Professor Jolanta Prywer and her team from the Institute of Physics of the Łódz University of Technology found out that phosphoric acid contained in some non-alcoholic carbonated drinks, especially cola, may cause faster growth of urinary stone layers in people who already have a stone unrelated to a bacterial infection in their urinary tract, the scienceinpoland.pl website wrote.
This is due to the fact that the kidney stone surface is usually porous and promotes the adhesion of bacteria, which can become centres of subsequent urinary stone layers.
Phosphoric acid is used in soda to give it a sour taste and as a preservative.
Kidney stone disease, also known as urolithiasis, affects 1 to 20 percent of the population, and manifests when a solid piece of material develops in the urinary tract, according to scienceinpoland.pl.
There has been a strong increase in the incidence of infectious urolithiasis in recent years, especially in highly developed countries, Prywer was quoted as saying by the website.
Kidney (or urinary) stones typically form in the kidney and leave the body in the urine stream.
A small stone may pass without causing symptoms. If a stone grows to more than 5 millimeters (0.2 inches), it can cause blockage of the ureter, resulting in sharp and severe pain in the lower back or abdomen as well as other afflictive symptoms.
Source: scienceinpoland.pl; Wikipedia