High fructose corn syrup–myth versus science
Like monosodium glutamate (MSG), the additive that everyone avoids, except there is absolutely no evidence that it does anything to anyone, high fructose corn syrup (HFCS) has evolved to become the current pariah of the food industry. Even the name sounds a bit chemical, with that “high fructose” leading you to believe it has to be bad. But is it?
That’s where we need to look at the science, because the answers to the questions are quite complicated and quite simple.
Hey, before we start, what are sugars?
Before we can even start talking about HFCS, we need to really talk about sugars. So, what exactly is a sugar? For most people, it’s the white stuff on the table, and according to everything we hear today, it should be avoided. However, like most things, sugar is much more complicated than that.
There are two broad types of sugars, aldose and ketose, along with over twenty individual, naturally-found sugars, called monosaccharides. Of all of those sugars, only four play any significant role in human nutrition: glucose, fructose, galactose, and ribose (which has a very minor nutritional role, though a major one as the backbone of DNA and RNA). Got that? Four sugars.
But it gets a bit more complicated. Many sugars form disaccharides that are compounds made of two monosaccharides covalently bound together. Table sugar, the white stuff in our sugar bowls, is sucrose that is a one molecule of glucose bound to one molecule of fructose. Sucrose is also the main sugar in most other commercially purchased sugars that you find including brown sugar, molasses, beet sugar, and maple sugar (and syrup). Milk sugar is lactose, which is glucose and galactose, maltose is two glucose molecules, and there are a few dozen less common ones. Each has a slightly different taste, and some rare ones provide unique tastes to certain fruits and vegetables.
But we get to make this even more complicated. Starches are also sugars. They are just long chains, or polymers, of individuals sugars, almost always glucose. Cellulose, which is a major component of paper, wood, natural plant fibers, and many other items, are glucose polymers. So are insect shells. Sugar is a major part of our lives.
Before we can continue onto our discuss about HFCS you need to know one important thing. Humans can only absorb monosaccharides like glucose, fructose, galactose and ribose. In other words, all of those disaccharides and polysaccharides must be broken down into the constituent monosaccharide before it has any usefulness for a human. The gut has a variety of different enzymes that break down these starches and disaccharides–so sucrose cannot be absorbed, but it is broken down by sucrase into glucose and fructose, then absorbed. By the way, any disaccharide or polysaccharide that isn’t broken down remain in the gut, providing food for our gut bacteria, thereby maintaining a healthy digestive system.
There is one more important thing to note about these sugars, which will be important as we move along with this story. Fructose is 1.73 times more sweet than sucrose despite having the same exact caloric content. So technically, you could use about 58% less fructose than sucrose to get the same sweetness. You’re probably seeing where this is going, but stay tuned.
What is high fructose corn syrup?
HFCS consists of 24% water, and the rest fructose and glucose. There are two main types of HFCS, HFCS 55 (used mostly in soft drinks) which is approximately 55% fructose and 42% glucose; and HFCS 42 (used in other types of beverages and processed foods), which is approximately 42% fructose and 53% glucose. There is another type, HFCS-90, approximately 90% fructose and 10% glucose, which is used in small quantities for specialty applications (interestingly, low calorie drinks, because, for the same sweetness about 33% less calories are added), but it is primarily blended with HFCS 42 to make HFCS 55.
Well before the advent of HFCS, in the 1950′s, candy and soft drink manufacturers utilized “invert sugar” by exposing sucrose to a weak acid solution, then recrystallizing which dissociated the covalent bond between the glucose and fructose, and exposing the fructose molecule, which, of course, is so sweet, that it made the overall effect to be much more sweet with the same amount of sugar. This allowed the manufacturers of the candy and sodas to get more sweetness with less sugar, saving a lot of money. So, “high fructose” has been around since the 1950′s, exploiting the greater sweetness of fructose even before HFCS was available.
So, why was HFCS developed?
First, corn syrup is much cheaper than sucrose (table sugar), but it’s not as sweet because it has a higher glucose to fructose ratio than sucrose (and as we mentioned, fructose is very sweet). Second, it retained moisture better than sucrose (twice as many molecules). Third, it was available in a liquid form and didn’t caramelize as readily as sucrose (this last one could be an advantage or a disadvantage, depending on the use).
