Flaws in Duke University statement about high fructose corn syrup

An 18 March 2010 press release, titled High Fructose Corn Syrup Linked to Liver Scarring, issued by Duke University, incorrectly singled out high fructose corn syrup as being responsible for scarring in the liver and other liver diseases, when the underlying study for the release reviewed dietary intake of fructose-containing beverages - not high fructose corn syrup.

In the study Increased Fructose Consumption is Associated with Fibrosis Severity in Patients with Non-alcoholic Fatty Liver Disease, researchers asked patients who were already diagnosed with non-alcoholic fatty liver disease (NAFLD) to recall how many fructose-containing beverages they consumed over the prior year. Although the researchers acknowledged that beverages containing fructose accounted for only 50% of total dietary intake of fructose - leaving out other important dietary sources of fructose such as fruits and vegetables - they nevertheless elected to base the findings of the recall study on beverages sources only. Magnifying these problems with their data interpretation still further, the researchers counted intake of fruit juices and other beverages containing fructose from sugar, even though those beverages contain no high fructose corn syrup at all.

It should be noted that fructose has not been proven to be a cause of NAFLD in humans, and NAFLD subjects are compromised individuals with significant health problems which have very little to do with fructose intake. Moreover, associative studies of this kind are widely judged to be of low scientific value when trying to establish cause and effect, data from studies like this that are dependent on recollection of the study subjects are notoriously imprecise, and these studies are full of confounding variables and exceedingly difficult to control.

This study unnecessarily confuses consumers about the impact of dietary fructose. Fructose is safe and is commonly found in fruits, vegetables, fruit juices, table sugar, honey, high fructose corn syrup and maple syrup.