 push-ups in ten seconds, then you’ve used glycogen.  It’s the only kind of food molecule we can put to work instantly because it gets stored in our muscles, which use it to fuel our burst-type motions.  It’s also stored in the liver if our muscles get too full of it.  After all, we only have so much space in every cell for glycogen, and if we fill up our muscles, we’ll need a repository somewhere else.

Here we can see that ATP, which is the main energy “currency” of the body (meaning, all incoming energy sources eventually end up as ATP so they can be spent universally in the body, like having a credit card instead of Canadian dollars!) is made from many sources including gkycogen and fatty acids.  Notice how quickly glycogen is turned into ATP compared to fatty acids — over five times the speed! When you’re in a fight-or-flight situation, you want the fastest possible mode of energy generation, and glycogen is the go-to guy.

Herein is the downside to carbohydrates: while they provide instant, easily accessible energy, it doesn’t last long.  A few minutes of sprinting can wipe out your glycogen.  But if you were a caveman running from an enemy tribe who had recently discovered how to use a bow and arrow, you can bet you’d be thankful for the burst energy carbohydrates can give you.

Let’s look at it from a slightly different angle — all carbohydrates are broken down into sugars.  We already said carbohydrates break up into glucose or fructose, or whatever monomer it might be, but all of those monomers are sugars.  If you were to go to the cabinet in your kitchen and weigh out an ounce of sugar and an ounce of spaghetti, you might be surprised to learn that your body treats them both identically when it comes to getting energy out of them.  A slice of bread? A tablespoon of sugar is roughly 12 grams of carbohydrates – think of it as 12 grams of sugar.  The average bread slice has 36 grams of carbohydrates – think of it as 36 grams of sugar.  They look and taste different, but because they’re both sugars, they’re both digested and used the same way by your body.

 

We just mentioned that you store glycogen (remember, that’s the storage form of these sugars), but you can only hold so much.  Picture a big bucket with a tiny hole in the bottom — if you use your garden hose to fill the bucket half-way full, it will slowly drain out over time, and in a few hours or days the bucket will be empty.  On the other hand, if you fill it up to capacity and then continue to spray water over it, the water will overflow from the top.  Our glycogen stores work the same way — we can only hold so much, and we slowly burn it over the course of a day to fuel our brain and our motion.  In the chart to the right we can see that we store 840 total kilocalories as glycogen at any given time.  Dividing this by 4 tells us the number of grams of glycogen that is our maximum – it’s about 210 grams, and we have to add an additional 4 times this amount to account for the water weight associated with storing glycogen.  This is roughly 1000 grams, or 2 pounds of quick energy!!  Our glycogen bucket holds almost nothing compared to our fat stores, which, in this chart, account for about 66 pounds!  Compare that to the 2 pounds for glycogen; fat is by far the most abundant energy source we have, and it’s a shame we can’t utilize it more efficiently.

As for glycogen, we can refill the energy bucket by eating ice cream, bread, or pasta.  But say you go to town one night and have 5 bowls of pasta for dinner — you’ve given your body more glycogen than it can store in your muscles and liver.  What happens then?

Remember how we said above that the food you eat gets transported around in your bloodstream?  All the carbohydrates (they’re now individual sugar molecules) are circulating around your blood, knocking on every door to see if there’s extra room in the club for one more partygoer.  If every muscle and liver cell is already jam-packed, these sugar cells have no choice but to continue the circuit around your body.  But there’s a catch here – high blood sugar is toxic and can easily kill you.  Your blood needs very specific conditions to function well.  But give it a true emergency like an excess of sugar, and it has to do something drastic, or you’re going to have some serious health issues, like being killed to death.

Thankfully, our bodies are smart.  Any extra sugar is swept up by a hormone called insulin –– you’ve probably heard of it in relation to diabetics, and yes, that’s related to this — and insulin does a great job of moving sugar from your bloodstream into cells by changing it into something else.  It’s a process called de novo lipogenesis, and it converts sugar into fat.  If you fill up your glycogen bucket and it begins to overflow, your body has no choice but to pack it into your cells as body fat.  The reason for this is pretty simple: fat cells have pretty much unlimited storage, while we already said that glycogen is very limited in its capacity.  If you go without a meal for 12 hours or so, you can be pretty certain you have very little glycogen left to use.  On the other hand, fat cells can expand almost indefinitely, so any extra energy is going to go to them and packed away for a rainy day.

