Railroad tank car transporting high fructose corn syrup (Photo credit: Wikipedia)
What reeks un-paleo more than something called ‘high fructose corn syrup?’ It’s excessive, it’s processed and, as if that weren’t enough, it’s extracted from a mass-produced grain. It’s also heading the list of commonly-used artificial sugars. I don’t mean ’0-calorie’ sweeteners which are easy enough to avoid, but the sweeteners in most popular supermarket foods, from Coke to white bread. But that shouldn’t be a problem on the paleo diet, should it? We steer clear of the processed stuff anyway.
However, the harmful effects of high-fructose corn syrup aren’t just from the fact that its corn-derived and chemically altered; part of the responsibility falls on the concentrated fructose— a strain of sugar that we naturally associate with fruit. What are fruit carbs doing on the paleo diet’s naughty list? To make sense of that, you’ll have to take a look at where this not-so-sweet sweetener comes from, and the relationship that it has with your body.
It’s Corn processed Twice Over
As a paleo dieter, you’ll learn soon enough how bad corn is for you. Most of the corn you find is genetically modified; on top of that, it gives you far too much starch and inadequate protein. Now, take that corn into a factory and converted to even more concentrated cornstarch. Then treat it with hydrochloric acid and microbial enzymes to create corn syrup— a well-known ingredient in processed food because of its capacity to retain moisture, and to keep your white bread fluffy and soft (preservatives, anyone?). Sounds bad enough, right?
Well, high-fructose corn syrup (HFCS) takes it a step further. Corn syrup is made of short-chain sugar molecules called oligosaccharides, which aren’t nearly as sweet or as soluble as the monosaccharides (single-unit molecules) fructose and glucose. That’s why it needs even more enzyme-induced breaking down to reach that stage. Of course, by this point, you can regulate the chemical activity to get the glucose-fructose ratio you want. As such, you end up with strains of HFCS whose levels of sweetness are determined by the amount of fructose. It’s like we no longer need to worry about the digestion process— or, for that matter, the tasting process—anymore, since it’s being done in labs for us.
Well, why not simply measure out regular cane sugar, honey or molasses as sweetening agents, then? Why go through the hassle of chemically tampering with corn when natural alternatives are available anyway? But there’s the rub: these natural alternatives aren’t as available as corn. It comes down to ‘economic feasibility,’ as with most commercial crops. Sugarcane or beetroot isn’t as multipurpose or as high-yielding as corn, after all. Hence, while corn production gets subsidized, sugar production gets taxed. In the process, the food industry’s main sweetener becomes a chemical mix that, on some days, makes table sugar look nutritious by comparison.
It’s High-Fructose Food for a Low-Fructose Body
Table sugar, or sucrose, isn’t all that great. It’s a molecule made up of both glucose and fructose, which is broken down into both during digestion. While sucrose is available in nature, our paleo ancestors definitely couldn’t shovel concentrated teaspoonful into their tea as we do now. So how is that very different from HFCS , which is about as sweet? Apart from the fact that we get to digest the sucrose ourselves, not very. But that difference alone is still what makes sucrose the healthier choice (though the paleo diet discourages both). As anti-paleo as sucrose may be, large quantities of independent fructose— as is present in HFCS— is even worse.
Our bodies don’t use fructose for energy production— the primary player in cellular respiration is glucose. That’s why glucose and fructose are metabolized independently, despite being similar molecules. While they are both processed through the liver, glucose, playing the more active role in the body, is kept in check by insulin, with excess glucose being converted to the inactive form glycogen. Also, glucose is transported and metabolized throughout the body.
Fructose, however, doesn’t have an insulin check and is converted almost entirely by the liver. Therefore, the more independent fructose you absorb, the more pressure your liver takes on. Furthermore, because this sugar isn’t used up in respiration, all the fructose you ingest is converted directly to stores of fat, alongside excess glucose.
This tells us two things: first, our bodies aren’t equipped to handle large quantities of fructose; from which we can infer that the original hunter-gatherer diets didn’t have a lot of fructose to begin with. Secondly, independent fructose is far easier to absorb than sucrose that needs natural digestion; so even if the glucose-fructose balance in HFCS is similar to sucrose, the syrup is still better at enabling problems like liver disease and obesity. Let’s not even go as far as HFCS!
Now, that first point might strike you as a little odd, since fructose is, after all, naturally available in fruit. Remember, though; plants too, use glucose and not fructose for cellular respiration and growth. At the other end of the plant’s functions, starch is how they store that sugar. Fructose does play its part in plants; it is a stored sugar; and more importantly, it makes fruit flesh pleasant for animals to eat and disperse the seeds. Fructose is also a component of the nectar that attracts pollinating insects. Both of these are key processes in the reproduction and proliferation of a flowering plant— but neither dispersion nor pollination applies to humans. That didn’t matter for the original paleo eaters, anyway. They ate apples and berries as they came into season, utilized the glucose and starch, and stored the smaller quantities of fructose as a secondary energy source. Our physiology still treats fructose that way; unfortunately, it didn’t count on us guzzling that one monosaccharide by the pound.
The Risks of HFCS:
The lack of filtering for fructose by our bodies, coupled with the economic ease of making and using this ‘sweetener,’ means that HFCS has had ample time to contribute to many of the health disorders that the modern-day dieter faces. As aforesaid, it overworks the liver, eventually leading to the same results as excessive alcohol consumption: liver cirrhosis. And if it’s hindering the liver’s functions, HFCS is messing with the neighboring pancreas’ work too, compromising insulin secretion and increasing the risk of a disease that we’re all too familiar with: diabetes.
The inability to metabolize fructose isn’t the only thing that adds to adipose deposits and obesity; this molecule wreaks more havoc than that. Fructose acts as a leptin inhibitor— leptin being the hormone that regulates appetite, the voice of reason to our cravings. Princeton University has experimentally proven— albeit with rats— that excessive fructose disrupts the feedback loop between leptin and the food you need to replace after respiration, enabling you to crave more indigestible carbs without so much as a prick of your intestinal conscience. And we all know that obesity and excess fat are first cousins to clogged arteries and heart disease.
All of that being said, note that the operative problem isn’t ‘fructose’ but ‘high fructose.’ The paleo diet— and common sense— can’t stress enough on the fact that an excess of any food group or type is a health hazard. Overproduction of un-paleo grains and legumes, the replacement of seasonal and organic fruits with GMOs, and the rising popularity of processed, apparently ready-to-eat food are all examples of that. High-fructose corn syrup and its consequences are simply a demonstration of what those problems can do together, condensed to a spoonful of ‘sweetener’. However, it’s very easy to pin down fructose as the bad guy along the way, considering that it’s to blame for the eventual effects.
Does that mean we steer clear of fructose? If it’s in the form of anything called ‘HFCS’ ‘corn sugar,’ ‘corn syrup’ or ‘glucose-fructose syrup’ in your ready-made pastries or tinned fruit, then yes— run! But from your grape vines or strawberry bushes? Why not? That’s not high-fructose corn syrup, after all; that’s a small dose of some good old wholesome fruit sugar, as paleo as they come.
More at: Paleo Guide To High Fructose Corn Syrup (HFCS)
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