Indole 3 Carbinol I3C supplement health benefit
Anti cancer benefit, review of research studies
February 7 2018 by Ray Sahelian, M.D.

Benefit and side effects, review
Indole-3-carbinol is found in cabbage, cauliflower, and Brussels sprouts along with other vegetables and spices, for instance cardamom. Indole-3-carbinol is converted in the gut to diindolylmethane (DIM). When an indole 3 carbinol supplement is ingested, there is little or no indole 3 carbinol found in the bloodstream. The substance that is found in the bloodstream after taking an indole 3 carbinol supplement is DIM, Diindolylmethane.

buy Indole-3-Carbinol (I3C) 200 mg, 60 Vcaps
Indole-3-Carbinol, 200 mg, 60 CapsulesIndole-3-Carbinol is a naturally occurring phytochemical found in cruciferous vegetables such as cabbage, broccoli, and kale. NOW I3C provides powerful antioxidant protection, helping to prevent cellular damage caused by free radicals. In addition I3C can help to maintain healthy hormonal balance for both men and women and therefore may support the health of the breast, prostate, and other reproductive organs. I3C is also known to support the liver's detoxification processes as well as normal cellular reproduction. LinumLife provides the highest level of Flax Lignans available, which are also beneficial in supporting healthy hormonal balance.*


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Buy Indole-3-Carbinol, 200 mg, 60 Capsules

Supplement Facts
Serving Size: 1 Capsule
Serving Per Bottle: 60 Vegetable Capsules
  Amount Per Capsule % DV
200 mg
Daily Value or Recommended not established.

Supplement Facts: Indole-3-Carbinol (I3C) 200 mg
LinumLife Complex 200 mg (Flax Seed Lignan Extract) (Linum usitatissimum) (Seed Coat) {yields min. 10 mg as SDG (Secoisolariciresinol Diglucoside)} 

Suggested Usage: As a dietary supplement, take 1 capsules 1 or 2 times daily, preferably with meals. For long term use have approval by your physician.

Side effects, safety
I have not seen any studies regarding long term adverse reactions. One morning I took 4 pills and did not have any negative reactions.

Benefit of this nutrient

Effect of indole 3 carbinol supplement ingestion
A phase I study of indole-3-carbinol in women: tolerability and effects.
Cancer Epidemiology Biomarkers Prev. 2005.
We completed a phase I trial of indole-3-carbinol (I3C) in 17 women (1 postmenopausal and 16 premenopausal) from a high-risk breast cancer cohort. Subjects ingested 400 mg I3C daily for 4 weeks followed by a 4-week period of 800 mg I3C daily. Serum estradiol, progesterone, luteinizing hormone, follicle-stimulating hormone, and sex hormone binding globulin showed no significant changes. Comparing the results from the placebo and the 800 mg daily dose period, CYP1A2 was elevated by I3C in 94% of the subjects. Lymphocyte glutathione S-transferase activity was increased in response to I3C. The maximal increase was observed with the 400 mg daily dose of I3C, with no further increase found at 800 mg daily. If the ratio of hydroxylated estrone metabolites is a biomarker for chemoprevention, as suggested, then 400 mg I3C daily will elicit a maximal protective effect.

Blood thinner
indole-3-carbinol is a potent antithrombotic agent with antiplatelet activity. It has its blood thinning effect through the inhibition of GP IIb/IIIa receptor and thromboxane B(2) formation. Until more studies are published, it may be a good idea to not take Coumadin (or warfarin) with a I3C supplement.

