IndoleMAX™ Indole-3-Carbinol (I3C)
IndoleMAX™ Indole-3-Carbinol (I3C)
VitaMonk Indole i3c
IndoleMAX™ Indole-3-Carbinol (I3C)
IndoleMAX™ Indole-3-Carbinol (I3C)
VitaMonk Indole i3c

IndoleMAX™ Indole-3-Carbinol (I3C)


IndoleMAX™ is a high quality I3C (or indole-3-carbinol) supplement. I3C is a natural precursor to DIM (or diindolylmethane). This powerful substance is found in healthy superfoods like broccoli, brussels sprouts and kale. 

Indole-3-carbinol is a naturally occurring estrogen blocker.

Supplementing it regularly can help you support:

  • Healthy estrogen levels in men and women
  • Blocking estrogen for bodybuilders - increasing the hormonal ratio of testosterone to estrogen in your blood
  • Boosted sex drive and energy
  • Menopause and estrogen dominance in women
  • Management of noncystic hormonal acne, hair loss and even weight loss
  • Overall healthy estrogen metabolism 

Do you need to minimize the estrogen flowing through your veins (and get the health benefits associated with it)? Then I3C is an essential supplement to take to reach your health goals.

Healthy Hormone Levels & Normal Estrogen Metabolism

The anti estrogen effect of I3C makes it an effective way to balance estrogen in your body. You can use it to support either drastic decreases or increases of this hormone.

I3C is an all-natural substance, which is abundant in healthy vegetables like kale and broccoli.

I3C works by inhibiting an enzyme which converts testosterone to estrogen. Another effect it has is to convert stronger forms of estrogen into weaker forms. And if you take very large doses, it can reverse the process - increasing the creation of estrogen. 

In other words - I3C is a very powerful tool you can use to keep your estrogen levels in a healthy range.

IndoleMAX™ Indole-3-Carbinol (I3C)

The Support You Need During Menopause

I3C is a vital supplement in helping women maintain balanced estrogen levels as well as bodybuilders and athletes trying to gain that edge.

Use it to promote healthy estrogen levels and support:

  • Healthy menopause
  • Clear skin and strong hair
  • Increased weight loss, energy and sex drive
  • Management of noncystic hormonal acne.
  • Optimal muscle gains for bodybuilders and athletes

Use IndoleMAX™ to support healthy estrogen metabolism, and promote balanced estrogen levels.

IndoleMAX™ Indole-3-Carbinol (I3C)

Safe, and Effective

VitaMonk's products are formulated by licensed doctors and manufactured in state-of-the-art facilities following strict GMP compliance standards.

We go to great lengths to make sure our supplements meet the highest safety standards. When you use our supplements, you KNOW that you’ll only get the highest quality ingredients that have the most scientific backing to help you get results.

IndoleMAX™ Indole-3-Carbinol (I3C)
Get IndoleMAX™ Indole-3-Carbinol (I3C)

We are so confident that you'll love this product that it comes with a 100% money back guarantee. If for any reason you’re not completely satisfied with this supplement after using it, just let us know.

An Overview of Indole 3 Carbinol

Indole 3 carbinol (I3C) is derived from the breakdown of glucobrassicins; these compounds are naturally found in cruciferous vegetables such as broccoli, cabbage, and sprouts. 

Once inside the stomach I3C can be converted into the biologically active product 3,3'-diindolylmethane (DIM). This plays a role in estrogen homeostasis. Where it helps to balance healthy levels of estrogens and to maintain a beneficial ratio of low to high estrogenic metabolites.

As it is thought that Indole-3-carbinol may have a beneficial role in supporting the body it has been the focus of much research [1–4]. 

One of the main reasons that people may be interested in I3C is for its role in the blocking estrogen.

I3C Metabolism and Availability

As mentioned above, I3C is a common component of members of the Brassica plant family. These plants are rich in glucosinolates such as glucobrassicin. Upon breakdown of a plant’s cell wall glucobrassicin is hydrolyzed into Indole 3 carbinol by the enzyme myrosinase. In the stomach (an acidic environment), IC3 is then able to form complexes with other bioactive products, these include DIM and cyclic trimer (CT). It is these products that act as biologically active agents, as opposed to IC3 itself [5].

