Indole-3-carbinol (I3C) is a phytochemical derived in high concentrations from the Brassica family of vegetables, including broccoli, cauliflower, Brussels sprouts, and cabbage. I3C and its derivative compounds have been shown to exert anticancer mechanisms in the human body. I3C has been shown to exhibit direct antiestrogenic activity via competitive inhibition of estrogen receptors; upregulate the cytochrome P450 isoenzymes CYP1A1, CYP1A2, and CYP1B1, thereby increasing estrogen metabolism; shift estrogen metabolism away from the more proliferative (16‑OHE1) towards the more protective (2‑OHE1) estrogen species; induce cancer cell apoptosis via NF‑κB pathways; inhibit cancer cell growth at the G1 stage; and increase the expression of p21, p27 and p53 tumor suppressors. The use of I3C for the prevention and treatment of breast, endometrial, colon, and prostate cancers as well as for the treatment of herpes simplex virus (HSV) and human papillomavirus (HPV), including cervical dysplasia and cervical cancer, has been studied in depth in both animals and humans with favourable results.