Fruit juice an effective infection preventative - Israeli doctor finds cranberry and blueberry juices effective in prevention of urinary tract infections

Nutrition Health Review, Summer, 1991

Tel Aviv, Israel: Researchers in Israel have confirmed that cranberry juice can help prevent urinary tract infection.

The fact has been known for many years, but the reasons for fruit juice's effect have not been clear. Scientists have speculated that a high content of vitamin C could be responsible. Others supposed that juice's high acidic content provided protection. Vitamin C is a strong factor, but other ingredients may also be beneficial.

The new research evaluated seven juices to observe whether they contained compounds that could prevent bacteria from adhering to the wall of the urinary tract, thereby causing infection. In surprising revelations, cranberry and blueberry juices contained such substances. Grapefruit, guava, mango, orange and pineapple juices did not.

The experiments, conducted by Dr. Nathan Sharon, a biochemist at Weizmann Institute of Science, and colleagues, implicated the bacteria Escherichia coli (also known as E. coli bacteria) to be the problem and they are convinced that particular juice can wash them out with urination. The fruit juices are not capable of killing the bacteria, Dr. Sharon acknowledges.

It is an unidentified substance, present in cranberry and blueberry juices, the researchers say, that seems to be a potent inhibitor of bacteria clinging to cell walls. Vitamin C has also proved to be successful in treatment, other practitioners have reported.