Is Fructose the Problem?

Table sugar (sucrose) is a combination of two simple sugars, glucose and fructose. Robert Lustig suggested that obesity is in particular a response to fructose, which he proposed is readily converted to fat in the liver. This theory is evaluated. In particular, in the United States, the replacing sucrose with high-fructose corn syrup in sugar-sweetened, drinks drew attention to fructose. However, in practice there is little difference in the level of fructose that comes from table sugar or corn syrup. With the doses of fructose that are normally consumed, very little is converted to fat. There is consistent evidence that fructose is similar to other sugars in that it increases body fat only to the extent it provides additional calories. Lustig also suggests that the glucose provided by sucrose stimulates the release of insulin, which results in the production of fat. However, sucrose increases blood glucose to a lesser extent than many other foods, as such, there is no reason to believe that fructose has a particular role in obesity, other than providing calories.