Table of ContentsView AllTable of ContentsBenefitsSide EffectsDosage and Preparation
Table of ContentsView All
View All
Table of Contents
Benefits
Side Effects
Dosage and Preparation
I3C supplements are usually safe but can cause side effects like skin irritation, stomach issues, or tremors if taken in large doses. Some studies suggest it could even increase cancer risk, so it’s important to talk to a healthcare provider before using it.More research is needed to fully understand its effects.
In the United States, the Food and Drug Administration (FDA) does not regulate supplements like prescription drugs. This means some supplement products may not contain what the label says. Whenchoosing a supplement, look for independently tested products and consult a healthcare provider, registered dietitian nutritionist (RDN or RD), or pharmacist.
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Benefits of Indole-3-Carbinol
The primary claim about indole-3-carbinol is that if may help prevent certain types of cancer. It is also purported to help with systemic lupus erythematosus (SLE), viral infections, liver disease, and fibromyalgia. Here’s what the research says about the health benefits of I3C.
Cancer Prevention
The claimed benefits of I3C in cancer prevention include:
However, other studies contradict these claims including several studies that showed the opposite effect: I3C promoting tumor growth.
Systemic Lupus Erythematosus (SLE)
Systemic lupus erythematosus(SLE) is anautoimmune diseasein which the immune system mistakenly attacks healthy tissues throughout the body. About half of adults with SLE develop kidney disease.
I3C reduced kidney disease and prolonged life in animals, but a small study in females with SLE found 375 mg of I3C provided no symptom improvements after three months.The evidence concerning I3C for the treatment of systemic lupus erythematosus is limited.
Viral Infections
Some research suggests I3C may have antiviral effects.For example, I3C has been shown to prevent SARS-CoV-2 cells from multiplying.I3C has also been shown to stop the spread of coronavirus cells, which then inhibits viral production.
However, these results are based solely on lab research, so human studies are needed.
Liver Disease
Animal studies have demonstrated that I3C has preventive effects against alcohol-induced liver injury because of its antioxidant and anti-inflammatory properties, as well as slowing cell death. The researchers noted that I3C has a high potential for treating or preventing other types of liver injury associated with oxidative stress and inflammation.
However, this is in the early stages of research with human studies needed to determine if similar effects occur.
Possible Side Effects of Indole-3-Carbinol Supplements
Most people who take I3C tolerate it well. However, some studies have found I3C can cause symptoms, such as:
A couple of studies have shown that I3C may increase the risk of developing cancer or have toxic effects.However, these conclusions are not based on human findings.
Lab studies have shown that I3C may interact with certain drugs, such as Clozaril (clozapine) and Cymbalta (duloxetine).
Research says that high doses of I3C may not be more effective than smaller ones.It may be as beneficial to consume adequate amounts of cruciferous vegetables to get I3C.
Always talk to your healthcare provider before taking a supplement.
No specific safe dosage has been determined for humans. However, supplement companies suggest varying dosages between 200 to 800 mg per day. In human studies, doses were generally between 200 and 400 mg per day.
Summary
Although I3C is purported to help prevent cancer and several other conditions, conclusive human studies are needed to prove the supplement’s health benefits. Research is also needed to better understand any potential risks of supplementing with I3C.