What’s the moral here? If you overfill your glycogen stores, any excess is converted to body fat in de novo lipogenesis.

What about protein and fat?  Proteins are broken down into amino acids, which are then shuttled around your bloodstream and used in your cells to make up pretty much everything you can see when you look at someone — skin, hair, eyes, muscles, and more.  Say you go out for dinner tomorrow and eat 12 sirloin steaks.  You’ve given your kidneys a workout, and you’ve given your body more protein than it currently needs.  Luckily, we can convert those amino acids into glucose, which can then be stored as glycogen.  Do you see a potential problem here?

If your glycogen stores are already full, and you overdose on protein, the extra protein is first converted to glucose.  Your cells respond with a hearty “we don’t need no glucose!” and then insulin is forced to do its job to prevent your high blood sugar from putting you into a coma.  So now we know that an excess of carbohydrate or an excess of protein can pretty much lead to the same result.

A similar story goes for fat, if, for example, your breakfast happens to be two sticks of butter.  You have a lot of long-term storage all at once, and chances are very good that you’ll pack it away as body fat until you really need it.

So if all three types of food molecules can potentially end up as fat, doesn’t that contradict the idea that they’re all digested differently?  Well, only if you’re considering excesses — too much of anything and your body has to deal with it accordingly.  You’ve only got so many kinds of energy storage in your body — glycogen, body fat, and even proteins can be metabolized if you haven’t had a meal in a few days.  The idea here is that you’ve got a bucket full of glycogen that you can fill and empty over time, but you’ll ideally never want it to overflow.  It can definitely go empty, and that’s not really problem — if you run out of glycogen, your body starts moving fat out of its 66 pounds of fat cells to use for energy instead, though there is a short transition period that can leave you feeling fatigued.

The concept of glycogen storage is one that many people may not be aware of, but it has everything to do with what we eat and more specifically, what kinds of the three types of food molecules we’re eating.  Someone on a bread and pasta diet will be constantly refilling and overflowing their glycogen stores, and the result is body fat accumulation to prevent toxic levels of blood sugar.  Next time you have a meal, try to guess what types of food molecules you’re ingesting — a mixture of proteins and fats, perhaps?  Carbohydrates and proteins? The ideal meal is one that gives you all three types of food molecules, and not too much of any one of them.  One hundred calories of bread and one hundred calories of steak are treated very differently in your body because they’re made of up different molecules, and therefore have different functions in helping to keep you alive.

Think about your glycogen stores next time you have a meal, and try to imagine whether bucket is half-full or half-empty, whichever way you prefer to think of it.  We’re not as deep as the oceans or as large as the universe, but it’s processes like energy use that really make our jaws drop.  It’s the moment we realize how complex we really are.

Margarine, Crisco, and the “health” craze: Immature Science

It’s a very human thing to discover an exciting new prospect and want to share it as soon as possible so that we can all reap the rewards.  This happens a lot in science as well: when thalidomide was put on the market decades ago, we wanted pregnant women to stop having morning sickness.  Instead, the lack of research and long-term effects meant that birth defects were uncommonly high among those taking the drug.  Had we taken a little more care with manufacturing or research, it may not have happened that way.  The world got excited, and many newborn children paid the price of the immaturity of the compound’s data.

It’s an ethical question: when do we have “enough” research to peg a new compound as safe to use?  If we find a new way to preserve food that seems reasonably safe, should we bother to test it long-term before putting it out on the market?  This is the exact issue that occurred when butter substitutes like margarine and Crisco hit the market.  Their properties are amazing to behold and the chemistry is an accomplishment of science.  Yet, if only we had tested them a bit longer before putting them on the market…

What they were going for…

And what they ended up with. Note the weird bond in the middle — it’s a trans-fat!

