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10 Reasons I Frown On Fructose

In this lesson, I’ll focus on two pervasive ingredients behind our collective declining health: sucrose and high fructose corn syrup (HFCS). With this lesson you will discover why you should be concerned about excess fructose consumption, and how it directly relates to the health of your digestive tract if you have gluten intolerance or an irritable bowel.

Table of Contents:



Hold Your Horses: Please Read and Think Before You React

This is a difficult topic to write about given the current reactionary nature of the Internet. There are outspoken activists that make bold claims to the great evils of high fructose corn syrup. Some of their claims are misguided and exaggerated, or at least expressed in a manner that suggests an unknowing lack of understanding.

This is unfortunate because such reactionary behavior marginalizes legitimate concerns. I will address legitimate, reasonable concerns about fructose and high fructose corn syrup (HFCS) and support those concerns with evidence — with specific references to research published in legitimate and reputable peer-reviewed medical journals.

One common mistake is to assume HFCS is the same as fructose, but it’s not. It is closer to sucrose (table sugar) than it is to pure fructose. Similarly, people often apply the negative research on fructose to HFCS but not to sucrose. Often this is a mistake, as sucrose contains 50% fructose and deserves plenty of blame as well.

However, there are legitimate reasons we should be even more concerned with HFCS than we are with sucrose, despite the short-sighted mainstream media’s attempts to suggest otherwise. I will give you very specific, concrete reasons for this legitimate concern.

To be clear: I’m targeting the excess fructose we consume via added sugars like sucrose and HFCS. The relatively small amounts of fructose embedded with fiber in whole fruits and vegetables serve as a marker of healthy food for our taste buds. The fructose in fresh, whole fruit alone won’t hurt most people as long as they consume it in its whole, natural form and in reasonable moderation.

What Is Fructose?

Fructose is a monosaccharide, which means “one sugar.” This means it is a simple sugar and one of the most basic units of a carbohydrate. Fructose is found in many plants where it is usually bound to another monosaccharide, glucose, to form sucrose, which is a dissaccharide, literally meaning “two sugars.”

Monosaccharides are easily absorbed into the bloodstream without any processing. Disaccharides like table sugar must be broken down into two separate monosaccharides before those molecules can be absorbed.

What Is High Fructose Corn Syrup?

Corn refiners take corn starch, and in a chemical process, convert it to a glucose syrup. Then in a second chemical process, they invert about half the glucose to fructose. Because corn syrup originates as a substance consisting of a single monosaccharide (glucose), the resulting glucose and fructose molecules are not bound together. This means the human body can instantly absorb them without any enzymatic activity.

Over the last decade the use of the word “natural” has become a little tired and untrustworthy, and justifiably it has become the target of sincere skepticism since the term isn’t well-regulated on food labels. But it’s worth noting that compared to table sugar, HFCS is definitely not natural by any reasonable definition. Sucrose exists naturally in the world within fruits and vegetables, particularly in sugar cane and sugar beets.

High fructose corn syrup does not exist naturally anywhere in the world. It is a synthetic substance created from corn starch using a chemical process.

Unlike sucrose, high fructose corn syrup in isolation is, strangely, not available to the public. You can walk into your local grocery store and buy sucrose, glucose, fructose, honey, agave nectar and even regular, pure glucose corn syrup. But you cannot buy high fructose corn syrup by itself.

Is Sucrose Different From High Fructose Corn Syrup?

In one word, yes. They’re different in two subtle but significant ways, and neither of these differences are disputed by the Corn Refiners Association.

First, sucrose contains glucose and fructose molecules bound together, while HFCS contains unbound molecules. When you eat sugar, your body must break this bind before it can absorb the separated molecules. High fructose corn syrup contains free molecules. The fructose and glucose molecules are not bound together, so your body doesn’t have to break any bind before absorbing them.

One capability provided by these free molecules is that they allow for a sweetener with unequal parts fructose and glucose. And that leads us to the second difference between sugar and HFCS.

Because of its 1-to-1 bound molecules, sucrose is always 50% fructose and 50% glucose. Manufacturers claim most high fructose corn syrup contains about 55% fructose and 45% glucose. By this claim, HFCS contains nearly 20% more fructose than glucose, and HFCS contains about 10% more fructose than an equivalent amount of sugar.

