There is a clear link between taking antibiotics and an increased risk of developing colon cancer within the next five to ten years. This has been confirmed by researchers at Umeå University, Sweden, after a study of 40,000 cancer cases. The impact of antibiotics on the intestinal microbiome is thought to lie behind the increased risk of cancer.
“The results underline the fact that there are many reasons to be restrictive with antibiotics. While in many cases antibiotic therapy is necessary and saves lives, in the event of less serious ailments that can be expected to heal anyway, caution should be exercised. Above all to prevent bacteria from developing resistance but, as this study shows, also because antibiotics may increase the risk of future colon cancer.”
Researchers found that both women and men who took antibiotics for over six months ran a 17 per cent greater risk of developing cancer in the ascending colon, the first part of the colon to be reached by food after the small intestine, than those who were not prescribed any antibiotics.
However, no increased risk was found for cancer in the descending colon. Nor was there an increased risk of rectal cancer in men taking antibiotics, while women taking antibiotics had a slightly reduced incidence of rectal cancer.
The increased risk of colon cancer was visible already five to ten years after taking antibiotics. Although the increase in risk was greatest for those taking most antibiotics, it was also possible to observe an admittedly small, but statistically significant, increase in the risk of cancer after a single course of antibiotics.