Diet drinks often contain a mix of sweeteners that enter the bloodstream after consumption. As the current pilot study shows, sweeteners don't just affect the taste buds.
Sweeteners are substitutes that have a very high level of sweetness but have little or no impact on energy intake. Not only in the USA, but also in Germany, they play an important role - especially for people who love sweets but want to save calories and sugar. But sweeteners don't just affect the taste buds in the mouth. Recent studies show that they also affect the human immune system, although the underlying molecular relationships are still poorly understood.

Research on sugary drinks

To find out, a pilot study was carried out. At the start of the study, participants were required to drink 10.7 mL per kilogram of body weight of a sweetener solution containing a typical drink mix of approximately 76 mg saccharin, 228 mg cyclamate and 53 mg acesulfame-K per liter. . . . Converted to a weight of 70 kg, the amount of drink was about 0.75 liters. The ingested amounts of saccharin, cyclamate and acesulfame-K corresponded to about 16, 35 and 6 percent of the permitted daily amount of sweeteners.

Later blood tests showed that blood sugar levels peaked four hours after drinking the test solution. On the other hand, the team investigated how the maximum concentrations of the individual sweeteners determined in vitro affect the white blood cells, which protect against bacteria. On the other hand, the team analyzed ex vivo immune cells taken from the subjects' blood before and after the procedure.

Reading of the affected gene

Both in vitro and in vivo, administration of sweeteners increased the expression of genes encoding taste receptors that are also normally responsive to sweeteners in the mouth. In addition, sweeteners modulate the readout profile of genes that code for proteins that regulate the immune system. According to the team, this must not lead to changes in cell functions. However, further study results showed that the modular transcription profile puts the cells in a state that makes at least isolated immune cells more sensitive to the bacterial stimulus in the presence of these three sweeteners.

A medium amount is enough. 

  "Our results show that even moderate consumption of sweeteners can have an impact on the immune cells in the blood. Of course, we can't say at the moment whether this is good or bad for our health. This requires further research. However, our findings may lead to the hypothesis that taste receptors do not function in response to dietary stimuli. As a sensor not only in the mouth, but also in immune cells, explains food biologist Dietmar Krautwurst.