Unfortunately, when vegetables are boiled plant myrosinase becomes inactivated. This greatly diminishes catalyzes of glucobrassicin into I3C by myrosinase. Fortunately, some conversion into I3C can still occur in the body due to the presences of intestinal bacteria. 

Biotransformation and DNA Binding

DIM and indole[3,2-b]carbazole (ICZ) are produced when I3C is broken down in the body. [6] These acidic products have been linked with the support of steroid hormone metabolism and removal from the body of toxins and other undesirable bioactive compounds.

DIM and ICZ are able to bind to the cytoplasmic protein AhR (aryl hydrocarbon receptor). This allows the complex to move into the nucleus. It is then able to bind to the Ahr nuclear translocator (Arnt) protein and specifically bind gene DNA sequences. This leads to an increase in the transcription of phase I (e.g., cytochrome P450; CYP)) and II biotransformation enzymes. These enzymes have major roles in the support of metabolism and the clearing away of unwanted metabolites in healthy individuals.

Estrogen Metabolism and Receptor Activity

Estrogens are a group of sex hormones known to support sexual and reproductive development. A woman naturally produces estrogen in her ovaries, and this hormone class is also produced at lower levels in the adrenal glands and by fat cells.

In the body, estrogens bind to receptors to form complexes that deploy regulatory effects on musculoskeletal and cardiovascular systems, menstruation, urinary and reproductive tracts, bones, skin, hair, pelvic muscles, breasts, and the heart and brain. Estrogen is also responsible for secondary sexual characteristics such as the development of hair during puberty.

Indole 3 carbinol has been reported to block the transcription of genes transcripted by 17β-estradiol in vitro. This role as an estrogen blocker may act through the support of degradation of estrogen receptors or through competition with coactivators [7]. 

I3C may help to support healthier levels of lower estrogenic metabolites such as 2-hydroxyestrone. One of the roles of 17β-estradiol (see above) is to act as a substrate in the creation of 16α-hydroxyestrone (this reaction is not reversible). This is a highly estrogenic metabolite and is thus likely to have negative impacts on human health [8]. IC3 may help to support healthier ratios of 2-hydroxyestrone to 16α-hydroxyestrone in healthy women [9].

Cell Cycle Arrest and Apoptosis

The I3C derivative DIM is able to support healthy apoptosis in dysfunctional cells that do not respond to normal death signals, and both IC3 and DIM may also be involved in the blocking of unhealthy blood vessel development [10]. IC3 has also been reported to activate cell cycle arrest in vitro.

    Citations, Reviews, Abstract, and References

    [1] Sarkar et al. Cellular signaling perturbation by natural products. Cell Signal. 2009 Nov;21(11):1541-7. doi: 10.1016/j.cellsig.2009.03.009. Epub 2009 Mar 16.

    [2] Minich and Bland. A review of the clinical efficacy and safety of cruciferous vegetable phytochemicals. Nutr Rev. 2007 Jun;65(6 Pt 1):259-67.

    [3] Broadbent and Broadbent. 1. The chemistry and pharmacology of indole-3-carbinol (indole-3-methanol) and 3-(methoxymethyl)indole. [Part II]. Curr Med Chem. 1998 Dec;5(6):469-91.

    [4] Vahid et al. The role dietary of bioactive compounds on the regulation of histone acetylases and deacetylases: a review.

    [5] Bjeldanes 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. Proc Natl Acad Sci U S A. 1991;88(21):9543-9547.

    [6] Anderton et al. Liquid chromatographic assay for the simultaneous determination of indole-3-carbinol and its acid condensation products in plasma. J Chromatogr B Analyt Technol Biomed Life Sci. 2003 Apr 25;787(2):281-91. 

    [7] Enríquez et al. The anti-estrogenic activity of indole-3-carbinol in neonatal rat osteoblasts is associated with the estrogen receptor antagonist 2-hydroxyestradiol. J Endocrinol Invest. 2016 Oct;39(10):1149-58. doi: 10.1007/s40618-016-0494-9.

