How do cranberries prevent urinary tract infection?
Researchers from Worcester Polytechnic Institute, in Massachusetts went into the lab to seek the answer.
First, the details.
- Atomic force microscopy was used to study the adhesion forces between Escherichia coli and a model surface (silicon nitride).
- The objective was to determine the effect of cranberry products to change the ability of bacterial to adhere to the surface.
- Bacteria were grown in tryptic soy broth supplemented with either light cranberry juice cocktail or cranberry proanthocyanidins (PACs; have antioxidant properties).
And, the results.
- Longer exposure of the bacteria to either the cranberry juice or the PACs resulted in a greater decrease in bacterial attachment to the surface.
The bottom line?
Assuming that silicon nitride is appropriate for this research, the results indicate that chemicals present in cranberries — and not the acidity of cranberry juice, as previously thought — prevent infection-causing bacteria from attaching to the cells that line the urinary tract.
Studies in patients supporting the use of cranberries are summarized here, here, here, and here.
3/12/09 20:56 JR