Cancer treatment or prevention

Prevention and treatment of cancer with indole-3-carbinol.
Altern Med Rev. 2001. Seattle Cancer Treatment and Wellness Center, Kirkland, WA
Indole-3-carbinol is a naturally occurring constituent of many plant foods. Oral administration of indole-3-carbinol has been shown to manipulate estrogen metabolism in humans in a possibly beneficial manner. indole-3-carbinol increases the 2/16-hydroxyestrone ratio, a ratio found to be predictive of breast cancer risk in some prospective studies. Animal and in vitro studies have identified a number of other possibly beneficial effects of indole-3-carbinol and its metabolites, including inhibition of estrogen binding and modulation of oncogene expression. A chemopreventive effect of indole-3-carbinol has been demonstrated in a number of animal models. Some chemical carcinogenesis models have found a tumor promoting effect of indole-3-carbinol, however. Epidemiological studies support the hypothesis that high intakes of indole-3-carbinol may have broad chemopreventive effect. Preliminary human trials have demonstrated that indole-3-carbinol is well tolerated and has a sustained estrogen modifying effect. indole-3-carbinol is a good candidate for clinical trial in women at increased risk of developing breast cancer.

Breast cancer
The repair protein, regulated by genes called BRCA1 and BRCA2, is important for preventing damaged genetic information being passed on to the next generation of cells. If people have a faulty BRCA gene they are at a higher risk of developing some forms of cancer, including breast, ovarian and prostate cancer. Low amounts of the BRCA proteins are seen in cancer cells, so the scientists propose higher levels might prevent cancer developing. Researchers suggest the ability of indole-3-carbinol to boost the amount of BRCA proteins could explain its protective effects.

A novel mechanism of indole-3-carbinol effects on breast carcinogenesis involves induction of Cdc25A degradation. Capital Normal University, Beijing, China. Cancer Prev Res (Phila Pa). 2010.

Cell Cycle. 2014. Indole-3-carbinol and its N-alkoxy derivatives preferentially target ERα-positive breast cancer cells.

Indole-3-carbinol is a negative regulator of estrogen.
J Nutr. 2003. North Shore-Long Island Jewish Research Institute, Manhasset, NY
Dietary indole-3-carbinol prevents the development of estrogen-enhanced cancers including breast, endometrial and cervical cancers. =Whereas estrogen increases the growth and survival of tumors. Our long-range goal is to best use indole-3-carbinol together with other nutrients to achieve maximum benefits for cancer prevention. This study examines the possibility that induction of growth arrest in response to DNA damage (GADD) in genes by diindolylmethane (DIM), which is the acid-catalyzed condensation product of indole-3-carbinol, promotes metabolically stressed cancer cells to undergo apoptosis. We evaluated whether genistein, which is the major isoflavonoid in soy, would alter the ability of indole-3-carbinol/DIM to cause apoptosis and decrease expression driven by the estrogen receptor (ER)-alpha. Expression of GADD was evaluated by real-time reverse transcription-polymerase chain reaction. We show a synergistic effect of indole-3-carbinol and genistein for induction of GADD expression, thus increasing apoptosis, and for decrease of expression driven by ER-alpha. Because of the synergistic effect of indole-3-carbinol and genistein, the potential exists for prophylactic or therapeutic efficacy of lower concentrations of each phytochemical when used in combination.

Q. I have read on your site and various others that there is great promise in Indole 3 Carbinol / DIM in terms of breast cancer prevention. Would you consider the use of this supplement as effective for preventing a recurrence of breast cancer, for example, DCIS? Further, if DCIS were removed with clear margins in a wide local excision, do you think that this supplement could possibly replace the standard follow up treatment of radiation or mastectomy? Or would it just complement such conventional treatments?
   A. DCIS, ductal carcinoma In situ, is not an invasive breast cancer. It stays inside the milk duct of the breast in which it started. I could not find human research with indole 3 carbinol in relation to DCIS to know the answers to these questions. It is possible that I3C could complement traditional breast cancer chemotherapy but I have no solid evidence to base this on.

