Drinking cranberry juice is a common home remedy for a urinary tract infection, but just how it works was not understood.
A group of researchers believe they have found the answer: The effect is due not to the highly acidic nature of cranberries but to specific compounds in cranberries that inhibit the adherence of Escherichia coli (bacteria) to uroepithelial cells.
Escherichia coli, or E. coli, is a bacterium found normally in the digestive tract. However, if certain strains of the bacteria gain access to the normally sterile environment of the bladder and urinary tract, the bacteria can trigger an infection, with symptoms including a frequent, painful urge to urinate and blood in the urine.
The condition can be readily treated with antibiotics, but recurs in 25% of cases.
In a new study, the researchers tested the ability of cranberry extracts to inhibit the binding of certain, disease-causing strains of E. coli to cells taken from the lining of the urinary tract which would promote flushing of bacteria from the bladder into the urine stream, resulting in the prevention or reduction of symptoms.
This binding process is thought to be an early step in the initiation of an infection. During the course of the 5-year study, the team found that extracts containing compounds called "condensed tannins" or "proanthocyanidins," which are found in cranberries and blueberries, could inhibit the binding process.
The New England Journal of Medicine October 8,1998;339:1085-1086.
Dr. Mercola's Comment:
The study was funded by Ocean Spray Cranberries, Inc. Clearly there was a bias in this research. However, it is interesting to note that the researchers also found these same proanthocyanidins in blueberries. Dr. Jonathon Wright has long explained that cranberries work by the process described above.
However, his studies showed that the beneficial agent was D-mannose. This is the first I am aware of the proanthocyanidins being given the credit. Clinically, there is no question that cranberries work. I would, however, not recommend the juice as there is far too much fructose which is a simple sugar that will not protect against urinary tract infections but promote poor colon health (see above study).
I recommend you try D-mannose instead. A pure, high-quality form has recently become commercially available as a natural supplement and you can get it now in our store. Non-toxic and safe, ClearTract D-Mannose:
Supports a healthy urinary tract
Is 10- 50 times stronger than cranberry!
Produces rapid action in as little as 24-48 hours
Does not kill friendly bacteria
Is safe for long term use -- neutral pH
Is 100% all natural D-Mannose and nothing else
D-mannose actually adheres to the receptors on the lining of the bladder that attach to the bacteria. This forces the bacteria to slide right off and into the toilet. I advise taking Clear Tract D-Mannose once or twice a day as a far superior, more effective, and less damaging alternative to cranberry juice for the prevention of chronic UTIs.
Also, I would be most interested in hearing from anyone who is willing to share their experiences using blueberries as a treatment mode.