Corn syrup myths

There are a lot of myths out there about high fructose corn syrup. While there are plenty of reasons to avoid consuming too much corn syrup (and all sugars), that’s no reason to spread rumors.

Have any commonly held beliefs about corn that you’d like to know more about? Let us know in the comments.

Myth: Huge amounts of the sizable US corn crop go to HFCS production. Here’s an example that sums up this idea from Grist: “The Big Corn People began to grow so much royally-subsidized GMO corn that they turned it into millions of gallons of high fructose corn syrup.”

It’s true, a portion of the US corn crop is used for HFCS production. It’s also true that corn syrup is cheap because the corn industry receives subsidies. But there’s a lot more to this story.

How is corn used?

Most of the US corn crop is used for animal feed. In 2006-2007, 5.6 billion bushels of corn were used for animal feed, 2.1 billion for exports, 2.1 billion for ethanol, 753 million for corn sweeteners, 272 million for corn starch, 190 million for corn foods (tortillas, cereal, etc), and 137 for alcoholic beverages, according to Iowa State University’s High Fructose Corn Syrup – How sweet it is (pdf).

It’s more than a little dishonest to blame the monocultures on HFCS, when so much of the crop is used for feed. Again, that’s 5.6 billion bushels of corn for animal feed versus 753 million bushels for sweeteners in 2007. We might also take a second look at ethanol.

Corn is used for so many things because it can be separated into fractions fairly easily. According to that same ISU Factsheet, a single bushel of corn (about 60 lbs) produces three primary products after wet milling:

  • 1.6 lbs corn oil
  • 13.5 lbs corn protein gluten animal feed
  • 2.6 lbs corn gluten meal used for poultry feed, pre-emergent herbicide, and fur cleaner.

The remaining starch can then be used to produce one of three alternatives:

  • 33 pounds of corn sweetener
  • 32 pounds of cornstarch
  • 2.5 to 2.7 gallons of ethanol or beverage alcohol

In other words, a bushel of corn can be used to make animal feed and either corn syrup or ethanol – not both. Over the years, the percentage of the crop that’s gone for sweetener or ethanol has changed a great deal. According to Table 27  – US use of field corn, by crop year (.xls), in 1991 7% of the corn crop was used to make sweetener, and 6.10% was used to make alcohol. In 2009, 5.78% of the corn crop was used for sweetener, while 35.82% was used for ethanol. Over the same years, the amount of corn harvested increased, so total corn syrup production did increase, but not much compared to ethanol.

If you’re looking to blame something for corn monocultures, it makes sense to turn first to animal products and then to ethanol… not to corn syrup.

How much does it cost?

Corn syrup is cheaper than sugar because of the climate in the US, tariffs on imported sugar, and because of corn subsidies. Sugar can be refined from two crops: sugar cane and sugar beets. Sugar cane is a tropical crop, and there aren’t many places in the US where it can be grown (see this map of US sugar cane acres in 2007 from the USDA to see just how few places). Sugar beets aren’t grown in many places in the US either (see this map of US sugar beet acres in 2007). Sugar cane and sugar beets both produce about 50% of US sugar, according to University of Florida Extension’s Overview of Florida Sugarcane.

Since there isn’t much sugar produced in the US, and due to the climate in the US we couldn’t produce much more even if we wanted to, we would need to import it from Brazil, India, or Europe. That could be a problem for locavores looking for sugar, but it’s definitely a problem for US sugar producers who want to stay competitive with producers overseas. Sugar producers have been successful in lobbying for high tariffs, so we don’t import much sugar. I don’t understand all the tariffs and other programs, but you can learn more at the USDA Foreign Agricultural Service’s US Sugar Import Program.

Since we can’t and don’t produce much sugar in the US, and there are trade barriers to importing sugars, it makes sense for food producers to look for an alternative sweetener. We have excellent climate and soils for corn (see this map of US corn acres in 2007), and it’s not that difficult to make sugar from corn starch.

More questions

I have to wonder if, in the absence of trade barriers, we would still have more corn syrup than corn sugar. Similarly, how much would the balance of sweeteners actually change if corn subsidies were removed? Since such a small amount of the crop is used to produce all the sweetener we need, I wonder if things would change much at all.

Finally, even if we had enough sugar to meet consumer demand for sweet processed foods, would Americans actually consume any less total sugar than we do now? I think it wouldn’t change at all. As for what might change consumption of total sugars, we might consider subsidies on healthy (or at least healthier) foods and/or a tax on unhealthy foods and sodas. Here’s hoping.


  1. Something I’ve never really had the energy to look into – I’ve heard that HFCS has a higher glycemic index than bog standard regular sugar – is this true, and does it even matter?
    Also – in the same vein – I note that India (or some of India) are getting excited recently about the prospect of utilizing HFCS over sugar to cater to the increasingly sweet tooth (If you’ve ever eaten an authentic Indian dessert you’d be shocked to think they could get any more sweet toothed…) of the consumers there.
    Hurrah for tales soon to come of exactly 1500 cattle dying after eating GM corn residue!

  2. I have heard that about glycemic index, and I hope to get to the bottom of that soon. Or, even better, I wonder if I can recruit a nutrition friend to guest post. Hm…
    I wonder if corn is a good choice of sweetener India or not. I mean, if they are already growing sugar cane with success, then it seems silly to switch. Karl and I were just talking today about the need for a Life Cycle Analysis for different sweeteners to see which ones are the least environmentally harmful (of course, it would vary by region and country, but at least something would help).

  3. If I remember right, and I probably don’t, the excitement generated was due to the somewhat lower cost per unit than for cane sugar – from what I recall India is a net importer of sugar for use in the food industry, and the import tariffs make it a little cheaper.
    Cane may take a little more work than corn also – I believe I read that somewhere (possibly the same article), and as there is no Bt, or roundup ready cane etc, that could be another reason.

  4. I also wrote a post about HFCS on my personal blog:
    If I understand the difference in glycemic index correctly, HFCS is higher in its glycemic index because the sugars are already mono-saccharides and will readily get absorbed. But the context of what food it is contained in will also alter this index. HFCS in bread may not be absorbed so easily, while HFCS in soda may be absorbed more quickly. Whether the small difference in this index between HFCS and sugar matters much for health remains to be seen. Moreover, while the disaccharide sucrose may be added to the food, if it is acidic you may find those sucrose molecules hydrolyzing into glucose and fructose anyway – raising the glycemic index to that of HFCS. It only takes weak acids to do that, like in fruit juice.
    Watch the total simple sugar content, not what sugar it is! – That’s my non-expert sweetener advice.
    Sugar is an interesting thing. While being a basic metabolite, and once central to many economies, it is back again with current sweetener politics and ethanol for fuel. It seems to me that people get so worked up about it because of its dual role in deliciousness and chubbiness. Love to hate.

  5. My spouse is taking a course on international economics and he learned that the candy industry has a deal with the sugar producers and the US government that exempts them from sugar tariffs. They only covered this briefly in class, so he doesn’t have many details. Anyone know about this? Do any other food manufacturers (is that the right word?) get this exemption, or just the candy manufacturers? How does this affect the cost of sugar vs corn syrup?

  6. A fitness blog-buddy of mine is all over this– He says HFCS isnt different from table sugar, and referenced this nice review… dang it… *wanders off and tries to find review*

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