Normally, corn syrup isn't very sweet. But once its glucose has been converted into fructose and the corn syrup has been transformed into high-fructose corn syrup, it's very sweet, sweeter than sugar. HFCS also mixes better with other liquids -- it's much easier to mix high-fructose corn syrup into soft drinks than sugar, for example. Best yet, despite the considerably more complicated processing, high-fructose corn syrup is cheaper to use than regular sugar. Additionally, the sugars in the syrups act as a preservative, which is why HFCS is now added to some meats.
So where is all the corn coming from? Throughout the past century, the U.S. government has supported its farmers through subsidies to ensure that the United States' domestic food production continued to grow. Growers of corn, in particular, have been rewarded for producing more and more corn, regardless of whether the excess could be put to use. As a result, the United States grows and consumes more corn than any other nation on earth [source: Corn Refiners Association].
Improvements in the ability to process HFCS were welcome news to the corn industry and the soft drink industry -- the former had a new outlet for its stock, and the latter could save hundreds of millions of dollars by switching to HFCS from the slightly more expensive sugar. The Midwest was literally covered with the raw materials, and soon more than a dozen large HFCS processing plants sprang up in the region to handle the growing demand for the sweetener.
In 1970, more than 83 percent of sweetener consumed in the United States was sucrose. By 1997, that number had dropped to 43 percent, and the rest of the sweetener being consumed -- about 57 percent -- was HFCS [source: OU Kosher].
The problem with this change in consumption is that studies have shown that when people consume artificial sweeteners, they have an increased desire to continue eating [source: Tordoff]. This occurs with all sweeteners, and it doesn't seem related to the way the body metabolizes the sweetener, but rather the taste of sweetness.
In a study of 1,400 middle school students, it was found that nearly one-third of their caloric intake was added sugars (as opposed to the sugars found naturally in fruits and vegetables, which aren't normally counted when discussing sugar intake) [source: Havel]. In 2005, Americans each consumed, on average, more than 42 pounds (19 kilograms) of high-fructose corn syrup [source: Corn Refiners Association]. The average American also consumes 200 daily calories from HFCS, which is close to 10 percent of all daily calories consumed.
Obesity rates have been climbing in the United States since the 1980s [source: CDC]. In 2007, Colorado was the only state with less than 20 percent of its population qualifying as obese. Additionally, between 1994 and 2004, new diagnoses of type-2 diabetes increased by 23 percent [source: Gardner]. Many people believe that HFCS plays some role in the obesity and diabetes epidemics now plaguing the United States and much of the world. We'll take a look at how HFCS may play a role in these unhealthy trends in the next section.