Although fortifying food with folate as a public health measure reduces the number of children born with spina bifida, new research from Chile suggests that it may also increase the risk of bowel cancer.
"Our data provide new evidence that a folate fortification program could be associated with an additional risk of colon cancer," Dr. Sandra Hirsch said in a statement.
Hirsch and her colleagues at the University of Chile, Santiago, assessed the number of people hospitalized with colon cancer before and after a folate fortification program was implemented in Chile in January 2000. The program added 220 micrograms of folic acid to every 100 grams of wheat flour.
Compared with the 1992-1996 period, the number of patients with colon cancer during the 2001-2004 period was 2.61-fold higher in people 45 to 64 years of age and 2.90-times greater in those 65 to 79 years, the investigators report in the European Journal of Gastroenterology and Hepatology.
For the most part, little change was seen in the occurrence of other diseases before and after folate fortification. The one exception was breast cancer, which appeared to occur twice as often during the period after fortification. However, the research team thinks that this may have been due to the implementation of programs designed to detect and treat breast cancer at an early stage.
Further research, the authors conclude, is needed to determine the amount of folate that prevents neural tube defects like spina bifida, but does not increase the risk of colon cancer or any other adverse events.