Q. I was diagnosed with breast cancer 3 years ago, went trough chemotherapy then surgeries to removed the shrunk lump. Now, after a small and painful fracture on my pelvic bone the oncologist found several metastasis in my bones (spine and pelvic). As a treatment I have been prescribed Letrazole to reduce the oestrogen in my body (this cancer is hormone-dependent). I have done my research and found that Letrazole can be effective but will decrease my bone density on the long term. I'm 49 and I am prescribed that medication for the rest of my life. I do not want to have my bone density decreased since I am already vulnerable because of the fracture and several lesions in my bones (spine and pelvic) therefore I did some research and found that Indole-3-Carbinol (I3C), a product that we find in cruciferous vegetables, can do the exact same thing than Letrazole, but without the side effects. I bought supplement of Indole-3-Carbinol and have started to take 200 mg twice a day about 4 days ago. At the same time I have started just 3 days ago on the Letrazole, because I was not totally sure about the Indole-3-Carbinol and I wanted to be on the 'safe side`. Any thought on that? I really need your point of view since I am not taking Letrazole pills with a smile, knowing what the long term effect will be.
   A. Unfortunately not enough research is available to know how effective I3C is in these cases.

Q. I have been using Indole 3 carbinol for 7 yrs for stage 3B breast cancer. I'm a former Gerson Therapy patient; No chemo / radiation / tamoxifen! Is it okay to use broccoli sprouts extract product with Indole 3 Carbinol?
   A. I have not come across studies with the combination, therefore it is not easy to predict any benefits or interactions.

Cervical cancer
Q. Wondering if you could provide information on the safety of using Indole-3-carbinol after the diagnosis of Stage 1 cervical cancer. I see all of the literature / research on its preventative properties. I have had surgery as well as chemo and still face the possibility of recurring tumor. Is it safe to use in this situation?
   A. I have not seen research regarding the use of indole-3-carbinol as a preventive measure or treatment supplement for cervical cancer at this time.

Testimonial received 2018
I have been using this product for about a month now for hpv / cervical dysplasia and so far has seen an immediate improvement in my skin. What would happen if I take it with food? Sometimes on an empty stomach I get too revved up and experience tremors. Also, would three times a week still be effective?
   A. You may consider taking it just before eating or with food. Not enough research is available to know the ideal dosage and frequency of use.

Tumour Biol. 2015. Indole-3-carbinol suppresses NF-κB activity and stimulates the p53 pathway in pre-B acute lymphoblastic leukemia cells. B cell precursor acute lymphoblastic leukemia (BCP-ALL) is the most common type of cancer in children. Dramatic improvements in primary therapy for childhood ALL have led to an overall cure rate of 80 %, providing opportunities for innovative combined-modality strategies that would increase cure rates while reducing the toxic side effects of current intensive regimens. In this study, we report that indole-3-carbinol (I3C), a natural phytochemical found in cruciferous vegetables, had anti-leukemic properties in BCP-ALL NALM-6 cells. Our results indicated that using nontoxic agents, such as I3C, in combination with anthracyclines might provide a new insight into the development of novel combination therapies in childhood BCP-ALL.

Lymphoma and leukemia
Anti-adult T-cell leukemia / lymphoma effects of indole-3-carbinol.
Retrovirology. 2009; University of the Ryukyus, Nishihara, Okinawa, Japan.
Adult T-cell leukemia / lymphoma (ATLL) is a malignancy derived from T cells infected with human T-cell leukemia virus type 1 (HTLV-1), and it is known to be resistant to standard anticancer therapies. Indole-3-carbinol (I3C), a naturally occurring component of Brassica vegetables such as cabbage, broccoli and Brussels sprout, is a promising chemopreventive agent as it is reported to possess antimutagenic, antitumorigenic and antiestrogenic properties in experimental studies. The aim of this study was to determine the potential anti-ATLL effects of I3C both in vitro and in vivo. Our preclinical data suggest that I3C could be potentially a useful chemotherapeutic agent for patients with Adult T-cell leukemia / lymphoma.

Liver cancer
Biochim Biophys Acta. 2015. Indole-3-carbinol inhibits tumorigenicity of hepatocellular carcinoma cells via suppression of microRNA-21 and upregulation of phosphatase and tensin homolog.

