I've read that Folic acid would not be desirable to take when on 5-FU (which is the primary drug within Folfox). This is because it might potentiate the effect of 5-FU beyond what is desired. So if your oncologist hasn't recommended that you take Folate, you should inform him before taking it. When I was on chemo, I was advised to avoid the anti-oxident supplements. After chemo was complete, I began taking Vit D, Calcium & Aspirin at the recommendation of my oncologist.
Stage 3 R/C -1 node+ ( 7/09)
5 wks radiation, 2 wks chemo: 5FU (8-9/09)
Rectal surgery: tumor removal (11/09)
10 rounds Xeloda: 3000mg/daily 1 wk on/1 wk off (1/10-6/10)
Supplements: Aspirin, Calcium, Vit. D3
03/27/17: 7+ yrs. since surgery--still NED