Alas, the heart of this matter is what we call “trans fats,” which nearly everyone has heard of at some point.  They were banned in some states, and the FDA requires you to list the amount of trans fats in your food products.  What makes them so “dangerous?” In short, they’re a fabrication of fats, and unfortunately for us, they’re not an exact replica.  The differences that trans fats bring in their molecular structure are responsible for the (justly so) backlash against them, and their eventual demonization.  40 years ago, scientistsand laypersons alike were in awe of the amazing substance called “partially hydrogenated oil.”  It’s time to delve into what that really means, and how it makes trans fats dangerous.

Quiz: at room temperature, is olive oil a liquid or a solid?  How about bacon grease?  The difference is that bacon grease is called a “saturated” fat, meaning that the long carbon chain that makes up the fat is filled to its limit with hydrogen atoms.  Each carbon in the chain can hold 2 hydrogens, as well as make 2 connections to other carbons.  These chains end up long and very straight, so that when a bunch of them come up next to each other, they pack tightly enough to solidify — this is why animal fats are solid at room temperature.  It’s simply because the fat molecules are better lego pieces with each other than other fats.

Those other fats, of course, are unsaturated fats.  They’re mostly vegetable or nut oils, like olive, sesame, almond, peanut, and soy.  They’re unsaturated because they’re not packing their carbons to the brim with hydrogens — and when a carbon doesn’t have enough hydrogens, it has to make a bond to a carbon it’s already attached to, which gives it a double bond with another carbon.  To provide some background, carbon must make 4 bonds when it can, otherwise, it’s extremely reactive.  It doesn’t care if it makes 4 separate bonds, or 2 double bonds — as long as it’s making 4 bonds in some way or another, it’s happy and stable.

We said these fats aren’t as good “lego” pieces as saturated fats are.  Why’s that?  Well, when carbons make a double bond to each other, their orientations change: instead of being perfectly straight, they tend to bend at angles and kink up here and there.  They take up a lot more space because their shape has been forced to change.  This means they won’t pack as tightly (five people standing in a phone booth with arms at their sides would pack in tightly, but two people with their arms out could not easily fit in this same space!), and so they don’t solidify.  Olive oil is still liquid at room temperature because it can’t pack tightly enough.

By a miracle of science, we figured out how to shoot up unsaturated fats with more hydrogens molecules.  In other words, we figured out how to transform olive oil into butter – it would be a solid at room temperature.  It’s great for preserving food since it won’t get all liquidy on you, and it’s the reason that Crisco stays solid even when left on the counter. It’s why you never have to stir your peanut butter in the jar unless you buy a jar with only a single ingredient on the label.  But we didn’t quite hit the mark when we employed this technology, and here’s where it gets a little scary.

It turns out we’re not perfect at shooting up those fats with hydrogens, and we miss the 100% mark some of the time, leaving those fats “partially hydrogenated,” which gives them a unique molecular structure and shape.  When that happens, we’ve created a type of fat that the human body has never before encountered in its many millions of years of existence.  Our bodies are perhaps unsure of how to break it down – we’ve got enzymes and mechanisms for digesting animal fats, but some Franken-fat with a new molecular structure is a different deal entirely.  What’s the result?  If you’re lucky, it won’t affect you in the long run. But over time, as you eat more and more of these modified fats, your body gets worse and worse at dealing with them, and there’s fairly good evidence that trans fats contribute to certain diseases, mainly heart disease.

Back when they figured out to hydrogenate liquid fats into solid fats, they proclaimed it as a triumph of science: no longer would we be forced to cook with lard or butter.  Just slap some margarine on that bread! Make your cakes and cookies with shortening and they’ll be healthier for you!  And now we’ve finally come to the end of a long road that taught us we may have been a little overzealous about proclaiming hydrogenation as a benefit to society.  That’s why you hardly see it in anything anymore.  Note that it naturally occurs in small amounts in animal products, and if you’re buying most any brands of grocery store peanut butter, you’ll find that one of the main ingredients is “partially hydrogenated vegetable oil” (to my ears, a death cocktail mixing the worst of two worlds, vegetable oils and trans fats, but that’s a story for another day).

