Cruciferous Vegetables and Estrogen Detoxification

Dr. Leah Hassall, ND

We all know that eating broccoli is healthy, I mean our parents were always telling us to eat it when we were kids right? Well it turns out that broccoli and other cruciferous vegetables (cauliflower, collard greens, Brussel sprouts, cabbage and kale) are not only healthy because they are chock-full of antioxidants and fiber, but they are also potent hormone detoxifiers.

Estrogen and progesterone work in a woman’s body in a delicate balance. When the scales tip towards more estrogen relative to progesterone, we often see heavy menstrual bleeding, acne, more PMS symptoms (cramping, breast tenderness, moodiness, low mood), spotting between periods and fertility concerns. As women approach menopause, the hormone scales tend to tip even more towards estrogen. Because of this, they may often experience very heavy bleeding.

One way to support the liver’s detoxification of estrogens is indol-3-carbinol (I3C). I3C (and its parent chemical DIM) is found in relatively high amounts of cruciferous vegetables. I3C works by promoting the conversion of stronger estrogens into weaker/less active estrogen, increasing efficient estrogen metabolism, preventing estrogens from building-up in the body and reducing free-radical production. In studies, I3C has been shown to have great promise as a potential helpful addition to the treatment and prevention of estrogen-sensitive cancers like breast, ovarian and uterine cancer. I3C has also been shown to have an anti-inflammatory and anti-tumor role in the liver itself! In case you were wondering, I3C is also beneficial in men – in fact, the Journal of Nutrition (Oxford), has stated that there is “ample evidence for the benefit of I3C and DIM for the prevention and treatment of prostate cancer”.

In addition to helping to detoxify estrogen metabolites through the liver, naturopathic physicians work to improve detoxification of hormones through other organs of elimination including the gastrointestinal tract and kidneys. As a side note, freshly ground flaxseed is one of the best ways to help bind and eliminate estrogens in the intestines. In fact, the Society of Obstetricians and Gynaecologists of Canada(SOGC) recommend it for the first-line treatment of fibrocystic/tender breasts, a common sign of excess estrogen. NDs will often use blood, salivary and/or urinary hormone testing to determine which hormones may be imbalanced and which organs of elimination may need some assistance. I3C is just one of the many tools that naturopathic physicians use to bring back the balance in your hormones.


  1. Aggarwal, B.B., Ichikawa, H. 2005. Molecular targets and anticancer potential of indole-3-carbinol and its derivatives. Cell Cycle. 4(9):1201-15.
  2. Auborn, K.J., Fan, S., Rosen, E.M., Goodwin, L., Chandraskaren, A., Williams, D.E., Chen, D., Carter, T.H. 2003. Indole-3-carbinol is a negative regulator of estrogen. J Nutr.133:2470S-2475S.
  3. Bradlow, H.L, Michnovicz, J., Telang, N.T, Osborne, M.P. 1991. Effects of dietary indole-3-carbinol on estradiol metabolism and spontaneous mammary tumors in mice. Carcinogenesis. 12(9):1571-4.
  4. Michnovicz, J.J., Adlercreutz, H., Bradlow, H.L. 1997. Changes in levels of urinary estrogen metabolites after oral indole-3-carbinol treatment in humans. J Natl Cancer Inst. 89(10):718-23.
  5. Rogan, E.G. 2006. The natural chemopreventive compound indole-3-carbinol: state of the science. In Vivo. 20(2):221-8.
  6. Sarkar, F., Li, Y. 2004. Indole-3-Carbinol and Prostate Cancer. The Journal of Nutrition134(12): 3493S–3498S.