17 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Memorial Sloan Kettering Cancer Center.Indole-3 Carbinol.Ashrafian L, Sukhikh G, Kiselev V, Paltsev M, Drukh V, Kuznetsov I, Muyzhnek E, Apolikhina I, Andrianova E.Double-blind randomized placebo-controlled multicenter clinical trial (phase IIa) on diindolylmethane’s efficacy and safety in the treatment of CIN: implications for cervical cancer prevention.EPMA J. 2015 Dec 21;6:25. doi:10.1186/s13167-015-0048-9Linus Pauling Institute.Indole-3-CarbinolBaez-Gonzalez AS, Carrazco-Carrillo JA, Figueroa-Gonzalez G, et al.Functional effect of indole-3 carbinol in the viability and invasive properties of cultured cancer cells. Biochem Biophys Rep. 2023 Jun 1;35:101492. doi: 10.1016/j.bbrep.2023.101492Suzui M, Inamine M, Kaneshiro T, et al.Indole-3-carbinol inhibits the growth of human colon carcinoma cells but enhances the tumor multiplicity and volume of azoxymethane-induced rat colon carcinogenesis.Int J Oncol. 2005;27(5):1391-1399.National Institute of Diabetes and Digestive and Kidney Diseases.Lupus & kidney disease (lupus nephritis).Centofanti F, Alonzi T, Latini A,et al.Indole-3-carbinol in vitro antiviral activity against SARS-Cov-2 virus and in vivo toxicity. Cell Death Discov. 2022 Dec 15;8(1):491. doi: 10.1038/s41420-022-01280-2Pennarossa G, Arcuri S, Pasquariello R, et al.Cruciferous vegetable-derived indole-3-carbinol prevents coronavirus cell egression mechanisms in tracheal and intestinal 3D in vitro models. Phytochemistry. 2023 Aug;212:113713. doi: 10.1016/j.phytochem.2023.113713Choi Y, Abdelmegeed MA, Song BJ.Preventive effects of indole-3-carbinol against alcohol-induced liver injury in mice via antioxidant, anti-inflammatory, and anti-apoptotic mechanisms: Role of gut-liver-adipose tissue axis. The Journal of Nutritional Biochemistry. 2018;55:12-25. doi: 10.1016/j.jnutbio.2017.11.011Rosen C A, et al.Preliminary results of the use of indole-3-carbinol for recurrent respiratory papillomatosis.Otolaryngol Head Neck Surg. 1998;118(6):810-815. doi: 10.1016/S0194-5998(98)70274-8Reed G A, Arneson D W, Putnam W C, et al.Single-dose and multiple-dose administration of indole-3-carbinol to women: pharmacokinetics based on 3,3'-diindolylmethane.Cancer Epidemiol Biomarkers Prev. 2006;15(12):2477-2481. doi:10.1158/1055-9965.EPI-06-0396Howard CG, Mullins JJ, Mitchell KD.Transient induction of ANG II-dependent malignant hypertension causes sustained elevation of blood pressure and augmentation of the pressor response to ANG II in CYP1A1-REN2 transgenic rats.Am J Med Sci. 2010 Jun;339(6):543-8. doi:10.1097/MAJ.0b013e3181d82a62Fletcher A, et al.Reversible toxic effects of the dietary supplement indole-3-carbinol in an immune compromised rodent model: Intestine as the main target.J Diet Suppl.2017;14(3):303-332. doi: 10.1080/19390211.2016.1215367Dashwood R H.Indole-3-carbinol: anticarcinogen or tumor promoter in brassica vegetables?.Chem Biol Interact. 1998;110(1-2):1-5. doi:10.1016/s0009-2797(97)00115-4Reed, G A, et al.A phase I study of indole-carbinol-3 in women: Tolerability and effects.Cancer Epidemiol Biomarkers Prev.2005;14(8);1953-1960. doi:10.1158/1055-9965.EPI-05-0121U. S. Department of Agriculture.Dietary Guidelines for Americans, 2020-2025.National Cancer Institute.Cruciferous vegetables and cancer prevention.