Time magazine just came out with an article suggesting we have perhaps been wrong to demonize normal, saturated fats as we have over the last few decades.  Over these 50 years or so, very little evidence has come to support the claim that fats are bad for you, except in this particular case of trans fats. It again brings to the mind the question of when a new technology should really be proffered by “experts” as safe.  Who knows what will be next to go – unfortunately, we’ll have to wait on epidemiological data showing trends in diet and disease, and that could take decades more.

Regardless, the health craze of substituting real fats with fake fats has fallen pretty hard, and not a moment too soon.  Our health as a society, nay, a species, depends on a long-overdue mass acceptance of the cold, hard, solid-at-room-temperature facts.

Smells: Your Brain is way smarter than you think you are

Sorry for the confusing title, but let’s be honest: you, the person reading this, are essentially just a brain and spinal cord.  Your consciousness is your brain, and your brain creates your perceptions and your personality.  So really, your brain (you) is way smarter than you (your brain).  Particularly, your brain is really good at deciphering smells, and even though we’ve lost some of our sense of smell as evolutionary baggage, it’s still an amazing system.  Remember our talk on chirality a few months back?  We said that a molecule can come in more than one configuration and that your body is selective for each version.  Turns out that the way you smell has a lot to do with these various versions of molecules.

When you smell something, it’s because odorant molecules are drifting through the air from the substance into your nose.  If you smell pizza, it’s because molecules of pizza are flying off the pizza itself and eventually making their way into your brain where they activate certains neurons.  The molecules take a pretty short trip to your brain by getting picked up by the olfactory bulb and being transmitted to the limbic system.  Each of the cells that receive these smells and then transfer them are different from each other.

Currently, we believe that we have over 1,000 different genes for cells that pick up smell – in other words, 1,000 unique identifiers that each receive signals in a different way.  Imagine all the combinations you could have!  About 3% of our entire genome (all of our genes that code for what we are) is dedicated to smell identification, so it’s a pretty important set of genes.  Each unique collection of smells (pizza, rain, or hot chocolate, for example) all light up certain combinations of our smelling cells, and the result is that we smell that particular smell only when we encounter that particular substance.  When you smell a flower like in the picture above, a certain unique combination of cells is excited and they each transmit a signal at the same time to your limbic system.  The brain associates this smell with roses, so that the next time you activate this particular combination of receptors, you know that there is a rose nearby, even if you can’t see one.  If you smell fresh hot bread when walking by a sub shop, you automatically know it’s because there’s hot fresh bread nearby, or more unlikely, some certain combination of smells that activates the same set of cells.  Maybe this is why some people say that cilantro smells like soap?

So why is our brain way better at this than we think?  It actually has the ability to distinguish between two versions of the same odorant molecule.  A great example is that of limonene, which smells like oranges in one version, and like pine tree in another version.  See the two “versions” of this molecule to the right – they look pretty identical, don’t they?  To your brain though, they’re slightly different, and as such they’ll light up different combinations of cells in your brain to give you a particular smell that you can perceive consciously. There is a subtle difference between these two versions, which we sum up by the term “chirality.”  The first version can’t activate a cell that only accepts the second version, and vice versa.  We don’t even need to have 2 different molecules to give different scents — we could use the same molecule with all the same atoms but simply change the configuration!

Even though we’ve lost a great deal of our sense of smell, we still have so many unique identifiers for scents that we can keenly distinguish between a virtually infinite number of smells.  If I slapped down two vials of limonene in front of you, you’d be hard pressed to identify each version by sight, but your nose knows better.  Additionally, the idea of scents evoking memories has to do with the fact that the limbic system where your smells are processed is closely related to your memory function.  Any smell that you have come to associate with a particular idea or memory can easily light up the same neurons, provoking that memory to come forth from the deep recesses of your brain.

Whenever I smell Vienna Fingers, I think of my grandmother’s kitchen because she always had these delicious suckers hanging around, and man,  did my nose enjoy them!

Why Rock Salt bites for Melting Ice

Sorry for the strong language in the title, but it’s true: the rock salt you go to sprinkle over the icy sidewalk every year is actually a pretty mediocre substance.  Sure, it melts ice, but it’s not as efficient as other substances.  You’d be better off saving that salt for your next soup or gumbo, or whatever it is you’d like to cook.  Why is salt not that great at melting ice? We’ll delve into the very simple structure of salt to find out the answer, and then we’ll see what you should be using instead to get a much better, less slippery sidewalk!

