Folic Acid, Selected Cancers and All-cause Mortality: A Meta-analysis

Dorothy Mackerras, Joel Tan, Claire Larter
2014 International Food Risk Analysis Journal  
Fortification of foodstuffs with folic acid is mandatory in many countries. Although the effect of folic acid in reducing neural tube defects in utero is well accepted, questions have been raised about possible adverse effects of higher intakes of folic acid on adult health. An increase in colorectal cancer and some other cancers has been postulated. As part of a larger fortification monitoring program in Australia, we conducted a systematic review of trials of folic acid for these outcomes. We
more » ... these outcomes. We found 26 trials using between 0.4-20mg folic acid/day which reported all-cause mortality or the incidence of specified cancers or recurrence of colorectal adenoma. Using the in-trial follow-up data, the relative risks were 1.04 for total incident cancer (13 studies), 1.0 for colorectal and lung cancers, 0.82 for breast cancer, 1.16 for prostate cancer, 0.97 for the recurrence of colorectal adenoma and 1.11 for the recurrence of advanced colorectal adenoma. There was no association with all-cause mortality (relative risk=0.99, 23 studies). None of the relative risks were statistically significant at the customary alpha level. Our findings are similar to those of previous meta-analyses that have used different inclusion criteria to select studies.
doi:10.5772/58396 fatcat:j6v5onh5wfeyldbwzznixnwuqe