17 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Memorial Sloan Kettering Cancer Center.Indole-3 Carbinol.Ashrafian L, Sukhikh G, Kiselev V, Paltsev M, Drukh V, Kuznetsov I, Muyzhnek E, Apolikhina I, Andrianova E.Double-blind randomized placebo-controlled multicenter clinical trial (phase IIa) on diindolylmethane’s efficacy and safety in the treatment of CIN: implications for cervical cancer prevention.EPMA J. 2015 Dec 21;6:25. doi:10.1186/s13167-015-0048-9Linus Pauling Institute.Indole-3-CarbinolBaez-Gonzalez AS, Carrazco-Carrillo JA, Figueroa-Gonzalez G, et al.Functional effect of indole-3 carbinol in the viability and invasive properties of cultured cancer cells. Biochem Biophys Rep. 2023 Jun 1;35:101492. doi: 10.1016/j.bbrep.2023.101492Suzui M, Inamine M, Kaneshiro T, et al.Indole-3-carbinol inhibits the growth of human colon carcinoma cells but enhances the tumor multiplicity and volume of azoxymethane-induced rat colon carcinogenesis.Int J Oncol. 2005;27(5):1391-1399.National Institute of Diabetes and Digestive and Kidney Diseases.Lupus & kidney disease (lupus nephritis).Centofanti F, Alonzi T, Latini A,et al.Indole-3-carbinol in vitro antiviral activity against SARS-Cov-2 virus and in vivo toxicity. Cell Death Discov. 2022 Dec 15;8(1):491. doi: 10.1038/s41420-022-01280-2Pennarossa G, Arcuri S, Pasquariello R, et al.Cruciferous vegetable-derived indole-3-carbinol prevents coronavirus cell egression mechanisms in tracheal and intestinal 3D in vitro models. Phytochemistry. 2023 Aug;212:113713. doi: 10.1016/j.phytochem.2023.113713Choi Y, Abdelmegeed MA, Song BJ.Preventive effects of indole-3-carbinol against alcohol-induced liver injury in mice via antioxidant, anti-inflammatory, and anti-apoptotic mechanisms: Role of gut-liver-adipose tissue axis. The Journal of Nutritional Biochemistry. 2018;55:12-25. doi: 10.1016/j.jnutbio.2017.11.011Rosen C A, et al.Preliminary results of the use of indole-3-carbinol for recurrent respiratory papillomatosis.Otolaryngol Head Neck Surg. 1998;118(6):810-815. doi: 10.1016/S0194-5998(98)70274-8Reed G A, Arneson D W, Putnam W C, et al.Single-dose and multiple-dose administration of indole-3-carbinol to women: pharmacokinetics based on 3,3'-diindolylmethane.Cancer Epidemiol Biomarkers Prev. 2006;15(12):2477-2481. doi:10.1158/1055-9965.EPI-06-0396Howard CG, Mullins JJ, Mitchell KD.Transient induction of ANG II-dependent malignant hypertension causes sustained elevation of blood pressure and augmentation of the pressor response to ANG II in CYP1A1-REN2 transgenic rats.Am J Med Sci. 2010 Jun;339(6):543-8. doi:10.1097/MAJ.0b013e3181d82a62Fletcher A, et al.Reversible toxic effects of the dietary supplement indole-3-carbinol in an immune compromised rodent model: Intestine as the main target.J Diet Suppl.2017;14(3):303-332. doi: 10.1080/19390211.2016.1215367Dashwood R H.Indole-3-carbinol: anticarcinogen or tumor promoter in brassica vegetables?.Chem Biol Interact. 1998;110(1-2):1-5. doi:10.1016/s0009-2797(97)00115-4Reed, G A, et al.A phase I study of indole-carbinol-3 in women: Tolerability and effects.Cancer Epidemiol Biomarkers Prev.2005;14(8);1953-1960. doi:10.1158/1055-9965.EPI-05-0121U. S. Department of Agriculture.Dietary Guidelines for Americans, 2020-2025.National Cancer Institute.Cruciferous vegetables and cancer prevention.
