this was pretty much the subject line in one of our oncologists recent emails to me, and it’s a good question. Especially if you or someone you love has or is at higher risk for certain cancers, which is mostly everyone, but also if you just need another reason to eat your vegetables.
ok but first, what is DIM?
DIM, or diindolylmethane, is a breakdown product of the antioxidant indole-3-carbinol (I3C) found in cruciferous vegetables like broccoli, cauliflower, Brussels sprouts, kale and cabbage. DIM is a powerful anti-inflammatory, and because of this has been extensively studied in the scientific community for its possible protective properties against disease. More specifically, DIM may help block cancer-initiating events by increasing cellular detoxification and reducing inflammatory signaling. DIM also plays a role in estrogen metabolism. For those with or at risk for breast cancer, my area of specialty, DIM may be effective in modulating the initiation of cancer at all stages of breast tumor development. How cool is that?
spot the crucifers!
let’s talk research
as of this writing, much of the research on DIM has been done in cells or rodents, and though there have been some human observational studies published, finite recommendations can’t be made from the available date just yet. Even so, the studies have been very promising thus far. In breast cancer cell lines, the various actions of DIM has been shown to inhibit growth of human breast cancer cells in both estrogen-dependent and estrogen-independent cell lines. This is exciting because it may potentially expand therapeutic options for triple-negative breast cancer in the future. DIM has also been studied in combination with some chemotherapies, which is also promising but preliminary. I typically advise against taking any antioxidant supplements during chemotherapy treatment currently due to the possibility of affecting the treatment negatively (i.e., protecting cells we don’t want protected!), and research pointing to a possible synergistic relationship could be a game changer. But let’s be clear, MUCH more research needs to happen before recommendations and standards of practice are changed.
DIM-related recommendations I do make right now are more related to food choices. A recent meta-analysis of more than 18,000 individual cases suggested that overall high intake of cruciferous vegetables (> ¾ cup/day) was significantly associated with a 15% lower risk of breast cancer. In ladies with breast cancer, high cruciferous vegetable intake was associated with a 35% decrease in recurrence women taking Tamoxifen. So, it’s very rare that I meet with a patient without a mention of broccoli, cauliflower or Brussels sprouts. The fact that they are delicious and so versatile is an added bonus.
don’t forget that kale is a cruciferous veggie too!
so should I take a DIM supplement?
as of right now, I have to say no. Even though much of the research has been on very high concentrations of DIM, which is easier to obtain from a supplement, we need way more of it before recommending it be used. It’s also important to keep in mind that dietary supplements are not regulated by the FDA and finding a brand that has been reviewed by a third party for safety and ingredient content is key. Especially since DIM has limited bioavailability, so you really need a specialized formulation of DIM for any benefits.
ok, so what should I do?
eat more vegetables! Often when I suggest adding more cruciferous veggies to their diets, people cringe a bit. This could be because they commonly cause gas or they associate them with a sub-par taste thanks to a boring cooking method or no seasoning. Both concerns can be remedied! When cruciferous veggies are consumed on a regular basis, our intestinal microflora can adapt and produce less gas (this also goes for beans!). And, cooking methods are everything when it comes to cruciferous vegetables. Roasting brings out delicious flavor by caramelizing them, and using various herbs and spices can up the flavor game even more. Here are two of my favorite, simple recipes that are always crowd pleasers.
roasted curried cauliflower (serves 4-5)
- 1 head cauliflower
- 1-2 tbsp. extra virgin olive oil
- 2 tsp curry powder
- 2 tsp turmeric
- ½ tsp black pepper (this enhances absorption of curcumin, the powerful antioxidant found in turmeric)
- Pinch sea salt
preheat oven to 425° F. Chop cauliflower into bite size pieces and spread evenly on large parchment or tinfoil-lined baking sheet. Drizzle olive oil over pieces and sprinkle curry powder, turmeric, black pepper evenly, season with pinch of sea salt. Place baking sheet into the oven and roast for 20-25 minutes, until cauliflower is tender and browned. Enjoy warm and store leftovers in a sealed container for up 3-4 days.
crispy roasted brussels sprouts (serves 4-5)
- 1 pound Brussels sprouts, halved
- 1-2 tbsp. extra virgin olive oil
- Sea salt and pepper to taste
preheat oven to 425° F. Place Brussels sprouts on a parchment or tinfoil-lined baking sheet. Drizzle with olive oil and sprinkle sea salt and pepper. Roast for about 15 minutes, and then toss the Brussels sprouts with a spatula. Roast for an additional 5 minutes, then turn oven off and let Brussels sit in the oven for 10-15 minutes, until tender and caramelized. Enjoy warm and store leftovers in a sealed container for up 3-4 days.
*disclaimer – this post is for informational purposes only and not meant to serve as individual medical advice or medical nutrition therapy.