When people restrict their salt intake for a period of time, they come to prefer a lower amount their previous "normal" intake seems too salty. A recent study investigated whether the same is true for sugar consumption. If so, a period of sugar restriction might result in a preference for less sweet foods and might be a means of reducing food intake.
Writing in the American Journal of Clinical Nutrition, Dr. Paul M. Wise of the Monell Chemical Senses Center, Philadelphia, PA and collaborators tested this possibility in a five-month study of 33 healthy men and women, aged 21-54 years. All reported typically consuming at least two sugar- or corn syrup-sweetened drinks per day. Specifically, the investigators examined whether a lower sugar intake would affect participants' perception of sweet taste intensity and pleasantness.
The participants all consumed their normal diets for the first month of the study. Then, 16 were assigned to the experimental group, and the rest continued their usual diets. Those in the experimental group were instructed to reduce their intake of sugar calories by 40 percent for months 2-to-4 of the study; they kept diet records which were monitored by the researchers. During the fifth month, all participants were allowed to eat any diet they wished.
During the last two weeks of each month of the study the participants were presented with a set of vanilla puddings and raspberry drinks of varying sweetness. They rated these with respect to perceived sweetness. By the second month of sugar reduction, those in the low-sugar group rated low-sugar concentration food and drinks as sweeter than did the control group. But by the end of the fifth month, this difference was no longer apparent.
As for perceived pleasantness of the various degrees of sweetness, this didn't differ between groups across the months of the study. So the reduction in dietary sugar didn't seem to play a lasting role in the participants' preferences. This, the authors suggest, argues against the idea that alterations in perceived sweetness might affect eating behavior.
As they also suggest, much more research must be conducted to confirm these finding this should only be considered a preliminary finding given the small number of participants. Further, the reliance of self-reported dietary information is another weakness of the current study.