You might already know the chemical formula for table salt is NaCl. It just means for every sodium atom, there is a chloride atom to go with it.  It’s a very simple substance, but it’s not a molecule — a term which is reserved for discrete groups of atoms (sugar molecules or water molecules, for example, are always the same and don’t associate with each other so much that we can’t separate them).  Salt is really an ionic substance, which just means that instead of having a discrete, separate “NaCl” molecule, it builds on itself, and each sodium bonds to a couple of chlorides, and each chloride finds a couple of sodiums.  The end result is a crystal, just like diamond, that’s highly ordered because all the atoms bond in the exact same way with all the others.  This is why coarse salt comes in those very geometrically ordered crystals — it’s the natural way that salt comes, all sharp lines and angles.

Pretty much any ionic compound like salt will dissolve in water because of this strange bonding behavior.  Water grabs each atom and pulls them apart from each other, and when all the sodiums and chlorides have stopped associating with each other, it’s dissolved and invisible!!  In other words, table salt in water separates into its constituent atoms (in this case, called ions).  As with all of science, it’s more complicated than that, but we’ll save that for another time.

The other key thing you might not know is that ice is not slippery.  Yes, ice is not slippery, but water is.  Ice on the sidewalk has a very thin layer of water on top of it, which makes it hard to walk on.  Any amount of pressure or heat creates this layer, so there’s literally no way for you to walk only on ice — you’re always walking on the buffer of water above it.  Now imagine dissolving some table salt into that top layer of water.  Just like in a glass of water, the atoms of salt will come apart and associate with water instead.  Since it’s probably below freezing at this point, the water would really, truly like to become frozen water, which some people call ice.  Thanks to salt, it no longer can.

The reasoning is pretty simple — imagine a little spherical sodium ion (just an atom, remember now) settling into some liquid water, swishing around with all the other moving cells.  When things become solid their movement is largely restricted, and water in particular tends to freeze into its own crystal structure.  Take a look at the picture to the right to see how water molecules arrange themselves when they become ice — there’s plenty of free space for ions to get in the way and prevent this structure from coming together.  Imagine a big ol’ sodium or chloride atom just forcing its way into those nice little bonds there — it’d be a little harder for the ice to form.  Because of the way water freezes, it’s less dense as ice than it is as liquid water, so ions have an easier time jumping into the fray and ruining ice’s day.

The only way water is going to freeze now is if it loses even more heat — it has to lose a little bit more heat, which means molecules will move around a little less, and at some point their energy is sufficiently low to allow them to bond to each other, albeit imperfectly.  Ice will do this to account for the disruption in bonding from the salt.  At 32 degrees, water wouldn’t freeze with salt in it.  So Mother Nature drops the temperature a few more degrees, and water is able to freeze again.  Yay!

Each mole of CaCl2 is more densely packed with ions, making it the better choice for melting ice.

So why is rock salt weaksauce for melting ice? It’s only made of two ions – sodium and chloride ions.  An equivalent amount (chemists use moles to compare “amounts” of things) of CaCl2, called calcium chloride, breaks apart into three ions — it’s 50% better at disrupting the bonds needed to make ice.  In fact, any ionic compound with more than just two atoms per formula unit.  A formula unit is just the smallest discrete “molecule” of a substance, except that ions make giant crystals instead of staying as separate molecules, like water or sugar.  Imagine if 100 water atoms could all associate to form a single giant water crystal — the formula unit would be H2O because that’s the formula unit that makes up the crystal as a whole.

There are many more ionic compounds that are more effective than rock salt, including ammonium sulfate and magnesium chloride.  In other words, when we buy rock salt because it’s the cheapest de-icer, we’re shortchanging ourselves.  We could be using a lot less “stuff” on our sidewalks while getting the same effect, or using the same amount compared to rock salt and get an even more effective result.

