Despite recent efforts by the corn industry to rehabilitate its image, high fructose corn syrup (HFCS) remains a controversial product with questionable effects on health. Several studies have suggested a link between its consumption and the onset of diseases such as Type 2 diabetes and obesity. In addition, experiments with mice have demonstrated that a diet rich in fructose and low in copper can trigger serious liver damage in the test subjects.
High fructose corn syrup is made from a natural ingredient, cornstarch, but the process which converts it into the finished product is decidedly not natural. Three different chemical processes are necessary in order to first convert the cornstarch into a fructose/glucose blend and then to artificially change the ratio of fructose and glucose. Between the two forms of sugar, fructose, especially when atomically unbound from glucose, is considered to be the more hazardous to overall health. Finished high fructose corn syrup is 55% fructose, 45% glucose.
The problem with fructose is that unlike glucose or sucrose, it proceeds directly to the liver during the digestive process. The liver converts excess fructose into fat for storage, completely bypassing the normal insulin response from the pancreas which would ordinarily help control blood sugar levels. The result is an increased level of fructose sugar, converted to fat by the liver, but no corresponding feeling of fullness triggered by a sensitivity to insulin. Regular sugar or sucrose may contain more calories than HFCS, but its effect on blood sugar levels is more manageable.
This is not to suggest that all fructose is unhealthy. Indeed, many fruits contain a natural form of fructose which the body can assimilate. These fruits also contain fiber and other healthy nutrients, an argument which cannot be made for high fructose corn syrup. In fact, some studies suggest that the chemical composition of HFCS causes it to leech vital minerals out of body tissue in order to stabilize itself atomically.
The very existence of high fructose corn syrup as an alternative to natural sucrose or sugar is controversial in its own right. Many consumer products sold in the United States and other countries before the 1980s used sucrose or natural sugar as a sweetener. Government tariffs on imported sugar during the 1980s gave domestic corn growers the opportunity to tout the new corn-based sweetener. It was cheaper to produce than sucrose sugar, and was not subject to high import taxes. Thus, many manufacturers made the switch in order to save money.
Eventually food manufacturers began adding high fructose corn syrup to products which didn't even have a need for sweeteners. Because the syrup made products more stable on store shelves and American consumers demonstrated a preference for sweetened products, manufacturers have been using it in everything from ketchup to "natural" fruit juices which already contained fructose and glucose. It has become nearly impossible to avoid consuming some form of it when using commercially developed food products today.
Although there are commercial food products available which use sucrose or other natural sweeteners, the high import taxes on sugar still exist and the corn industry has powerful lobbyists which encourage lawmakers to continue their support for domestically grown corn products. HFCS is considered by some to be a hazardous, unnatural product which has the potential to harm consumers through higher incidents of obesity, diabetes and liver disease.