From the February 18, 2004 issue of the Journal of the American Medical Association, (JAMA) comes an alarming study that suggests that breast cancer is linked to the use of antibiotics. Researchers pored over the medical records of thousands of American women and found that those who took the drugs most often had twice the risk of the disease.
Dr. John D. Potter, director of the division of public health sciences at the Fred Hutchinson Cancer Research Center in Seattle and an author of the report noted, "This is potentially worrisome, but we don't know why this connection exists, we only have an observation." He went on to qualify his findings by saying, "At the moment, we need to see these results replicated with more research before drawing any conclusions."
This was not the only study on this phenomenon as in 2000, scientists in Finland found that women younger than 50 who had taken antibiotics for urinary tract infections also had an elevated risk for getting cancer.
The original JAMA study ended with a compelling conclusion, "Use of antibiotics is associated with increased risk of incident and fatal breast cancer. It cannot be determined from this study whether antibiotic use is causally related to breast cancer, or whether indication for use, overall weakened immune function, or other factors are pertinent underlying exposures. Although further studies are needed, these findings reinforce the need for prudent long-term use of antibiotics."