Curr Drug Metab. 2016. Indole-3-Carbinol I3C and its Major Derivatives: Their Pharmacokinetics and Important Roles in Hepatic Protection. Indoles, including indole-3-carbinol I3C and its derivatives, are the products of glucosinolate hydrolysis catalyzed by the enzyme myrosinase. Under acidic conditions, I3C polymerizes into 3, 3- diindolylmethane DIM. Recently, I3C and its dimer DIM have shown protective effects on chronic liver injuries, including viral hepatitis, hepatic steatosis, liver cirrhosis, and liver cancer. Indoles, especially I3C and DIM as phytochemicals, exert anti-fibrosis, anti-tumor, anti-oxidant, immunomodulatory, detoxification and anti-inflammation effects on hepatic protection through pleiotropic mechanism.

Lung cancer
Carcinogenesis. 2015. Combinations of indole-3-carbinol and silibinin suppress inflammation-driven mouse lung tumorigenesis by modulating critical cell cycle regulators.

Prostate cancer
Indole 3 Carbinol may play a role in prostate cancer. It may also play a role in breast cancer.

Indole-3-carbinol (I3C) exhibits inhibitory and preventive effects on prostate tumors in mice.
Food Chem Toxicol. 2007.
This study was designed to investigate the effect of indole-3-carbinol (I3C) in cell lines and on prostate cancer tumor growth in mice when given as a therapeutic and as a preventive treatment. I3C, injected intraperitonially significantly inhibited the tumor growth and affected the angiogenesis process by decreasing the microvessel density and complexity. I3C has a significant inhibitory effect on prostate cancer cells in vitro and in vivo, and offers a potential usage as both preventive and therapeutic agent for humans.

Indole-3-carbinol and prostate cancer.
J Nutr. 2004.. Karmanos Cancer Institute, Wayne State University School of Medicine, Detroit, MI
Our studies have shown that indole-3-carbinol, a common phytochemical in cruciferous vegetables, and its in vivo dimeric product 3,3'-diindolylmethane (DIM) upregulate the expression of phase I and phase II enzymes, suggesting increased capacity for detoxification and inhibition of carcinogens. Indole-3-carbinol can induce G1 cell-cycle arrest and apoptosis in prostate cancer cells. Indole-3-carbinol and DIM regulate many genes that are important for the control of cell cycle, cell proliferation, signal transduction, and other cellular processes, suggesting their pleiotropic effects on prostate cancer cells. We recently found that indole 3 carbinol functions as an inhibitor of Akt and nuclear factor kappaB (NF-kappaB), which play important roles in cell survival and which are believed to be potential targets in cancer therapy. Studies have already shown that the inactivation of Akt and NF-kappaB is responsible for chemosensitization of chemoresistant cancer cells. Because there is no effective treatment strategy for hormone-dependent and, most importantly, hormone-independent and metastatic prostate cancer, our strategies to sensitize prostate cancer cells to a chemotherapeutic agent by indole-3-carbinol and DIM is a novel breakthrough that could be used for devising novel therapies for prostate cancer.

PLoS One. 2013. Indole-3-Carbinol Inhibits Nasopharyngeal Carcinoma Growth through Cell Cycle ArrestIn Vivo and In Vitro. Nasopharyngeal carcinoma is a common malignant tumor in the head and neck. Because of frequent recurrence and distant metastasis which are the main causes of death, better treatment is needed. Indole-3-carbinol (I3C), a natural phytochemical found in the vegetables of the cruciferous family, shows anticancer effect through various signal pathways. I3C induces G1 arrest in NPC cell line with downregulation of cell cycle-related proteins, such as CDK4, CDK6, cyclin D1 and pRb. In vivo, nude mice receiving I3C protectively or therapeutically exhibited smaller tumors than control group after they were inoculated with nasopharyngeal carcinoma cells.

