Feasibility of dietary folic acid reduction intervention for men on active surveillance for prostate cancer

Fortification of the US food supply has increased folic acid intake and resulted in a concomitant decrease in neural tube defects in women. However, a body evidence supports the hypothesis that increased circulating folate levels due to excessive dietary or supplemental folic acid may be harmful for men with prostate cancer. Therefore, this pilot study aimed to investigate the feasibility of a reduced folic acid dietary intervention in men on an active surveillance monitoring program for prostate cancer. Men with low-grade prostate cancer enrolled into a 12-week dietary folic acid reduction diet. Primary outcome was red blood cell (RBC) folate reduction at 12 weeks. Other outcomes include serum folate, homocysteine, and vitamin B12 levels. The number of patients who complete the trial and reasons for disenrollment or dropout were also assessed. Twenty-eight participants were enrolled into the dietary intervention study. Six participants withdrew from the study and a total of 21 participants completed all baseline and week 12 biochemical assessments. Only 18 participants completed all dietary questionnaires. Participants withdrew from the study due to difficulty with the diet or personal reasons. A substantial reduction was noted in serum folate (p