Winter’s grasp has finally let go of us, but keep these concepts in mind for next year – if you have to make a choice between rock salt and calcium chloride at the Get-rid-of-ice store, give it a little more thought.  You just might stretch your hard-earned dollars a little farther.

 

Salt Substitutes: Potassium is the new sodium

I love my salt substitute.  I love chemistry.  What do you get when these two collide?  With any luck, a really interesting discussion about potassium chloride.

Unless you’ve gone out of your way to try it, you’ve probably never tasted it (or noticed its taste).  It’s sold commercially to hypertensive (high blood pressure) customers, who don’t want the salt in their food to wreak havoc on their bodies (hint: it might not be).

In fact, there’s very little about KCl (the chemical formula for potassium chloride) that’s merely a substitute – the atoms it’s made of are equally important for our body as those in regular salt. Let’s see how KCl earns its place in your diet, and maybe you’ll show it a little love next time you run across each other.

First, let’s talk about properties.  KCl is white and crystalline just like its cousin, regular old table salt.  Take a look at the picture on the right — yeah, it’s the same periodic table you’ve seen a thousand times, but notice that Na and K are right next to each other.  This means their properties (melting point, solubility, etc.) are similar, which means that potassium will also want to bind with chloride just like sodium.  KCl doesn’t taste nearly as “salty” as table salt does, but it’s a similar compound in many ways.  KCl will also dissolve just like salt in water, so you can use it for soups or anything wet.

 

Ever studied the brain?  Your brain uses cells called neurons to send signals to your body.  It works by letting in sodium ions to your brain cells, which change the electrical forces around them, resulting in impulses that travel to your muscles as movement.  This seems like a good argument for eating salt, since the sodium we get from it is vital to our very existence, but there’s more to it: not only do sodium ions affect nerve impulses, but both chloride and potassium ions are vital to the mix as well.  Using KCl instead of NaCl is just as beneficial for your health in terms of the essential electrolytes (anything that dissolves to make ions, in our case, table salt or KCl) your body doesn’t just make on its own.

Have you ever gone out for a meal, dumped a ton of salt on it, and then checked the scale the next morning? To your horror, you may have gained a few pounds.  It’s not fat, but rather, sodium that attracts water and holds it.  Each sodium ion you ingest associates with water molecules, and since it takes some time for sodium to be excreted from your body, it contributes to water weight.  The effects disappear after a day or so.  KCl has no affinity for grabbing hold of water, so using a ton of KCl wouldn’t result in you gaining any water weight — a good idea if you’re headed to the beach pretty soon and you’re worried about your figure (I’m certainly not, but hey, I’m not judging anyone).

By extension, the fact that sodium absorbs  water means the water balance in your body is upset and your cells have lost some fluid — which is exactly why eating salt makes you really thirsty.  KCl doesn’t have this problem.

Let’s consider the lethal dose for sodium, which is 3 grams/kg of body weight.  If you weight 150 pounds, that’s about 68 kg, and you’d need to eat 204 grams, or nearly 7 ounces of pure salt for it to kill you.  It’s safe to say you can’t kill yourself from overdosing on salt – I’d be honored to know you if you could stomach more than an ounce.  KCl has a slightly lower lethal dose of 2.5 grams/kg body weight.  Without even doing that math, we know you’d have to eat at least 2 of those 3 ounce containers of Nu Salt in the photo above to kill yourself only 50% of the time.  So it’s pretty safe.  For reference, 10 grams or a third of an ounce of caffeine will put you six feet under — you could fit that much onto a spoon.

So we’ve established a great many things: KCl is as safe as salt, performs better for water retention, hypertension, and is entirely composed of two ions that you need to survive your day-to-day.  What’s the downside here?

It depends whether you like the taste of KCl.  I find it just fine — it has a slight cooling effect, a little metallic-y, bitter-y taste which is not unpleasant, and a slight salty finish.  It’s hard to describe unless you’ve tried it, but you can find any person on the street to describe what table salt tastes like.  So why not try something that’s off most radars, venture into some new territory, and give a little love to the cousin of table salt?  You just may find it suits your taste buds.

