The bullshit about high fructose corn syrup (HFCS) is getting pretty thick. Health care professionals have cautioned us against over-consumption of the stuff, and the corporate public-relations jackals have swooped in to do damage control.
"It's made from corn," they say. "It's nutritionally the same as sugar."
This reminds me of that classic film, Thank You for Smoking, and it only goes to prove that you can support any claim, no matter how ludicrous, if you massage the data enough.
If the warm and fuzzy reassurances of the corn syrup industry have left you unconvinced that their gloopy crap is good for you or your family, then read on. I'm going to lay down the hard facts. HFCS may be sweeter than sugar, but when it comes to your health, it's not so freakin' sweet. At all.
Fact #1: HFCS Isn't the Only Problem Sugar.
Any sugar that contains fructose is especially problematic from a health perspective. Despite its name, HFCS isn't as "high-fructose" as you might think. Depending on the type, it's generally 42 to 55 percent fructose. The former is common to solid foods, and the latter to beverages. Just as the PR jackals claim, it's chemically similar to table sugar, which is 50 percent glucose and 50 percent fructose.
Sucrose is very similar to corn syrup.
Although these sugars don't have the extremely high glycemic index of raw glucose, they do cause a combination of hyper-insulinemia and aberrant intracellular metabolism, which in turn creates the double-whammy of lipogenesis (fat creation) and glycation (gummed up body proteins). More on all this later. For now, it's enough to know that fructose-containing sugars are not so good.
Fact #2: The source of the sugar makes all the difference.
With the faster gastric emptying [7, 9] and greater blood sugar swings compared to solid meals, liquids are themselves a consideration. Although the literature isn't unanimous on this, simply drinking one's calories creates a positive energy balance. That is, anyone who drinks his calories in fluid form is less likely to down-compensate his intake in later meals.
The natural regulation of daily energy intake gets disrupted. Although this can be used to one's advantage (e.g. bulking), it can also be bad. Whatever you might have heard, all calories are not created equal: carbohydrates as a class are more "fattening" than proteins.[6, 16, 17]
Sure, you can find data that HFCS beverages are not different in satiety value than sucrose drinks, or even milk,  but we really need to consider the type of nutrients in those drinks. If they all similarly create positive energy balance, I think I'll choose nutrient-rich milk.
Straight liquid carbs like high-fructose corn syrup or sucrose solutions are digested and metabolized in a particular way, and they're the number one choice of thirsty Americans. Sports supplement drinks and popular beverages are loaded with them. We've all read labels that say, "contains less than 5 percent juice." This is marketing-speak for "fake."
Fact #3: Metabolic mayhem ensues after HFCS ingestion.
Let me ask you this: where in nature could our hunter-gatherer ancestors quickly guzzle down 100 grams of sugar? You guessed it, nowhere. It just ain't natural. It astounds me that the human body can even deal with a Super Big Gulp. And actually, it doesn't deal with it very well.
The modern-day hunter-gatherer returns with his quarry.
When a human being quickly introduces that much sugar, his body does what it must: turn it into triglycerides (fat). I've seen some disturbing blood work after ingestion of a fat-free, high-fructose meal, in which the subjects' blood values looked like they had just wolfed down some fried chicken. How can this be?
Fructose really turns up the lipogenesis by bypassing the most important regulatory enzyme in our carbohydrate biochemistry, PFK-1. This supplies our bodies with a bountiful supply of acetyl-CoA and glycerol, the building blocks of fat.
Fructose in the cellular metabolism: follow the yellow fat road.
Fact #4: Fructose gums up your tissues.
Compared to glucose (which you hardly ever find all by itself in the diet), fructose has a much greater tendency to glycate (or glycosylate if you prefer) surrounding proteins. [12, 21] You've probably heard of glycosylation before. Glycosylated hemoglobin (HbA1c) is a common marker of past glucose tolerance, used to test diabetics.
Glycosylation is more than an indicator of someone's blood sugars running high, however. As a broader phenomenon, it's been linked to disrupted cell function and aging.[12, 13] I used to think fructose appearance in the bloodstream was inconsequential (the liver converts most of it to glucose), but in today's HFCS and sucrose-crazy environment, that little 4-8 mg/dl rise in blood fructose day-in and day-out could become an issue. I don't want my DNA or collagen damaged by glycosylation.
Fact #5: Fructose is a big problem if you have metabolic syndrome.
Fructose ingestion is especially problematic for the 10 to 30 percent of the population (and 6 percent of college students) who are already insulin-resistant due to metabolic syndrome.[14, 15] This is a collection of visceral fat accumulation, high triglycerides and LDL-cholesterol, low HDL, high blood pressure, and poor glucose tolerance.
It can creep up on middle-aged guys especially. Their central body fat (visceral fat behind the abs) has a higher turnover rate, which lends some extra fatty acids to the new "building blocks" made available by ingested fructose. The end result is even greater lipogenesis, taking place in an individual who already has surplus fat stored in the worst possible place. Fat begets fat. It's a vicious cycle, which needs to be turned around by sugar reduction, exercise, and medical intervention.
Fact #6: HFCS is fattening, and it's everywhere.
From both a biochemical standpoint, as we've discussed, and from an epidemiological standpoint (obesity trends mirroring HFCS introduction in the food supply), high-fructose corn syrup appears to be a problem.[5, 18]
Epidemiological evidence is not cause-and-effect, of course (a fact the news media overlooks at times), but the HFCS-obesity relationship is suspicious indeed. HFCS consumption has grown 10-fold in recent decades to a whopping 9% of the U.S. calorie intake.[4, 5] And we all know what's happened to the obesity numbers in that time period.
I can barely comprehend that nearly one in ten things Americans now ingest is HFCS. My "health food" granola bars are jam-packed with it. I even tasted some sweetness in some chicken breasts my wife bought. I looked at the label, and you can guess what I found on the ingredients list. HFCS in Chicken breasts! Is nothing sacred?!
But there's more to corn syrup making people fat than just the fact that people eat more of it than ever. We have the uncontrolled glycolytic inundation that we discussed earlier, and here's another fact: fructose actually induces lipogenic enzymes.
According to one study, "long-term absorption of fructose... causes enzyme adaptations that increase lipogenesis and VLDL secretion, leading to triglyceridemia, decreased glucose tolerance, and hyperinsulinemia."
That's right, exposure to fructose prepares the body to do the last thing you want it to do: convert that fructose into fat and store it.
And although there's reason to believe that trained individuals with partly depleted glycogen stores have some capacity to resist fructose's lipogenic effects, even exercise doesn't look like perfect protection, at least in rats: "we conclude that hepatic lipogenic enzyme induction by high carbohydrate meal feeding may be inhibited by exercise training [but] that a fructose-rich diet may attenuate this training-induced down-regulation."
Just say no.
In sum, when something looks like a health problem, and acts like a health problem, guess what? It's a health problem, and public relations be damned. I hope this article has helped you cut through the confusion. Share these facts with your family the next time you see a commercial thanking you for guzzling corn syrup. Corporations have to realize that there are thinking men and women in this world who see their bullshit for what it is, and can answer them back appropriately.
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