However, as you’ll see below, objective laboratory analysis of real world HFCS has revealed that HFCS often contains 60% or more fructose to 40% or less glucose.1 That means that high fructose corn syrup often contains 20% more fructose than the equivalent amount of table sugar.

This is an instance where the CRA uses a bit of sleight of hand. Because sugar and HFCS have “about” 50% fructose and 50% glucose — meaning not exactly 50% each, but “close enough” to say about 50% — and because, after your enzymes break the binds in sucrose, your body absorbs roughly the same amount of the same molecules (fructose molecules and glucose molecules), the CRA likes to state that your body treats sugar and HFCS as “basically” the same. But, as you can see, “about” the same and the same are not, well, the same. Look closely at their propaganda and notice their use of the word “basically” and “about.” The devil’s in the details, I guess.

This might all sound nit-picky, but there are consequences to these subtle differences.

The CRA might respond that some forms of HFCS might consist of less than 50% fructose, such as the forms used in breads and yogurts. However, most products use the higher fructose version, and according to the research journal Obesity, these products often contained closer to 60% fructose rather than the claimed 55% fructose.1

Here Comes The Money Machine

If fructose and HFCS is so bad, why is it so difficult to make this claim and stand by it without taking heat and criticism?

Health-conscious people — including health researchers, nutritionists, dietitians and medical doctors — have been blasting the use of high fructose corn syrup in drinks and packaged foods for years now.

After profit growth began to suffer from this bad press, the Corn Refiners Association responded with an expensive promotional campaign in which they argue the body sees high fructose corn syrup as another form of sugar and that HFCS doesn’t have any inherent negative properties beyond those that occur with the excess consumption of natural cane sugar.

In recent years, the Corn Refiners Association and its buddies like the National Corn Growers Association have spent millions of dollars lobbying congress. They’ve even written and submitted new laws and tried to pass them, like a law giving them the right to label HFCS “corn sugar” instead of HFCS (despite extensive lobbying, it didn’t pass).

They’ve sent expensive, glossy and persuasive brochures to medical doctors, they’ve produced and promoted elaborate propaganda websites, and they’ve spent millions of dollars on misleading television commercials inaccurately representing their opponents’ positions.

They pay $500,000 a year to Dr. James Rippe to produce research supporting their argument that high fructose corn syrup isn’t less healthy than sugar.

The purpose of this expensive and meticulously organized propaganda machine is to persuade everyone that high fructose corn syrup (HFCS) isn’t unhealthy… or at least isn’t less healthy than plain sugar. Sadly, the reason they’ve spent so much time, money and effort on this propaganda machine is that they do have something to hide. It might be subtle in some ways, which makes it easy for them to demonize and ridicule their opponents, but despite their very expensive effort to persuade otherwise, the problems do exist.

10 Reasons I Frown On Fructose

Let’s go over the reasons I frown on fructose. I’ll begin with items that apply to all commonly added sugars in general, as collectively they’re the primary culprit to our excess consumption of fructose. Then I’ll cover specific problems with fructose alone. Then the latter reasons address why we should have specific concerns with high fructose corn syrup.

1. Even If “Sugar Is Sugar,” It’s Still Bad

“Sugar is sugar.” This is a defense the Corn Refineries Association leans on when they defend high fructose corn syrup. A recent movement of serious and legitimate doctors and researchers want to see people categorize added sugar as a toxic substance, and while some may see this move as extreme, it is indisputable that added sugars are to blame for a surprisingly broad range of health problems and weight problems… far more than most people realize. The CRA doesn’t deny this fact; they just try to point out that the problem is the same whether it’s a matter of sugar consumption or HFCS consumption.

So when the Corn Refiners Association repeats the “sugar is sugar” mantra, it isn’t a very compelling argument. Simply put, yes, they’re both a type of sugar… but sugar is bad and most people eat too much of it, no matter what the source. Seeing it added to so many packaged products is just plain bad for public health.

The development and increased use of high fructose corn syrup — which has occurred because corn refineries make it so cheap for product manufacturers, and because a syrup is easier to handle and manage than a crystalline powder — has correlated with our increased consumption of sugar.