There are generally considered to be two major retailers for potassium chloride – Nu Salt, pictured above, is pure KCl — no salt, so use it liberally.  The other contender, Morton’s Lite Salt, is a 50/50 mix of regular table salt and KCl, presumably to mask the perceived bitterness of the KCl.  Even cutting your table salt intake in half might be considered beneficial, so this is a great option if you can’t stomach potassium chloride all by itself.  They’re both sitting in the spice aisle with the coarse kosher salt, organic whole-grain free-range sea salt crystals, picking salt, and of course, regular old table salt.  Both are a great way to get potassium into your diet, which is an easy nutrient to become deficient in.  Bananas and coffee have some potassium, and cream of tartar is chock-full of the stuff, but unlike table salt, there’s no go-to kitchen item that can refill your potassium supplies — except, of course, for the two products we just mentioned.  Try tracking your potassium intake for a few days, and you may just fine you’re not getting as much as you should — low potassium can definitely kill you, because it’s required for your body to send all of its complex electrical signals.

Ah, knowledge is truly delicious (and low sodium to boot)…

 

Radioactivity: All roads point to lead

If you take a look at the periodic table, you’ll notice that lead is element number 82.  Not coincidentally, every element with an atomic number greater than 82 is radioactive, meaning they’re unstable and prone to ejecting particles to seek stability.  It has a lot to do with the number of neutrons and protons in the nucleus; to keep each other in check, their numbers should be roughly equal.  If an element has too many neutrons, it’s at risk of shooting a particle away from itself to form a more stable substance.

Take a look on the flowchart at the right.  We see here that Uranium, at the top of the list, has an atomic number of 92, meaning it has 92 protons.  The number “238” refers to the sum of uranium’s protons and neutrons.  With some quick subtraction, we can deduce uranium has (238 – 92) = 146 neutrons.  Wowzers! It has about one and a half times as many neutrons as protons, so what could we say about the stability of uranium?  Well, if you’ve any inkling for radioactivity, you probably already know that uranium tends to decay and is therefore highly radioactive.  It’s the mystique of such heavy atoms that has placed these radioactive species at the forefront of science fiction, appearing in all sorts of fantastic gadgets like time machines (what was the element they needed in Back to the Future? Ah, yes, it’s plutonium, atomic number 94, just two doors down from uranium. No surprise there!)

You might be asking yourself, “so what kind of particle might uranium want to eject to become stable?” The answer is that it’s complicated.  Radioactive elements generally have 5 ways of ejecting particles — sometimes they shoot off an electron, sometimes they shoot off a proton, or they might try their luck at adjusting their neutron number.  You can see on this flowchart that uranium ejects an alpha particle, which is nothing more than a helium nucleus (helium has 2 protons and 2 neutrons, and since this is the nucleus, there are no electrons emitted).  If uranium shoots out two protons, it loses its identity as it drops its proton count down to 90.  Now it’s thorium!  Notice the huge amount of time listed there: that’s the half-life of uranium decay, meaning that in 4,510,000,000 years from now, a one pound sample of uranium will still be half uranium by weight. It takes quite a long time, but check out what’s next in the line-up.

Thorium ends up emitting an electron from its nucleus.  Wait, what?  There aren’t any electrons in the nucleus, so how can this occur?  It might blow your mind: one of its neutrons splits into a proton and an electron.  The electron is emitted while the proton remains behind.  Since we’ve added one more proton, our element becomes protactinium, and it happens in just a few weeks!

This series of events will continue for quite some time until it reaches the end of the line, which you’ll notice is Pb, or lead.  I don’t think it’s a coincidence that lead is the last non-radioactive element in the periodic table — by definition, radioactive elements will always spit out some particles until they become less and less unbalanced.  It just so happens that uranium will always, always, always eventually decay into lead.

So in a few trillion years from now when we’re mining the far reaches of outer space and living in Jetsons-esque societies on a hundred different planets, nearly all the uranium that exists today will be on its way to become lead.  If we find some elements that are even more radioactive than the ones we’ve already discovered, at least we have some consolation: all that lead converted from uranium will do nicely as a shield from x-rays and other radioactive energy.  Kind of ironic, huh?

Partial Zero Emissions: Let’s Catalyze some Converters!