But here’s the most important point: HFCS allowed soda manufacturers to use less sugar — and thus fewer calories — in their products without reducing its sweetness. Using sucrose, sugar from cane or beets, would require 20% more sugar (along with 20% more sugar calories) than using HFCS 55.
But natural sugars are better!!!
So how does HFCS compare to natural sugar products that we believe are better for you? Well, other than that naturalistic fallacy, which claims that natural is better somehow, most naturally sweet products are very similar to HFCS in fructose content:
- Honey: about 17% water, with almost all the remainder being sugars. The main sugars are fructose 38%, glucose 31%, maltose 7%, sucrose 1.3%, other sugars 1.5%. In other words, honey could be considered a “high fructose” type of sweetener.
- Maple syrup: about 60% sugar, with that sugar being 95% sucrose, 4% glucose and 1% fructose.
- Apples: over 10% sugar, 57% fructose, 23% glucose and 20% sucrose. Very high fructose.
- Peaches: 8.4% sugar, 57% sucrose, 23% glucose and 18% fructose.
- Pears: 9.8% sugar, 64% fructose, 28% glucose and 8% sucrose.
- Grapes: 15% sugar, with the sugars being 53% fructose and 47% glucose.
In other words, some of these “natural” foods have as high, or, in the case of apples, peaches and pears, even higher levels of fructose than HFCS. Remember, fructose is fructose. There is no chemical difference between the fructose created by plants or created by corn. It’s the same exact fructose molecule. The body thinks it’s the same. The body metabolizes it in the same way.
OK, I’m convinced. But is fructose bad for you?
Now the answer gets much more complicated. Remember, because the food manufacturers are using less HFCS to get the same sweetness as sucrose, the amount of fructose consumed between a drink that contains just sucrose and one that contains just HFCS (and has the same sweetness level) is almost the same. In other words, you’re getting the same amount of taste (because of the fructose), less calories, and the same amount of fructose. So your worries shouldn’t be about the fructose.
Moreover, strong scientific meta-reviews of clinical research have established that there is little evidence of links between increased fructose intake and any deleterious health effects:
- Health implications of fructose consumption: A review of recent data–”A moderate dose (≤ 50g/day) of added fructose has no deleterious effect on fasting and postprandial triglycerides, glucose control and insulin resistance. There is no existing evidence for a relation between moderate fructose consumption and hypertension. Fructose may induce hyperuricaemia, but mainly in patients with gout.” In other words, eating moderate amounts of fructose have no ill-effects. The issue remains that if you eat too much fructose (and any other sugar), there are deleterious metabolic effects, and that should be the major issue.
- Evidence-based review on the effect of normal dietary consumption of fructose on development of hyperlipidemia and obesity in healthy, normal weight individuals–” The results of the analysis indicate that fructose does not cause biologically relevant changes in TG (triglycerides) or body weight when consumed at levels approaching 95th percentile estimates of intake.
- Metabolic effects of fructose and the worldwide increase in obesity–”There is, however, no unequivocal evidence that fructose intake at moderate doses is directly related with adverse metabolic effects. There has also been much concern that consumption of free fructose, as provided in high fructose corn syrup, may cause more adverse effects than consumption of fructose consumed with sucrose. There is, however, no direct evidence for more serious metabolic consequences of high fructose corn syrup versus sucrose consumption.”
So, let’s review. Fructose is just a monosaccharide that is metabolized by the body. It is sweeter than other mono- and disaccharides, so less is needed, a lot less. HFCS is just a natural corn syrup with a higher fructose to glucose ratio to make it taste sweeter, so less is needed for the same sweetness. Most naturally sweet products also have high fructose contents, hence their high sweet tastes. And from scientific reviews, there is no evidence that fructose has any effect on obesity or metabolic disease beyond what is expected from the consumption of any other sugar.
Therefore, you shouldn’t be eating sugars and sticking with whole grain foods to prevent type 2 diabetes. Oh wait, there’s no proof.
