Ginger has a reputation for boosting the immune system. New results from the Leibniz Institute for Food Systems Biology at the Technical University of Munich now support this thesis. In lab tests, small amounts of a pungent component of ginger put white blood cells on high alert. The study also shows that this process involves a type of receptor that plays a role in the perception of painful heat stimuli and the sensation of pungency in food.
Whether as a medicinal plant or food, ginger is also becoming increasingly popular in Germany. According to the German Federal Statistical Office, the annual import volume of the pungent fruity root has nearly quadrupled over the past ten years to around 31,600 tons. However, even though ginger consumption has increased, the question arises whether normal consumption levels are sufficient to achieve health effects. And if so, which compounds and molecular mechanisms play a role in this.
The ginger compound enters the blood
To help clarify these questions, a team led by Veronika Somoza, director of the Leibniz Institute in Freising, Germany, conducted extensive research. The starting point was the result of an earlier pilot study, in which first author Gaby Andersen from Leibniz-LSB@TUM also played a key role. As the study shows, significant amounts of pungent compounds in ginger enter the bloodstream regarding 30-60 minutes following consuming a liter of ginger tea. By far the highest levels have been achieved by [6]-gingerol, with plasma concentrations of approximately 7 to 17 micrograms per liter.
The pungent compound is known to exert its “taste” effect via the so-called TRPV1 receptor, an ion channel on the surface of nerve cells that responds to painful heat stimuli as well as the pungent compounds in chili and ginger. Since some studies suggest that white blood cells also have this receptor, the research team tested whether [6]-gingerol influences the activity of these immune cells.
The pungent compound stimulates white blood cells
Initially, the team succeeded in detecting the receptor on neutrophil granulocytes. These cells make up regarding two-thirds of white blood cells and are used to fight off invading bacteria. Other laboratory experiments conducted by the research group also showed that even a very low concentration of almost 15 micrograms of [6]- the gingerol per liter is enough to put the cells on heightened alert. Thus, compared to the control cells, the stimulated cells reacted regarding 30% more strongly to a peptide which simulates a bacterial infection. Addition of a specific TRPV1 receptor inhibitor reversed the effect induced by [6]-gingérol.
“So, at least in experiments, very weak [6]- the concentrations of gingerol are sufficient to affect the activity of immune cells via the TRPV1 receptor. In the blood, these concentrations might theoretically be reached by consuming around a liter of ginger tea,” explains Gaby Andersen. “Thus, our results support the hypothesis that intake of common amounts of ginger may be sufficient to modulate cellular responses of the immune system. . Nevertheless, there are still many unanswered questions at the molecular, epidemiological and medical levels that need to be addressed with the help of modern food and health research,” concludes Veronika Somoza.