In addition, despite their insistence, not all forms of sugar are created equal.

2. A High Fructose Diet Increases Obesity Risk

In the March 2011 edition of the research journal Diabetes, Obesity and Metabolism, researchers from the Oregon Health & Science University School of Medicine published their findings that your brain responds very differently to fructose than it does to glucose.2

Glucose consumption triggered activity in the the cortical brain control areas, the areas believed to be active in engaging appetite control. Fructose consumption did the opposite: it suppressed activity in those areas.

This research corroborated animal studies that suggested fructose increased the risk for obesity by suppressing appetite control.

So by maintaining a high fructose diet you may be compromising your ability to exercise appetite control. Remember, according to laboratory analysis, HFCS often has around 50% more fructose than glucose in it.

3. Fructose Stresses Your Liver And Increases Disease Risk

Unlike glucose, which is readily used by most cells in your body, fructose is primarily metabolized by only your liver. This is why fructose alone doesn’t have as high a glycemic index as glucose alone. When you consume something with fructose in it, it must go to your liver to be converted to glucose or stored as glycogen.

But what happens when you consume foods with added sucrose and HFCS? The fructose overloads your liver and instead of producing glucose or storing glycogen, it produces cholesterol and triglycerides. This is a fact — one which nobody disputes.

To directly quote a 2007 paper in The American Journal of Clinical Nutrition: “Hepatic [liver] metabolism of fructose favors lipogenesis [the production of cholesterol and triglycerides], and it is not surprising that several studies have found changes in circulating lipids when subjects eat high-fructose diets.”3

Trying to process large amounts of fructose strains your liver. Remember, when you eat packaged foods with added sugar you’re eating several times the fructose our bodies evolved to handle. This may compromise your liver’s ability to detoxify and heal itself.

The result is that, according to several studies, the regular consumption of added fructose increases your risk for dementia, depression, heart disease, obesity, liver failure, tooth decay and more.

These facts about fructose are not under dispute. Nobody — including the CRA — will deny them. Instead the CRA will try to deflect the matter by claiming that any of this research will apply to sucrose (table sugar) just as much as it applies to HFCS.

4. Fructose Can Cause Irritable Bowel Symptoms

Fructose is often fermented by yeast or bacteria in your small intestine. Bad bacteria feasts on the fructose and produces gas, inflating your intestinal tract like a balloon. When your intestine inflates like a balloon, bad things happen. Not only does this cause gas and bloating, but it may affect motility and absorption, causing foods to pass through your small intestine unabsorbed and causing diarrhea.

While excess sugar consumption may trigger this no matter the source of the sugar, because the fructose component of sugar is the culprit it’s perfectly reasonable to anticipate that foods with sugars containing a higher percentage of fructose will cause more problems. In fact, the evidence supports this claim.

The February 2010 edition of the Journal of Gastroenterology and Hepatology published a study wherein the researchers concluded, “The low FODMAP diet provides an effective approach to the management of patients with functional gut symptoms. The evidence base is now sufficiently strong to recommend its widespread application.”4

So what is a low FODMAP diet?

The low FODMAP diet is not a fad diet or a weight-loss program. It is a prescription diet for people suffering from functional gastrointestinal disorders. Functional disorders are conditions where the origin of the symptoms is not identifiable. Irritable Bowel Syndrome is the most common condition treated with the FODMAPs diet.

FODMAP is an acronym for “Fermentable, Oligo-, Di-, Mono-saccharides And Polyols”. In this diet, you remove all sources of foods containing FODMAPs and then re-add them one at a time to determine the source of irritation. So what are these FODMAPs? They are sugars and sugar alcohols poorly digested by some people’s upper small intestine. These include foods high in fructose (certain fruits, honey, HFCS), lactose (dairy products), fructans (wheat, onions, garlic), galactans (legumes and lentils), and polyols.

When these sugars and sugar alcohols go undigested, they feed bacteria, causing excess bacterial growth and fermentation. Bacteria are organisms that live in your gut, and those living organisms produce gases and new substances as part of their own survival. The result of an excess of these by-products is bloating, cramping and flatulence.