One last thing. What’s with this blaming everything for excess weight? HFCS isn’t at fault, but it sure is easy to blame instead of yourself.
Key citations
- Dolan LC, Potter SM, Burdock GA. Evidence-based review on the effect of normal dietary consumption of fructose on development of hyperlipidemia and obesity in healthy, normal weight individuals. Crit Rev Food Sci Nutr. 2010 Jan;50(1):53-84. Review. PubMed PMID: 20047139.
- Rizkalla SW. Health implications of fructose consumption: A review of recent data. Nutr Metab (Lond). 2010 Nov 4;7:82. PubMed PMID: 21050460; PubMed Central PMCID: PMC2991323.
- Tappy L, Lê KA. Metabolic effects of fructose and the worldwide increase in obesity. Physiol Rev. 2010 Jan;90(1):23-46. Review. PubMed PMID: 20086073.
A calorie is not a calorie.
http://eatingacademy.com/nutrition/do-calories-matter
If Dr. Attia wants to state that there is a different way to look at calories, then my suggestion would be that he research it in a controlled manner, then support his "alternative hypothesis" with several publications in high impact factor, peer-reviewed journals. Until such time, he's giving me an opinion, which on the scale of real science, ranks right at the bottom along with anecdotes. In other words, it has no meaning whatsoever.
Just accidentally came across your blog- I like it. The reason I have tried to stay away from high fructose corn syrup is because of the concern of mercury contamination when it is produced.
[...] additives are one of the most passionate issues amongst people who eat (which would be everyone). High fructose corn syrup. Salt. Sugar. Trans fats. Polysorbate 80. Some of the angst caused by these additives is that they [...]
[...] first, what is high fructose corn syrup? I wrote about HFCS a few weeks ago, debunking some of the myths about HFCS with real [...]
The last sentence is kind of misleading. You’re trying to bring up another topic, regarding whole grain foods and diabetes in order to link to another article, but you also include “you shouldn’t be eating sugars” as part of the sentence, and it sounds like you’re suggesting that reduction of sugars isn’t related to prevention of type 2 diabetes.
Well, the short answer is that the reduction of sugars may not necessarily lead to the prevention of type 2 diabetes, since the cause is genetic, metabolic, and/or lifestyle. So, maybe consuming too much sugar leads to weight gain which may lead to a metabolic disease which may lead to type 2 diabetes. But it does not necessarily lead to it. I do not adhere to non-scientific diet myths, and the anti-sugar myth is one of them.
The human physiology is amazingly adept at dealing with environmental stressors with regards to food. The implication that there is a “ideal” diet has been thoroughly debunked. My most recent article went at that, describing both anthropological and primate proxy evidence. Simply put, calories inputed that exceed calories expended will cause weight gain. Excessive weight is a potential cause of type 2 diabetes (with other risk factors).
We blame sugars consumption for a lot of craziness based on anecdotes. But the problem is not the sugars, but the excess food consumption with no burning of that energy. So, yeah, it wasn’t misleading. It was making a point about food myths, which I guess will be investigated further at a later date. I guess I need to debunk some Type 2 diabetes myths.
I agree regarding your statement that we can’t attribute weight gain or diabetes to any particular nutrient, and that to effectively lose weight, the focus needs to be on reducing net calories (primarily because the scientific evidence says so, but I also have myself as an anecdote as I’ve lost one hundred pounds over the last two years without focusing on any specific nutrient).
However, I was taking issue with the last sentence because it didn’t seem related to the article, because your article was focused not on the idea that sugar leads to health problems, but with the idea that there is something wrong with sugars that have particular compositions. I don’t really like sarcasm in general (even more so on the internet because it can be especially hard to detect), but I think the last sentence would fit the article better if you said “Therefore, you should avoid high fructose corn syrup, and also, stick with whole grain foods to prevent type 2 diabetes. Oh wait, there’s no proof.”
Perhaps I’m nitpicking. In general, I enjoyed reading your article. I’ll make sure to send people to it next time I see them casually assuming that HFCS is more unhealthy than other forms of sugar.