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Memorial Sloan Kettering Cancer Center.Indole-3 Carbinol.Ashrafian L, Sukhikh G, Kiselev V, Paltsev M, Drukh V, Kuznetsov I, Muyzhnek E, Apolikhina I, Andrianova E.Double-blind randomized placebo-controlled multicenter clinical trial (phase IIa) on diindolylmethane’s efficacy and safety in the treatment of CIN: implications for cervical cancer prevention.EPMA J. 2015 Dec 21;6:25. doi:10.1186/s13167-015-0048-9Linus Pauling Institute.Indole-3-CarbinolBaez-Gonzalez AS, Carrazco-Carrillo JA, Figueroa-Gonzalez G, et al.Functional effect of indole-3 carbinol in the viability and invasive properties of cultured cancer cells. Biochem Biophys Rep. 2023 Jun 1;35:101492. doi: 10.1016/j.bbrep.2023.101492Suzui M, Inamine M, Kaneshiro T, et al.Indole-3-carbinol inhibits the growth of human colon carcinoma cells but enhances the tumor multiplicity and volume of azoxymethane-induced rat colon carcinogenesis.Int J Oncol. 2005;27(5):1391-1399.National Institute of Diabetes and Digestive and Kidney Diseases.Lupus & kidney disease (lupus nephritis).Centofanti F, Alonzi T, Latini A,et al.Indole-3-carbinol in vitro antiviral activity against SARS-Cov-2 virus and in vivo toxicity. Cell Death Discov. 2022 Dec 15;8(1):491. doi: 10.1038/s41420-022-01280-2Pennarossa G, Arcuri S, Pasquariello R, et al.Cruciferous vegetable-derived indole-3-carbinol prevents coronavirus cell egression mechanisms in tracheal and intestinal 3D in vitro models. Phytochemistry. 2023 Aug;212:113713. doi: 10.1016/j.phytochem.2023.113713Choi Y, Abdelmegeed MA, Song BJ.Preventive effects of indole-3-carbinol against alcohol-induced liver injury in mice via antioxidant, anti-inflammatory, and anti-apoptotic mechanisms: Role of gut-liver-adipose tissue axis. The Journal of Nutritional Biochemistry. 2018;55:12-25. doi: 10.1016/j.jnutbio.2017.11.011Rosen C A, et al.Preliminary results of the use of indole-3-carbinol for recurrent respiratory papillomatosis.Otolaryngol Head Neck Surg. 1998;118(6):810-815. doi: 10.1016/S0194-5998(98)70274-8Reed G A, Arneson D W, Putnam W C, et al.Single-dose and multiple-dose administration of indole-3-carbinol to women: pharmacokinetics based on 3,3'-diindolylmethane.Cancer Epidemiol Biomarkers Prev. 2006;15(12):2477-2481. doi:10.1158/1055-9965.EPI-06-0396Howard CG, Mullins JJ, Mitchell KD.Transient induction of ANG II-dependent malignant hypertension causes sustained elevation of blood pressure and augmentation of the pressor response to ANG II in CYP1A1-REN2 transgenic rats.Am J Med Sci. 2010 Jun;339(6):543-8. doi:10.1097/MAJ.0b013e3181d82a62Fletcher A, et al.Reversible toxic effects of the dietary supplement indole-3-carbinol in an immune compromised rodent model: Intestine as the main target.J Diet Suppl.2017;14(3):303-332. doi: 10.1080/19390211.2016.1215367Dashwood R H.Indole-3-carbinol: anticarcinogen or tumor promoter in brassica vegetables?.Chem Biol Interact. 1998;110(1-2):1-5. doi:10.1016/s0009-2797(97)00115-4Reed, G A, et al.A phase I study of indole-carbinol-3 in women: Tolerability and effects.Cancer Epidemiol Biomarkers Prev.2005;14(8);1953-1960. doi:10.1158/1055-9965.EPI-05-0121U. S. Department of Agriculture.Dietary Guidelines for Americans, 2020-2025.National Cancer Institute.Cruciferous vegetables and cancer prevention.
Memorial Sloan Kettering Cancer Center.Indole-3 Carbinol.