After a rather depressing take on cholera, why don’t we investigate a magical component of every single modern car?  That would be, of course, the catalytic converter.  Have you ever seen the “Partial Zero Emissions Vehicle” sticker on a car?  The catalytic converter plays a huge part in a vehicle’s emissions.

You likely already know a catalytic converter is responsible for preventing toxic fumes from entering the air and atmosphere, thus lowering the environmental harm from massive automobile use.  It’s a fairly simple mechanism, but it’s absolutely genius, and worth exploring.  We’ll dive into how a catalytic works, what it’s actually converting, and how it almost magically turns terrible things into glorious, benign things.  Let’s do it!

When cars use gasoline, they produce carbon monoxide as a by-product.  You might know carbon monoxide, chemical formula CO, from your house, where it lies in odorless, colorless, tasteless waiting.  They make detectors so you don’t inhale it without even knowing, and end up dead.  So this is something we clearly don’t want to be breathing in, but cars love to release the stuff like a guy on a street corner dishing out flyers for his indie band.  The way to neutralize this, and indeed, many many other reactions in chemistry and all of life, is through what’s called a redox reaction.

Don’t let the name scare you: a redox reaction is really simple on the surface, but it’s a get a little confusing if you want to explore it.  We’ll keep it as surface-level as possible.  For now, just know that a redox reaction is a reaction where two different substances (maybe two different molecules) change their electrons around; the first molecule might give an electron to the second one.  That’s it. The word “redox” is just an abbreviation for “oxidation-reduction,” which just has to do with the state we assign to each molecule after the electron is switched around.  If you lend me five dollars, you’re the lender and I’m the borrower.  If I lend you five dollars, I’m the lender, and you’re now the borrower.  If I give you an electron, I’m the reducer, and you’re the oxidizer.  Don’t sweat this point too much; it’s not a big deal for our understanding.

From our beloved Wikipedia, here are the three things that happen in the converter:

1.  Reduction of nitrogen oxides to nitrogen and oxygen: 2NO_x → xO₂ + N₂
2.  Oxidation of carbon monoxide to carbon dioxide: 2CO + O₂ → 2CO₂
3.  Oxidation of unburnt hydrocarbons (HC) to carbon dioxide and water: C_xH_2x+2 + [(3x+1)/2]O₂ → xCO₂ + (x+1)H₂O.

Our first reaction makes oxygen and molecular nitrogen, both of which make up the air around us, so that’s great.  The second reaction makes CO2, which I suppose is good for the plants that use it for energy, but it’s not needed for us, and in fact it’s a waste product of our metabolism.  The third reaction is just like setting anything on fire: you mix the fuel and some oxygen and you will always make water and carbon dioxide.  So for the most part, we’re taking in unspent fuel and poisonous gases and releasing carbon dioxide, water, and oxygen, all of which are way less malicious.

At this point it’s worth it to wonder, “Just how do we get these reactions to take place?”  They can’t just spontaneously happen at such great speeds unless we have a catalyst, which is just something else that makes a reaction go faster.  Inside the catalytic converter, you’ll typically find platinum, a metal that is great for catalyzing these reactions.  A metal catalyst can work by bonding and then orienting molecules in order for, in this case, electrons to be swapped.  The changes in orientation the catalyst makes lets the reaction go much more easily, and when  our noxious fumes land on the platinum, these reactions can proceed!  Yay!

Notice how the precious metal catalyst in the picture to the right takes in 3 separate compounds, but releases three entirely different compounds after the reaction. And how about those partial zero emissions vehicles?  Well, their surface area is twice that of a standard converter and consists of multiple layers to ensure more efficiency conversion.  Of course, factors like the fuel injector and air intake also affect the emissions amount, but the catalytic converter is hugely important for the final step in the process.

One of the downsides to catalytic converters?  Along with platinum, other precious metals can be used for the reactions, which makes them enticing to thieves who can’t figure out how to nab your stereo system — you’ll pay a lot of money to replace a catalytic converter. But please, for the good of mankind, replace it if it’s stolen — because now that you know what your car is potentially putting into the air, you owe it to yourself and everyone else on the planet!