The researchers of the University of Bonn (Germany) discovered that when they fed the mice a diet rich in salt, the animals developed much more serious bacterial infections than when the diet was not rich in salt.
The same thing happened with humans: when people added six grams more From salt a day to her usual daily intake, her immune cells were significantly less effective in fighting bacteria. This additional salt intake is roughly equivalent to two quick meals.
“Mice on a diet rich in salt suffered from kidney infections exacerbated by E.coli or systemic infections by Listeria monocytogenes due to reduced ability of neutrophils – a type of leukocytes – to kill ingested bacteria. In addition, Neutrophils from healthy volunteers were less able to control bacteria after consuming a high-salt diet. Since the typical Western diet is packed with salt, these findings reveal that people may be becoming more vulnerable to bacterial infections, “they highlight. Katarzyna Jobin, Natascha E. Stumpf, Sebastian Schwab and others in their study.
The main function of neutrophils it is ingesting foreign cells, in particular bacteria, since otherwise infections can progress and worsen. Scientists demonstrated this in mice infected with listeria – bacteria that are present in contaminated food and that trigger fever and sepsis.
“In the spleen and liver of these animals, we locate between 100 and 1,000 times the number of disease-causing pathogens [comparando con los que consumían menos sal]”Katarzyna Jobin, lead author of the study, clarifies. The researchers found that urinary tract infections in these mice also took much longer to heal.
The researchers were surprised by the findings, as previous research had suggested otherwise. For example, animals with certain parasitic infections of the skin they eliminate them much more quickly once they start consuming a diet rich in salt. Macrophages – the large cells that target and ingest parasites – become more active in a saline environment. But apparently, it is only valid for skin infections and not for internal organs.
The World Health Organization (WHO) advises that the maximum intake of salt per day is not higher than five grams, which is equivalent to about a full teaspoon.