Vulvar intraepithelial neoplasia
A randomized phase II trial of indole-3-carbinol in the treatment of vulvar intraepithelial neoplasia.
Int J Gynecol Cancer. 2006. Queen Elizabeth Hospital, Sheriff Hill, Gateshead, United Kingdom.
The aim of this study was to determine the potential therapeutic benefits of indole-3-carbinol (I3C) in the management of vulvar intraepithelial neoplasia. Women with histologically confirmed high-grade VIN were randomized to receive 200 and 400 mg/day of I3C. There was a significant improvement in symptomatology with the introduction of I3C. Lesion size and severity were also significantly reduced. However, tissue biopsy from the worst-affected vulval areas revealed no improvement in grade of VIN during the 6-month period,. There were no significant differences in results between those women taking 200 mg/day and those on 400 mg/day. This study has shown significant clinical improvement in symptomatology and vulvoscopic appearance of VIN with I3C therapy.

Gallbladder removal and absorption
I recently had my gallbladder removed for suspicious polyps. Luckily these turned out to be non-malignant. Will I have a problem digesting and getting the benefits of Indole 3 Carbinol since I no longer have a gallbladder?
   A. Probably, but I can't say for sure without having seen actual studies with this nutrient in those who have had their gallbladder removed. It is not uncommon to have temporary digestive problems after cholecystectomy due to difficulty in handling fats and oils in the diet. Small meals eaten more frequently could be more tolerable rather than eating a large amount at one time.

Protate enlargement, BPH
I've been receiving many health letters and testimonials regarding Indole 3 Carbinol. They state this is the new remedy for BPH, claiming it actually shrinks the prostate. It recommends taking it with lycopene. What is your comments on this possible revelation?
   I have not seen any studies testing the relation of Indole 3 Carbinol and enlarged prostate. There are a number of herbs that have an influence on prostate tissue, and I prefer using a combination as opposed to one or two.

Q. I ordered at the site iherb com your Indole-3 Carbinol. I have just started using the capsules. Please tell me if you have effective materials against of psoriasis. My aunt asked me to make this request.
   A. I am not familiar with its use for psoriasis or other skin conditions.

Interactions with medications
Are there any contraindications for men taking I3C and Lipitor?
   A. I have not seen studies with this combination, so it is difficult to say. Lipitor, by itself, has side effects and it is not clear if an I3C supplement is added whether it would be helpful or harmful.

What is the difference between DIM and indole 3 carbonol? Also, is it safe to take either one while on birth control pills?
   We have not seen studies with the combination of DIM or indole 3 carbinol and birth control pills, so we can't comment on the safety or side effects with these combinations. Indole-3-carbinol is found in cabbage, cauliflower, and brussels sprouts. It is converted in the gut to diindolylmethane (DIM).

Can an individual take Indole 3 Carbinol I3C that has a suppressed immune system due to a liver transplant? This person is on Prograf and Coumadin.
   A. Not enough human research is available to know the answer to the question of its influence on the immune system after organ transplants.  There are too many variables at play, including the type of surgery and  immune suppressing drugs used.

We have a 1 yr old granddaughter who has been diagnosed with polyps on her vocal cords. Her doctor said he recommended Indole 3 Carbinol I3C because it has shown results that shrink the polyps. He asked if we could find a pediatric dosage. We looked it up to find that it would be 1/4th of a capsule that we would have to divide each day. What is your recommendation?
   I am not in a position to offer specific medical suggestions or dosages but I wish her well. If her doctor is recommending this nutrient, it is up to him or her to make the specific dosage recommendation.

I was wondering if you can take indole 3 carbinol while trying to conceive?
   We have not seen such studies in women who plan to be pregnant or are pregnant.

I want to take DIM because I have markers for increased risk for breast cancer but it gives me a migraine so my nurse practictioner suggested Indole-3-Carbinol (I3C) which I would take but I'm not sure if it is safe since i saw a few websites saying not to take it due to possible toxic effects? Could you let me know if Indole-3-Carbinol (I3C) is safe to take and is there a max dosage you would recommend? I am a healthy 45 yo otherwise and just want to take either that or DIM but the DIm, as I said gives me horrible headaches.
   I have not seen enough studies with this nutrient to know how safe it is for long term use or what the ideal dosage would be. Thus far I am not aware of any notable side effects mentioned in the medical literature.