Indole-3-Carbinol

Indole-3-Carbinol (I3C)

• What Is It?

  • Indole-3-carbinol (I3C) is formed from the breakdown of a substance called glucosinolate glucobrassicin. Glucobrassicin is found in vegetables such as broccoli, brussels sprouts, cabbage, collards, cauliflower, kale, mustard greens, turnips, and rutabagas.  

    
    

• How Does It Work in the Body?

  • I3C is known to stimulate detoxifying enzymes in the gut and liver. Diets high in these vegetables slow cancer growth in animals, believing I3C to be a good candidate for cancer prevention.

• What Is It Used for?

  • Cancer Prevention

    • Studies indicate that I3C may have protective qualities against various cancers; however, some animal studies suggest that I3C supplementation might have tumor-promoting effects. Further research is required.

  • Treatment of Viral Infections

    • Lab studies suggest immune function and antiviral effects, but no studies have been conducted in humans.

• Precautions/Side Effects:

  • Mild adverse events have been reported dependent on dosage and use: abdominal discomfort, bloating, nausea, vomiting, asthma, breast tenderness, chest pain, constipation, diarrhea/loose stools, dizziness, headache, musculoskeletal complaints, rash, sciatic nerve pain, and upper respiratory symptoms.

• Evidence for and Against:

  • New anticancer agents with overlapping underlying mechanisms have emerged via structural optimization of I3C and its metabolite 3,3'-diindolylmethane (DIM), which may provide therapeutic advantages with respect to chemical stability and anti-tumor potency.

  • Numerous in situ studies have implicated indole-3-carbinol as one of the phytochemicals with anticancer properties. Recent studies on the role of I3C in Arabidopsis (rockcress) opens the door for cross-kingdom comparisons that can help in understanding the role of this chemical in both plant biology and combatting cancer.

• Dosage:

  • There is not enough scientific information to determine an appropriate range of doses for I3C.

• Interactions:

  • Laboratory studies suggest I3C induces CYP 1A2; however, the clinical relevance is unproven.