Is the power of the mind enough to change how our bodies react to what we eat? Last month, researchers uncovered a psychological phenomenon in which people actually altered their own immediate blood glucose level after drinking a soft drink with labels purposely misrepresenting the sugar contents.
Without the help of accurate nutrition labels, thirty Type 2 diabetics put their perception to the test. The volunteers checked into a laboratory for 2 separate parts of the experiment with a three day break in between. Each visit, they drank a beverage that was labeled differently than its actual caloric content. As diabetics, the volunteers already had a heightened awareness of paying attention the sugar content on labels.
The drinks were completely identical to one another, however, and each contained 62 g of sugar. The trick labels were either labeled as 0 g of sugar or 124 g of sugar. To help equalize the timing of the blood sugar responses, the volunteers had to drink all of the beverage in 3 minutes. Starting 20 minutes later, their blood glucose levels were measured, along with questionnaires about how sugary the beverage tasted to them and if they would consume it again.
The blood sugar values matched what they believed they had consumed—with higher blood glucose readings after drinking the label claiming to contain 124 g of sugar, and lower blood glucose readings after drinking what was labeled as 0 g of sugar. Remember, though, all of the drinks were the same!
This is far from being a solution to controlling blood sugar, but the researchers are hoping that they can learn more about why we perceive and attribute values to foods and how it can be manipulated for nutritional counseling.
Their current hypothesis for this phenomenon is that the drink label itself caused an indirect pathway to occur which was dependent on the nutritional satisfaction that they gained from reading the label. In accordance, another indirect pathway occurs when the drink label stimulated a perceived sugar content which then affected nutritional satisfaction. They found that it wasn’t the perception of the sugar level which caused changes in the glucose levels, but the feelings associated with the sugar level.
Another hypothesis is that diabetics who focus on external cues for eating such as scheduled times, or at times when other people have meals, exhibit a stronger reaction to other external stimuli (the nutritional labels in this case). Diabetics who focus more on internal cues, such as hunger, may be less likely to experience this effect.
Park, C., Pagnini, F. & Langer, E. Glucose metabolism responds to perceived sugar intake more than actual sugar intake. Sci Rep 10, 15633 (2020). https://doi.org/10.1038/s41598-020-72501-w