DIM/IC3 Supplementation Blocks Estrogen, Dihydrotestosterone & mTOR


What is DIM / IC3?

Remember when your mother used to always tell you to eat your vegetables, especially those dark leafy greens? Turns out that the broccoli your mother kept hounding you about had more nutrients inside of it than she realized.

Dark leafy greens and cruciferous vegetables contain a compound called indole-3-carbinol (IC3). Within IC3 is another compound called DIM (3,3′-diindolylmethane). While it’s more common to see DIM supplements, DIM is a byproduct of IC3 and therefore we will discuss them together.

What are the Benefits of DIM / IC3?

Before we discuss the benefits of DIM / IC3 as they relate to testosterone, let’s take a look at other things that DIM / IC3 may have a positive influence on.

May Protect Against Cancer

A study published in Integrative Cancer Therapies determined that if the average individual living in the United State would simply add more cruciferous vegetables (e.g., broccoli, spinach, kale) into their diet, the rate of cancer would drop by 20%.

Since IC3 and DIM are by-products of cruciferous vegetables, scientists determined that IC3 and DIM supplements may be an effective way to prevent certain types of cancer. (1)

Prevents Estrogen Dominance

Estrogen dominance is a condition that is far more common in the modern day than it was 50 years ago.

Why? The global diet is more focused on testosterone lowering foods while putting more estrogenic compounds in to the environment. From pesticides that spike estrogen levels to plastics in our homes, we’re surrounded by estrogen boosting things.

DIM and IC3 supplementation may be a powerful way to prevent estrogen dominance. For women, this means a drastic reduction in breast cancer risk and for men, it means avoiding the side effects of estrogen dominance such as man-boobs, mood swings, and low libido. (2)

Does DIM / IC3 Block Estrogen and Increase Testosterone?

Does DIM Block Estrogen?Supports Estrogen Metabolism

As I mentioned above, DIM and IC3 help to encourage estrogen metabolism. As a result, both men and women can avoid the side effects of estrogen dominance.

However, just because DIM may block estrogen from reaching elevated levels does not automatically mean that testosterone levels will increase. You have to remember that your body is constantly striving for homeostasis.

When you supplement with steroids, for example, your testosterone increases and your body naturally increases estrogen as well to balance things out. Your estrogen isn’t increasing; therefore, the body has no reason to increase testosterone.

No Study Confirms Testosterone Boosting

Continuing with the point above, DIM and IC3 aren’t bad for your testosterone levels but there are no credible human-based scientific studies available that demonstrate these nutrients as being direct testosterone boosters.

One study suggests that DIM may lower DHT (dihydrotestosterone) levels but does not increase testosterone by default. (3)

DIM / IC3: The Bottom Line

It’s important to avoid allowing estrogen to become dominant in the body for both men and women. DIM and IC3 may be a useful and natural way to keep estrogen in its place; however, to say that the two are effective testosterone boosters is a bit misleading.

You can use DIM or IC3 as a part of a testosterone boosting program but on their own, they will not boost your testosterone levels. One thing to take note of is that you should not be taking DIM in place of a diet rich in cruciferous vegetables. There is no pill that will substitute your required 7 to 10 servings of fruits and vegetables each day.

Additional Editor’s Notes

iTestosterone Founder Robert ClarkI agree with David’s information in the above article. I do want to mention a few of my personal thoughts on DIM too, however, as in my research I have found some pretty big potential issues with 3,3′-diindolylmethane supplementation.

Like David, I am big on getting your IC3 and DIM from cruciferous vegetables where you are ingesting it, in its natural state.

One of the easiest ways to increase your daily cruciferous vegetable intake is by making a daily smoothie or taking a maca supplement!

Maca root is actually a cruciferous vegetable and is one of the highest natural sources of DIM available.

However, I am going to discuss some reasons below why I feel supplementing with diindolylmethane in particular, may actually be a negative, rather than a positive.

DIM Blocks DHT

DIM Blocks DHTAs David mentioned above in his article, diindolylmethane (DIM) can block dihydrotestosterone (DHT).

DHT tends to get a bad wrap because it’s been associated with hair loss. However, the science doesn’t actually point to this.

While DHT does likely play a role in hair loss, there is a whole host of factors which go into it and exactly what role DHT plays is not clear.

With that said, it does not appear that DHT in and of itself causes hair loss. In fact, more modern research says that elevated estrogen levels in men causing a hormone imbalance may be the biggest culprit behind hair loss. (4)

But DIM may block both estrogen and DHT so shouldn’t that be a good thing? At first glance you would think so but once again, the actual science says something else.

For one thing DHT itself is a powerful estrogen blocker. (5)

So if you are blocking DHT you are blocking one of the most important tools your body has to block estrogen, which may completely cancel out any estrogen blocking benefit you get from DIM.

Second of all, DIM has been shown again and again to inhibit angiogenesis. (6, 7, 8)

This means it prevents the formation of new blood vessels which is critical to follicle (hair) growth.