Valid point, and probably a necessary clarification. I try to refrain from sarcasm (but it’s hard), though snark I consider to be useful at time. However, you still did give me an idea about cleaning up some of the myths about Type 2 diabetes. I personally stay away from sugars because there are better food sources. Read my other article about what apes eat. One hundred odd different plants. And a lot of figs.
The last sentence is kind of misleading. You're trying to bring up another topic, regarding whole grain foods and diabetes in order to link to another article, but you also include "you shouldn't be eating sugars" as part of the sentence, and it sounds like you're suggesting that reduction of sugars isn't related to prevention of type 2 diabetes.
Well, the short answer is that the reduction of sugars may not necessarily lead to the prevention of type 2 diabetes, since the cause is genetic, metabolic, and/or lifestyle. So, maybe consuming too much sugar leads to weight gain which may lead to a metabolic disease which may lead to type 2 diabetes. But it does not necessarily lead to it. I do not adhere to non-scientific diet myths, and the anti-sugar myth is one of them.
The human physiology is amazingly adept at dealing with environmental stressors with regards to food. The implication that there is a "ideal" diet has been thoroughly debunked. My most recent article went at that, describing both anthropological and primate proxy evidence. Simply put, calories inputed that exceed calories expended will cause weight gain. Excessive weight is a potential cause of type 2 diabetes (with other risk factors).
We blame sugars consumption for a lot of craziness based on anecdotes. But the problem is not the sugars, but the excess food consumption with no burning of that energy. So, yeah, it wasn't misleading. It was making a point about food myths, which I guess will be investigated further at a later date. I guess I need to debunk some Type 2 diabetes myths.
I agree regarding your statement that we can't attribute weight gain or diabetes to any particular nutrient, and that to effectively lose weight, the focus needs to be on reducing net calories (primarily because the scientific evidence says so, but I also have myself as an anecdote as I've lost one hundred pounds over the last two years without focusing on any specific nutrient).
However, I was taking issue with the last sentence because it didn't seem related to the article, because your article was focused not on the idea that sugar leads to health problems, but with the idea that there is something wrong with sugars that have particular compositions. I don't really like sarcasm in general (even more so on the internet because it can be especially hard to detect), but I think the last sentence would fit the article better if you said "Therefore, you should avoid high fructose corn syrup, and also, stick with whole grain foods to prevent type 2 diabetes. Oh wait, there's no proof."
Perhaps I'm nitpicking. In general, I enjoyed reading your article. I'll make sure to send people to it next time I see them casually assuming that HFCS is more unhealthy than other forms of sugar.
Valid point, and probably a necessary clarification. I try to refrain from sarcasm (but it's hard), though snark I consider to be useful at time. However, you still did give me an idea about cleaning up some of the myths about Type 2 diabetes. I personally stay away from sugars because there are better food sources. Read my other article about what apes eat. One hundred odd different plants. And a lot of figs.
Also, I’m guessing you base your approach to this high-fructose corn syrup “fallacy” on the idea of “innocent until proven guilty.” Problem is, like many, you misunderstand the concept.
Well, you didn’t read it, so how would you know. And of course, making an ad hominem attack is usually a method reserved with those who lack evidence.
Heh. I notice you didn’t reply to the bit about MSG. I also notice YOU replied to my “ad hominem attack” with an ad hominem attack.
The bit about MSG made me feel you had a pro-industry axe to grind here. Either that or you fancied yourself a daring contrarian, out to prove the idiot “common knowledge” about MSG and HFCS wrong. Either way, eh.
Why am I going to read a long article when the author makes an out-of-the-blue misstatement in the very first paragraph?
If you want to be read, write better.
More ad hominem attacks. My out of the blue statement was based on another article that I wrote about MSG. Once again, logical fallacies, such as ad hominem attacks, or strawman “industry axe” arguments, are reserved by those who lack any evidence for their statements. I have utilized tons of scientific evidence that HFCS and MSG are just myths invented by people who lack scientific understanding of chemistry and metabolism.
Looks like you got a live one Hank.
No, his pseudoscientific silliness was dead on arrival.
Ahem. I quit reading in the first paragraph, because there IS evidence MSG does stuff to people. Speaking just for myself, MSG gives me a dull, persistent headache.