Ashrafian L, Sukhikh G, Kiselev V, Paltsev M, Drukh V, Kuznetsov I, Muyzhnek E, Apolikhina I, Andrianova E.Double-blind randomized placebo-controlled multicenter clinical trial (phase IIa) on diindolylmethane’s efficacy and safety in the treatment of CIN: implications for cervical cancer prevention.EPMA J. 2015 Dec 21;6:25. doi:10.1186/s13167-015-0048-9
Linus Pauling Institute.Indole-3-Carbinol
Baez-Gonzalez AS, Carrazco-Carrillo JA, Figueroa-Gonzalez G, et al.Functional effect of indole-3 carbinol in the viability and invasive properties of cultured cancer cells. Biochem Biophys Rep. 2023 Jun 1;35:101492. doi: 10.1016/j.bbrep.2023.101492
Suzui M, Inamine M, Kaneshiro T, et al.Indole-3-carbinol inhibits the growth of human colon carcinoma cells but enhances the tumor multiplicity and volume of azoxymethane-induced rat colon carcinogenesis.Int J Oncol. 2005;27(5):1391-1399.
National Institute of Diabetes and Digestive and Kidney Diseases.Lupus & kidney disease (lupus nephritis).
Centofanti F, Alonzi T, Latini A,et al.Indole-3-carbinol in vitro antiviral activity against SARS-Cov-2 virus and in vivo toxicity. Cell Death Discov. 2022 Dec 15;8(1):491. doi: 10.1038/s41420-022-01280-2
Pennarossa G, Arcuri S, Pasquariello R, et al.Cruciferous vegetable-derived indole-3-carbinol prevents coronavirus cell egression mechanisms in tracheal and intestinal 3D in vitro models. Phytochemistry. 2023 Aug;212:113713. doi: 10.1016/j.phytochem.2023.113713
Choi Y, Abdelmegeed MA, Song BJ.Preventive effects of indole-3-carbinol against alcohol-induced liver injury in mice via antioxidant, anti-inflammatory, and anti-apoptotic mechanisms: Role of gut-liver-adipose tissue axis. The Journal of Nutritional Biochemistry. 2018;55:12-25. doi: 10.1016/j.jnutbio.2017.11.011
Rosen C A, et al.Preliminary results of the use of indole-3-carbinol for recurrent respiratory papillomatosis.Otolaryngol Head Neck Surg. 1998;118(6):810-815. doi: 10.1016/S0194-5998(98)70274-8
Reed G A, Arneson D W, Putnam W C, et al.Single-dose and multiple-dose administration of indole-3-carbinol to women: pharmacokinetics based on 3,3'-diindolylmethane.Cancer Epidemiol Biomarkers Prev. 2006;15(12):2477-2481. doi:10.1158/1055-9965.EPI-06-0396
Howard CG, Mullins JJ, Mitchell KD.Transient induction of ANG II-dependent malignant hypertension causes sustained elevation of blood pressure and augmentation of the pressor response to ANG II in CYP1A1-REN2 transgenic rats.Am J Med Sci. 2010 Jun;339(6):543-8. doi:10.1097/MAJ.0b013e3181d82a62
Fletcher A, et al.Reversible toxic effects of the dietary supplement indole-3-carbinol in an immune compromised rodent model: Intestine as the main target.J Diet Suppl.2017;14(3):303-332. doi: 10.1080/19390211.2016.1215367
Dashwood R H.Indole-3-carbinol: anticarcinogen or tumor promoter in brassica vegetables?.Chem Biol Interact. 1998;110(1-2):1-5. doi:10.1016/s0009-2797(97)00115-4
Reed, G A, et al.A phase I study of indole-carbinol-3 in women: Tolerability and effects.Cancer Epidemiol Biomarkers Prev.2005;14(8);1953-1960. doi:10.1158/1055-9965.EPI-05-0121
U. S. Department of Agriculture.Dietary Guidelines for Americans, 2020-2025.
National Cancer Institute.Cruciferous vegetables and cancer prevention.
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