Indole-3-Carbinol (I3C) 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 normal 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 with the highest level of Flax Lignans available, which are also beneficial in supporting healthy normal hormone balance.*
I3C Fact Sheet
Neil E. Levin, CCN, DANLA
Indole-3-Carbinol (I3C), product #3056, presented unique challenges before it could come to market. A sulfurous phytonutrient compound found in cruciferous vegetables such as broccoli and cabbage, I3C is very difficult to stabilize in order to maintain potency and an adequate shelf life. It took months of lab work and stability testing to match the best dose of I3C with a synergistic base that did not harm its stability, and it had to be in a glass bottle with a strong freshness packet.
These strong quality control concerns are a measure of how seriously the folks at Now Foods try to follow Good Manufacturing Practices to have a reasonable assurance that what is on the label is also in the product when you use it. It also raises some questions about other brands when their product shows up in plastic bottles or with volatile ingredients in their base:
Did they really do their homework in the lab?
Do they even use a lab?
Does their formula hold up to give you the full label dose many months after it’s made?
Would they delay introduction of an important new product for months just to make sure of the stability and potency, to assure that their customers will get an effective product that’s honestly labeled?
What are the benefits to taking I3C?
I3C helps to regulate cell growth rates, and helps to change a strong and inflammatory form of estrogen (estradiol) into a safer, less aggressive form (estrone). In technical terms, I3C influences our bodies to favor the 2-hydroxylation metabolic pathway to increase the ratio of 2-hydroxysterone to 16a-hydroxyestrone. It may also be able to influence estradiol activity in neighboring cells to also be less aggressive at triggering cell growth. The regulation of estrogen-related cell growth is considered a factor into whether one is more prone to develop certain cancers, so dietary nutrients that normalize cell growth are considered protective. Cells need to be able to repair and grow at normal rates. Uncontrolled growth can be very dangerous. I3C helps trigger cell death in abnormal cells so they won’t become a bigger problem over time.
Other studies indicate that I3C has the same protective effects for testosterone and other androgenic hormones as for estrogens. This means that it’s protective for both men and women.
I3C is also an antioxidant that protects cells from harmful bacteria that can make cells behave erratically or become harmful to the body. It may also protect cells against the effects of dioxin and other estrogenic compounds found in pesticides, plastics and other chemical sources. In some studies it has even been protective against known carcinogens, protecting both prostate and breast tissues. I3C has also shown that it may protect DNA from chemical damage.
While I strongly recommend eating foods that are rich in phytonutrients such as I3C, it may be useful to have an active, stabilized form available as a supplement. Now’s formula also uses LinumLife concentrated flax lignans, a powerful form of phytoestrogens that are useful for both men and women. The lignans in LinumLife are about 10x more concentrated than in flaxseeds and about 30x more concentrated than in flax oil. Lignans are converted to very weak estrogens in the body, providing a better hormone balance for both sexes. This action affects not only obvious hormonal issues and cell growth, but also the healthy function of prostate and breast cells, skin and bone health and prevention of hair loss. Lignans also may help to regulate blood sugar and cholesterol.
I3C vs. DIM: One conversion fraction of I3C is 3,3'-diindolylmethane (DIM). DIM is often used as a substitute for I3C because of the difficulty in stabilizing I3C, though the other metabolite compounds in I3C are also considered beneficial and synergistic. NOW has worked out a solution to this problem, allowing the use of the full, stabilized I3C complex.
CAUTIONS: People should avoid flaxseed and supplements made with LinumLife if they have a known allergy to flaxseed, flaxseed oil or any member of the Linaceae or Linum plant families.
I3C is absorbed and metabolized by reacting with stomach acid. Those with low stomach acid or who are taking antacids may not absorb this formula well. There are ways that nutritional experts use to improve stomach acid production for those who need it, and a hydrochloric acid supplement may help for some people. Low stomach acid may interfere with absorption of many nutrients and remove an important immune barrier (stomach acid).
Pregnant and lactating women and people using prescription drugs should consult their physician before taking any dietary supplement, including those made with LinumLife and I3C.
DOSE: A mild preventive dose is one per day. A full dose is 2 per day, preferably in divided doses.
COMPLEMENTARY PRODUCTS: Soy products that are rich in isoflavones, which are phytoestrogens. Fermented and non-genetically engineered soy products are preferred. Flaxseeds and flax oil. Fish and fish oil. Fresh vegetables, especially cabbage, broccoli, garlic, onions, etc.
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Chen D, Carter TH, Auborn KJ. Apoptosis in cervical cancer cells: implications for adjunct anti-estrogen therapy for cervical cancer. Anticancer Res. 2004 Sep-Oct;24(5A):2649-56. PMID: 15517869