    [8] Bradlow et al. 2-Hydroxyestrone: the 'good' estrogen. J Endocrinol. 1996;150 Suppl:S259-265. 

    [9] Kasim-Karakas et al. Effects of prune consumption on the ratio of 2-hydroxyestrone to 16 alpha-hydroxyestrone. Am J Clin Nutr. 2002 Dec;76(6):1422-7. 

    [10] Wu, Lin, and Chen. Inhibition of cell proliferation and in vitro markers of angiogenesis by indole-3-carbinol, a major indole metabolite present in cruciferous vegetables. J Agric Food Chem. 2005;53(13):5164-5169. 

    [11] McNaughton and Marks. Development of a food composition database for the estimation of dietary intakes of glucosinolates, the biologically active constituents of cruciferous vegetables. Br J Nutr. 2003;90(3):687-697.

    Further Reading

    • WebMD: Vitamins and Supplement Guide: I3C uses, side effects, and dosing. - {} 
    • What are Estrogens? - {}
    • University of Rochester Medical Center: Estrogen's Effects on the Female Body - {}
    • Reddit: Effect on libido - {} 
    • Bodybuilding Forums: How much I3C should I be taking? - {}

    Which Foods are rich in Indole 3 carbinol?

    Cruciferous vegetables contain the most amounts of I3C. Good natural sources to include in your diet include garden cress (3.9 mg/g); Brussels sprouts (2.4 mg/g); Horseradish (1.6 mg/g); Kale (1.0 mg/g); Cabbage (0.6 to 0.8 mg/g, depending on variety); Kohlrabi (0.5 mg/g); and Cauliflower (0.4 mg/g) [11].

    Please note that these concentrations are for raw vegetables. The cooking of vegetables will have a massive negative effect on the bioavailability of I3C and its conversion into its derivative products known to have bioactive roles, such as DIM. 

    I3C vs DIM?

    DIM is a natural product produced from the breakdown of I3C in the stomach.

    What is the role of indole 3 carbinol for bodybuilding?

    This phytochemical may help to support a healthier hormonal balance in both men and women. It may help to block estrogen receptors and thus help support in lowering the levels of highly estrogenic metabolites.

    What does indole 3 carbinol smell like?

    The smell and taste is not the most pleasant.

    What is indole 3 carbinol good for?

    It helps to support the balance of estrogen levels.

    When to take indole-3-carbinol?

    Many people take it before a meal to help mask its taste. 

    Who should take indole 3 carbinol?

    People wishing to balance their hormone levels, such as women undergoing the menopause. 

    Where are estrogens synthesized and what is their role?

    These are naturally produced by the ovaries, placenta, and adrenal cortex in the cortex. In addition to being created in the adrenal gland, men can also synthesize it in the testes in small amounts. They are mainly involved in controlling female sexual development and function.

    What are the main types of endogenous estrogen?

    Estradiol, estriol, and estrone. 

    Where does indole 3 carbinol come from?

    It is a derivative of glucobrassicin, which is a glucosinolate found in green leafy veg.

    How much indole 3 carbinol do you suggest per day?

    Most of the research work performed uses I3C at dosage of 200 to 400 mg. So one VitaMonk IndoleMax tablet per day should be adequate for most people’s needs. 

    What is the makeup of VitaMonk IndoleMAX™ capsules?

    Each capsule contains 250 mg of Indole 3 carbinol. Other ingredients include vegetable cellulose, white rice flour, and magnesium stearate. This makes our product suitable for vegetarians. They are also gluten free. 

    Does it have any verified interactions with drugs and medications?

    Yes. It is known to have moderate interactions with medications that can get changed by the liver. 

    I3C may speed up the rate that these medications are broken down by the liver and thus may reduce their effectiveness. Some examples (amongst many) of a drug that may be altered by the liver include clozapine, propranolol, and zileuton. If you are taken any form of medication it is recommended that you consult with your doctor / general practitioner for advice before undergoing any form of supplemental regime. 

    Where to find indole 3 carbinol?

    You can buy it right here or purchase it from our Amazon store. Rest assured that you can expect only the highest quality products from VitaMonk. We now offer free shipping for those making purchases on the web of $35 and over.