Much of the bloating, cramping and pain involved in IBS results from intestinal distension, where the by-products of this fermentation expand or inflate the muscle tube that is your small intestine.

For more about FODMAPs and the FODMAPs diet, visit these resources:

Stanford Hospital Low FODMAP Diet Handout (PDF)
Low FODMAP diet for Irritable Bowel Syndrome

5. Fructose Increases Your Risk For Gout

Gout is a recurrent and acute form of inflammatory arthritis. In two recent studies published in peer-reviewed medical journals, researchers determined that fructose consumption significantly increases the risk of gout. In the first study, researchers specifically blamed the consumption of soft drinks with HFCS for the meteoric rise of gout cases in recent years.5 Another study in the same year suggested that fructose-rich beverages also increases gout risk in women6, though they point out that in general, gout risk is still much lower in women than in men.

The Mayo Clinic — by most reasonable perspectives a reputable medical organization — explicitly forbids drinks sweetened with high fructose corn syrup on their gout diet: Gout Diet: What’s Allowed, What’s Not7

HFCS-sweetened beverages have more fructose than sucrose-sweetened beverages, per serving. This is a fact. If you consume large amounts of HFCS-sweetened beverages instead of sugar-sweetened beverages, you consume larger amounts of fructose and increase your risk for gout.

6. Fructose Is Biologically Unnecessary

To quote the American Journal of Clinical Nutrition again: “Fructose is an intermediary in the metabolism of glucose, but there is no biological need for dietary fructose.”3

There is no biological or dietary need for fructose. Your body just converts it to glucose so it in can use it. You can consume glucose directly or your liver can create glucose from protein in your diet. In fact, you’re just putting undue stress on your liver by making it perform the conversion of fructose to glucose.

7. Sorry CRA: HFCS IS Different From Table Sugar

Sorry CRA: the science says HFCS is different from sucrose.

The Corn Refinery Association tries to suggest that consuming High Fructose Corn Syrup doesn’t have any more of an impact on your health than basic table sugar, which is sucrose and is equal parts glucose and fructose. Unfortunately for them, despite the claims made by their ads and their propaganda websites, and despite many in the mainstream media being naive suckers for the CRA’s expensive campaign, the real evidence reveals there is a difference.

Before we get to the verifiable scientific research published in legitimate medical and research journals, please note the previous item, Fructose Stresses Your Liver And Increases Disease Risk, and my introduction explaining the difference between sugar and high fructose corn syrup.

First, in 2007 the American Chemical Society published their discovery that beverages containing high fructose corn syrup contained “astonishingly high” levels of compounds called reactive carbonyls.8 Reactive carbonyls trigger cell and tissue damage, and are closely associated with diabetes.11 It’s worth noting these reactive carbonyls occur in much higher concentration when HFCS is used in carbonated beverages than in non-carbonated beverages.

Reactive carbonyls are not in table sugar, because the glucose and fructose molecules in table sugar are bound together. In HFCS, the glucose and fructose molecules are free from each other. It’s these free molecules that allow for the presence of the reactive carbonyls. As I mentioned earlier, the CRA likes to say that your body sees sugar and high fructose corn syrup as “basically” the same (again, notice how they protectively use the qualifying “basically” here). However, before your body sees them as the same, it must break the bond between glucose and fructose in table sugar. Those molecules must be separated to be absorbed. In HFCS, these molecules are already free from any bond.

It appears the human body doesn’t like artificially freed molecules in the diet.

Second, a 2009 study published in the Journal of Clinical Investigation found that, to quote directly, “Consuming fructose-sweetened (not glucose-sweetened) beverages increases visceral adiposity and lipids and decreases insulin sensitivity in overweight/obese humans.”9 To translate, this means their peer-reviewed, human-based controlled study found that beverages sweetened with fructose instead of glucose 1) increased fat on the stomach and torso, which is the most dangerous and consequential fat on your body, 2) increased triglyceride levels in the blood, and 3) decreased insulin sensitivity, which is what happens when you develop type 2 diabetes and/or metabolic syndrome.

The Corn Refinery Association will be quick to point out that this study involved using fructose exclusively and compared that to using glucose exclusively, whereas HFCS is part fructose and part glucose. However, the claim for high fructose corn syrup is that it is 55% fructose and 45% glucose.

