Diindolylmethane (3,3′-diindolylmethane or DIM) is a compound derived from chemical breakdown of indole-3-carbinol. It can be found in cruciferous vegetables most notably in broccoli, cabbage, cauliflower and kale. Some scientist believe that these vegetables may offer protection against some cancers due to their diindolylmethane content .
Diindolylmethane and estrogen metabolism
According to National Cancer Institute : “Diindolylmethane promotes beneficial estrogen metabolism in both sexes by reducing the levels of 16-hydroxy estrogen metabolites (“bad estrogens”) and increasing the formation of 2-hydroxy estrogen metabolites (“good estrogens”), resulting in increased antioxidant activity.” Animal studies have shown that diindolylmethane alters estrogen metabolism and inhibits carcinogen-induced mammary tumor growth . Tumor growth is depressed because diindolylmethane can influence the activity of estrogen receptor (group of proteins found inside cells activated by the hormone estrogen) either directly or indirectly . Study by Sanderson and others  was the first to demonstrate the ability of diindolylmethane to decreased aromatase activities in vitro. Some studies have reported that diindolylmethane competitively binds to the AhR (Aryl Hydrocarbon receptor) [4,5] and blocks the effects of estrogens via inhibitory Ah receptor-estrogen receptor cross-talk . Ichen and colleagues  observed in vitro antiestrogenic responses for DIM and confirmed that compound elicits AhR-mediated antiestrogenic responses.
Because it is relatively new to the area of research not many research is available. The data is mainly preliminary and done in animals or in vitro. Because of its effect on estrogen metabolism it is an interesting supplement in cancer-fight especially in hormone dependent cancers which can be fueled by excess hormone exposure. Also, due to the poor bioavailability of diindolylmethane, its use as a supplement has been limited .
Diindolylmethane as a weight loss supplement
Although diindolylmethane is claimed to facilitate weight loss by targeting release and metabolism of stored fat there’s no scientific evidence to support this.
Diindolylmethane side effects
Long-term exposure to diindolylmethane produces no observable toxicity, a study in rats reports . According to RxList.com : “Diindolylmethane is safe when consumed in the small amounts found in foods. There isn’t enough information to know if supplements containing diindolylmethane are safe.”
- National Cancer Institute. 3,3′-diindoylmethane Retrieved from at 4. May 2013
- Sanderson, J. Thomas, et al. “2, 3, 7, 8-Tetrachlorodibenzo-p-dioxin and diindolylmethanes differentially induce cytochrome P450 1A1, 1B1, and 19 in H295R human adrenocortical carcinoma cells.” Toxicological sciences 61.1 (2001): 40-48.
- Kim, Young S., and J. A. Milner. “Targets for indole-3-carbinol in cancer prevention.” The Journal of nutritional biochemistry 16.2 (2005): 65-73.
- Jellinck, Peter H., et al. “Ah receptor binding properties of indole carbinols and induction of hepatic estradiol hydroxylation.” Biochemical pharmacology 45.5 (1993): 1129-1136.
Bjeldanes, Leonard F., et al. “Aromatic hydrocarbon responsiveness-receptor agonists generated from indole-3-carbinol in vitro and in vivo: comparisons with 2, 3, 7, 8-tetrachlorodibenzo-p-dioxin.” Proceedings of the National Academy of Sciences 88.21 (1991): 9543-9547.
Chen, Ichen, et al. “Aryl hydrocarbon receptor-mediated antiestrogenic and antitumorigenic activity of diindolylmethane.” Carcinogenesis 19.9 (1998): 1631-1639.
- Dr. Oz. “Diindolylmethane (DIM): Is This Right for You?” Retrieved from http://blog.doctoroz.com/ at 4. May 2013
- RxList The internet drug index. Retrieved from http://www.rxlist.com/ at 4. May 2013
- Find a Vitamin or Supplement. Retrieved from WebMD.com at 6. May 2013
Leibelt, Dustin A., et al. “Evaluation of chronic dietary exposure to indole-3-carbinol and absorption-enhanced 3, 3′-diindolylmethane in Sprague-Dawley rats.” Toxicological Sciences 74.1 (2003): 10-21.