There has also been some bad publicity about DHT and prostate issues but once again, the real science behind prostate problems says something completely different than the stories the media and big pharma has been feeding us.

You can read more about all of this in my article on DHT.

Lastly, it’s worth mentioning that dihydrotestosterone is much more anabolic than testosterone. So if you want to increase your muscle size and strength, you don’t want to inhibit your DHT!

DIM Blocks mTOR

One of the worst aspects of high quantities of DIM coming from direct supplementation is that in blocks mTOR which is otherwise known as mammalian target of rapamycin and FK506-binding protein 12-rapamycin-associated protein 1 (FRAP1). (9)

Just keeping it simple here, mTOR is absolutely critical to growth hormone or (IGF-1) and building muscle mass. (10)

DIM May Cause Testicular Degeneration

DIM Causes Testicular DegenerationIn rats, DIM has been shown to lead to histological degeneration of testicular tissues.

Testicular degeneration with DIM supplementation has not been tested for on humans and likely never well, since nobody wants to volunteer up a testicle.

I also want to point out that how a nutrient will react in the human body, often times is different than the reaction a rat gets. In human males, this may not have any negative impact on the testicles what-so-ever.

Still, in my opinion, this is a big cause for concern and obviously something you don’t want to happen to you and I wouldn’t be doing my due diligence if I didn’t bring the study to your attention, so you may make a fully informed choice. (11)

My Conclusion

There are a lot of incredibly positive benefits to IC3 and DIM such as lowering inflammation and preventing cancer.

However, when you take these compounds out of foods and concentrate them into high dose supplement form, there are negative factors associated with them that just doesn’t make it worth the risk.

When you consume IC3 and DIM in the form of cruciferous vegetables (broccoli, cabbage, kale, maca root, etc.) you get the benefit of it but do not have these same risk factors because the amount of food you would have to eat to equal the same amount of diindolylmethane in supplement form, is for all practical purposes impossible.

Check out my article on the Best Testosterone Boosters that really work!


  1. Keck AS, Finley JW. Cruciferous vegetables: cancer protective mechanisms of glucosinolate hydrolysis products and selenium. Integr Cancer Ther. 2004 Mar;3(1):5-12. – Link
  2. Rajoria S, Suriano R, Parmar PS, et al. 3,3′-Diindolylmethane Modulates Estrogen Metabolism in Patients with Thyroid Proliferative Disease: A Pilot Study. Thyroid. 2011;21(3):299-304. doi:10.1089/thy.2010.0245. – Link
  3. Le HT, Schaldach CM, Firestone GL, Bjeldanes LF. Plant-derived 3,3′-Diindolylmethane is a strong androgen antagonist in human prostate cancer cells. J Biol Chem. 2003 Jun 6;278(23):21136-45. Epub 2003 Mar 27. – Link
  4. Men: Stop Thinking Your Hair Loss Is Due To High Testosterone. Perfect Hair Health – Link
  5. Antiestrogenic action of dihydrotestosterone in mouse breast. Competition with estradiol for binding to the estrogen receptor. Casey RW, Wilson JD. – Link
  6. 3,3′-Diindolylmethane inhibits angiogenesis and the growth of transplantable human breast carcinoma in athymic mice. Xiaofei Chang, Janet C. Tou, Chibo Hong, Hyeon-A. Kim, Jacques E. Riby, Gary L. Firestone, Leonard F. Bjeldanes – Link
  7. Inhibition of Angiogenesis and Invasion by 3,3′-Diindolylmethane Is Mediated by the Nuclear Factor–κB Downstream Target Genes MMP-9 and uPA that Regulated Bioavailability of Vascular Endothelial Growth Factor in Prostate Cancer. Dejuan Kong, Yiwei Li, Zhiwei Wang, Sanjeev Banerjee and Fazlul H. Sarkar- Link
  8. Mammalian Target of Rapamycin Repression by 3,3′-Diindolylmethane Inhibits Invasion and Angiogenesis in Platelet-Derived Growth Factor-D–Overexpressing PC3 Cells. Dejuan Kong, Sanjeev Banerjee, Wei Huang, Yiwei Li, Zhiwei Wang, Hyeong-Reh Choi Kim and Fazlul H. Sarkar – Link
  9. Inhibition of PI3K/Akt/mTOR Signaling by Natural Products. Shile Huang – Link
  10. Anabolic and catabolic pathways regulating skeletal muscle mass. John J. McCarthy and Karyn A. Esser – Link
  11. 3,3 diindolylmethane leads to apoptosis, decreases sperm quality, affects blood estradiol 17 β and testosterone, oestrogen (α and β) and androgen receptor levels in the reproductive system in male rats. Aksu EH, Akman O, Ömür AD, Karakuş E, Can I, Kandemir FM, Dorman E, Uçar Ö. – Link