Whenever those numbers are stated, they’re often qualified with a word like “about.” An analysis of the sugar content in popular beverages reveals why they protectively use the term “about.”

Third, in an April 2011 issue of the research journal Obesity, researchers used high-performance liquid chromatography (HPLC) to do an objective analysis of the sugar content and fructose percentage of several popular beverages. What they found was that 1) The beverage almost always contained more total sugar than the label stated, and that 2) the high fructose corn syrup often consisted of a higher percentage of fructose than the corn syrup industry claims.1 The average fructose percentage of the tested HFCS was 59%, not 55%, and some results were as high as 65%.

This means that people consuming significant amounts of foods made with HFCS are consuming significantly more fructose than people consuming products made with cane sugar or beet sugar. Remember, the danger of consuming large amounts of fructose is not disputed by anyone.

Combine this data with the fact that manufacturers love to use high fructose corn syrup instead of sugar because it’s much cheaper, it’s much easier to handle, and it provides a longer shelf life for their products… and you have a whole culture consuming far more fructose than they consumed when they ate products sweetened with just straight sugar.

8. High Fructose Corn Syrup Isn’t Found Anywhere In Nature

On the HFCS propaganda websites, the CRA loves to state that HFCS comes from a natural grain — corn. They also love to point out that high fructose corn syrup meets the Food and Drug Administration’s requirements for use of the term natural.

Technically, HFCS does fulfill the FDA’s loose definition of what can be called natural. This is because nothing artificial is added to it that stays in the final resulting substance.

But notice that they don’t say, “the FDA considers HFCS natural.” Why? Because they don’t.

When the FDA was queried on HFCS, a representative explicitly stated that the FDA didn’t consider products with HFCS to be natural. Their reasoning was that HFCS was manufactured with “artificial fixing agents.”10

To be honest, both the FDA and the USDA need to take more steps to clearly define the term ‘natural’ and where it can be used, but that’s for another discussion.

Despite the CRA’s contentions with these statements from the FDA representative, the market clearly agrees with the statements made by that representative. When Kraft Foods and Cadbury Schweppes faced lawsuits after they used the term ‘natural’ on the labels of beverages containing HFCS, they relented and removed the word ‘natural’ from those labels.

The Corn Refinery Association loves to lobby for fewer regulations of their manufacturing methods and business practices, claiming the free market will keep them honest and fair.

Well, the market has spoken, and the market does not see high fructose corn syrup as “natural.”

But as I said earlier, there is one simple and indisputable way to gauge just how natural HFCS is. Simply ask the question, “Does high fructose corn syrup exist anywhere in nature?”

The answer is, unequivocally, “No.”

Corn refiners take corn starch, use a chemical process to convert it to a glucose syrup, then use another chemical process to convert 55% to 60% of that glucose to fructose. They do this because fructose is much sweeter than glucose. As the FDA pointed out, they use “artificial fixing agents” in this process.

Don’t be a sucker for the CRA’s big money propaganda: High fructose corn syrup is not natural.

9. The Consequences of High Fructose Corn Syrup Being So Cheap

This is a troubling fact: We consume more sugar than ever before because HFCS is so cheap and easy to handle. In the mid seventies, the average soft drink size was 8 ounces. Today it is 20 ounces. This is largely because soft drinks are sweeter and cheaper than ever before, and that is because HFCS is so cheap and easy to handle, compared to cane sugar.

Note that this may sound contentious, but nobody in the food industry denies this. The CRA will just spin some of these statements as HFCS being “more economical.”

HFCS is far cheaper than cane sugar because we grow an abundance of corn in the United States, and corn farmers are heavily subsidized. In addition, manufacturers like syrup better than a crystalline powder because it is cheaper and easier to transfer, store and utilize in a variety of product formulations. Last of all, HFCS works as a preservative, which allows manufacturers to provide products with a longer shelf-life.

