Fructose, a sugar found in many foods and beverages, may make you more likely to overeat. A small, preliminary study has found that a meal with a lot of fructose in it may leave you still feeling hungry as compared to a meal with a lot of glucose in it.
Fructose is a simple carbohydrate, and is found naturally in fruits, but is also in high-fructose corn syrup, the main sweetener found in a lot of processed foods and drinks. Glucose is the sugar that is produced in the body by the natural breakdown of complex carbohydrates. Apparently, fructose does not suppress the areas of the brain that control appetite as well as glucose does, which may leave you feeling hungry even though you have eaten.
High-fructose corn syrup also contains glucose. Table sugar is sucrose, a different sugar.
Researchers at the Keck School of Medicine at the University of Southern California in Los Angeles asked 24 men and women to take part in an experiment. They were asked to drink either a beverage sweetened with glucose or one sweetened with fructose. They were then asked to look at images of various foods and say how hungry they were. While they looked at the images, the participants were hooked up to a functional magnetic resonance imaging scanner that was used to track the activity in an area of the brain that is known to be a "reward" center.
The participants who drank the fructose drink said they experienced a greater degree of hunger when looking at the pictures of food then those who drank glucose. The fructose drink also provoked a greater response in the "reward" center, which the researchers interpreted to mean the participants had a greater desire to eat.
This is a small study and more work is needed before big conclusions can be made about sweeteners in food and how they affect hunger. However, this finding is consistent with other research that has shown that fructose does not trigger the same changes in insulin levels in the blood that glucose triggers.
The study was presented at the annual meeting of the American College of Neuropsychopharmacology, but it has not been published in a peer-reviewed medical journal as yet.