Actually, I’ve also seen studies that corn syrup is much worse for you than real sugar.
MSG is simply glutamic acid, a simple amino acid, which has no effect on the body except to be metabolized into proteins. Amusing how people make stuff up out of nothing, but that’s why we use science to understand these things, as opposed to inventing ideas out of nothing. And as we say, post hoc ergo propter hoc.
Mindy K. Howie If you read over some of my other blog posts, you have to weed out early primary research from the much better meta-reviews which take data from several studies and determine which are high quality and which are not. I quoted only the meta-reviews, which clearly demonstrate that nothing is going on. Fructose is fructose, there is no difference. Sugar is sugar. Eat too many calories, however derived, will cause obesity. The early studies, which probably are the ones you remember, didn’t try to separate what was caused by fructose or by sugars in general. Better studies have begun to understand that.
In fact, some studies show that fructose has a lower glycemic effect, which might reduce an insulin response making it the better sugar. See how these things work? Sometimes the story is quite a bit more complex, and depending on how you define the question the answer might actually be good or bad. I avoid excess sugars period, whether it’s honey, HFCS, white sugars, or whatever. It’s not because one or the other is better or worse, it’s just because there are better and more tasteful calories out there. Like potato chips.
If you’re going to go all righteous about ad hominem attacks, I’m sorry to tell you you’re going to have to refrain from making them yourself.
You keep using that word. I don’t think it means what you think it means.
Also, I'm guessing you base your approach to this high-fructose corn syrup "fallacy" on the idea of "innocent until proven guilty." Problem is, like many, you misunderstand the concept.
Well, you didn't read it, so how would you know. And of course, making an ad hominem attack is usually a method reserved with those who lack evidence.
Heh. I notice you didn't reply to the bit about MSG. I also notice YOU replied to my "ad hominem attack" with an ad hominem attack.
The bit about MSG made me feel you had a pro-industry axe to grind here. Either that or you fancied yourself a daring contrarian, out to prove the idiot "common knowledge" about MSG and HFCS wrong. Either way, eh.
Why am I going to read a long article when the author makes an out-of-the-blue misstatement in the very first paragraph?
If you want to be read, write better.
More ad hominem attacks. My out of the blue statement was based on another article that I wrote about MSG. Once again, logical fallacies, such as ad hominem attacks, or strawman "industry axe" arguments, are reserved by those who lack any evidence for their statements. I have utilized tons of scientific evidence that HFCS and MSG are just myths invented by people who lack scientific understanding of chemistry and metabolism.
Looks like you got a live one Hank.
No, his pseudoscientific silliness was dead on arrival.
Ahem. I quit reading in the first paragraph, because there IS evidence MSG does stuff to people. Speaking just for myself, MSG gives me a dull, persistent headache.
Actually, I've also seen studies that corn syrup is much worse for you than real sugar.
MSG is simply glutamic acid, a simple amino acid, which has no effect on the body except to be metabolized into proteins. Amusing how people make stuff up out of nothing, but that's why we use science to understand these things, as opposed to inventing ideas out of nothing. And as we say, post hoc ergo propter hoc.
Mindy K. Howie If you read over some of my other blog posts, you have to weed out early primary research from the much better meta-reviews which take data from several studies and determine which are high quality and which are not. I quoted only the meta-reviews, which clearly demonstrate that nothing is going on. Fructose is fructose, there is no difference. Sugar is sugar. Eat too many calories, however derived, will cause obesity. The early studies, which probably are the ones you remember, didn't try to separate what was caused by fructose or by sugars in general. Better studies have begun to understand that.
In fact, some studies show that fructose has a lower glycemic effect, which might reduce an insulin response making it the better sugar. See how these things work? Sometimes the story is quite a bit more complex, and depending on how you define the question the answer might actually be good or bad. I avoid excess sugars period, whether it's honey, HFCS, white sugars, or whatever. It's not because one or the other is better or worse, it's just because there are better and more tasteful calories out there. Like potato chips.
If you're going to go all righteous about ad hominem attacks, I'm sorry to tell you you're going to have to refrain from making them yourself.
You keep using that word. I don't think it means what you think it means.