All of this results in a comical link on one of the CRA’s propaganda websites. The CRA website links to an NBC Nightly News segment where Dr. Ludwig of the Harvard Medical School states that, “There is indeed little difference between high fructose corn syrup and table sugar.” Once again notice that it doesn’t say zero difference, just a little difference. I’ll have more to say about that “little” difference later. But it’s also worth noting that Dr. Ludwig has since stated that he was quoted out of context and that he doesn’t like how the CRA is using his words in their argument.

But if you watch the entire segment and don’t just cherry pick the one phrase that can be interpreted to mildly boost the CRA’s desperate defense, you find Dr. Ludwig stating things like: HFCS is so cheap, easy to handle and effective in making products more appealing that “food suppliers have the incentive to put it into virtually all processed products, from sugary beverages to the coating of chicken fingers.”

In other words, added sugars are now far more pervasive in food manufacturing because of how cheap and easy to handle HFCS happens to be. Yay?

The segment then continues to point out how beverage serving sizes have increased with the growth of the corn syrup industry, and that a typical 20 ounce soda contains 17 teaspoons full of sugar, all from HFCS.

The CRA made a big deal about this news segment, like it somehow vindicated them. For some reason, I imagine the Three Stooges managing their public relations department the day that segment aired on NBC.

Now… regarding the “little” difference.

While the differences here are almost negligible in a single teaspoon, when you expand that out to days, weeks, and years of consuming juices, sodas and packaged foods with high fructose corn syrup instead of cane sugar, you increase your risk for obesity, diabetes, heart disease and further problems just through decreased insulin sensitivity and increased calories by consuming products made with high fructose corn syrup instead of cane sugar. Why? Again look at the fructose research — which nobody denies — and look at how much more fructose high fructose corn syrup has compared to cane sugar.

The CRA loves to deflect this fact because the difference is so little when you consider a single small sample. But again, what happens when you consider the accumulated difference of the literal tons of HFCS consumed over the course of a few years? The CRA will respond that we don’t know, because we don’t yet have a long-term study evaluating this exact matter. Unfortunately for the CRA, plenty of us are capable of exercising some common sense instead of waiting for the studies to be executed and published against the will and deep pockets of the corn industry.

10. High Fructose Corn Syrup Signals Poor Quality Products

This is my own personal opinion and if anyone wants to state that this is purely subjective — by golly, you’re right! But one of the biggest problems with seeing high fructose corn syrup on the label of a product is that it suggests the company who manufactured that product is more interested in cutting corners to make an extra buck off of you than it is interested in creating and distributing a high quality product.

The first thing I think when I see ingredients like high fructose corn syrup or hydrogenated oils on a label is: where else did they cut corners to mass produce this product and improve their profit margins? What else is probably wrong with this product and the practices of its manufacturer?

If a product contains sugar instead of high fructose corn syrup, it isn’t necessarily more healthy. Added sugar is bad, no matter the source. But the occasional treat won’t kill you. When you decide to have an occasional treat, I encourage you to enjoy a higher quality treat. And I encourage you to consider the average quality of products containing sugar compared to the average quality of products containing high fructose corn syrup.

You’re welcome to join the legions of unhealthy people with poor taste, but when I grab a product off the shelf and turn it over to find high fructose corn syrup on the label, I know I’ve got a cheap, low quality product in my hand.

References

1. https://pubmed.ncbi.nlm.nih.gov/20948525/
2. https://dom-pubs.onlinelibrary.wiley.com/doi/abs/10.1111/j.1463-1326.2010.01340.x
3. https://ajcn.nutrition.org/article/S0002-9165(23)13503-9/fulltext
4. https://onlinelibrary.wiley.com/doi/full/10.1111/j.1440-1746.2009.06149.x
5. http://www.bmj.com/content/336/7639/309
6. http://www.ncbi.nlm.nih.gov/pubmed/21068145
7. http://www.mayoclinic.org/healthy-living/nutrition-and-healthy-eating/in-depth/gout-diet/art-20048524
8. https://www.acs.org/pressroom/presspacs/2007/presspac-august-22-2007.html#P61_6961
9. http://www.ncbi.nlm.nih.gov/pmc/articles/PMC2673878/
10. https://www.foodnavigator-usa.com/Article/2008/04/02/hfcs-is-not-natural-says-fda
11. https://pubmed.ncbi.nlm.nih.gov/15855169/