There’s so much nutritional goodness in cruciferous vegetables. You’re aware that cruciferous vegetables are healthy, but there’s more to them than meets the eye. Beyond macronutrients, vitamins, and minerals, cruciferous vegetables, or crucifers, contain compounds that give these nutritious vegetables their health-promoting properties. Cruciferous vegetables are a vegetable group that includes:
- Bok Choy
- Broccoli
- Brussels Sprouts
- Cabbage
- Chinese Cabbage (Napa)
- Kale (Curly or Lacinato)
- Collard Greens (English)
- Kohlrabi
- Turnips
- Broccolini
- Watercress
- Mustard greens
- Kale
- Cauliflower
- Radishes
- Arugula
It’s clear that these vegetables are a nutrient-dense choice for your diet cruciferous vegetables are also known for increasing the number of indoles in your diet. The two of importance are indole-3-carbinol (I3C) and the more active form called 3,3′-diindolylmethane (DIM).
What are indoles? In chemical terms, they’re a class of aromatic heterocyclic organic compounds with a five-membered ring containing two nitrogen atoms. Don’t worry! That’s not something you need to remember.
Indoles are naturally present in plants as they help the plant survive in harsh environments and act as pollinator attractors. Some indoles function as insecticides while others reduce pathogens that may harm the plant.
Cruciferous vegetables contain compounds called glucosinolates, a type of sulfur compound. When you chew and digest cruciferous vegetables, you break down glucosinolates in these foods into indoles. For humans, indoles appear to have health benefits and you get those benefits when you eat cruciferous vegetables. Let’s look at some of the health benefits indoles in cruciferous vegetables offer.
Reduced Inflammation
Studies show that I3C may reduce inflammation by blocking the activity of signaling molecules that boost the body’s inflammatory response. That’s important since inflammation plays a key role in many chronic diseases including cardiovascular disease, type 2 diabetes, infections, and autoimmune diseases. It’s better to calm inflammation with foods than medications.
Non-steroidal anti-inflammatory medications (NSAID), like Advil, carry an increased risk of bleeding from the digestive tract and cause a rise in blood pressure, so foods, like cruciferous vegetables, may provide a natural way to subdue the body’s inflammatory response.
Potential Anti-Cancer Benefits
Scientists have looked at indole-3-carbinol for its role in protecting against certain types of cancer. The mechanism behind this effect is that I3C blocks the production of carcinogenic nitrosamines, which are known to cause stomach cancer. Nitrosamines can bind with DNA and cause mutations that could lead to cancer.
You’re exposed to low levels of nitrosamines through the water you drink, dairy products, and processed meat. Recently, the Food and Drug Administration recalled some medications because they contained nitrosamine contamination.
Research shows indole-3-carbinol may also block the growth of cancers of the colon, lung, and liver. Some studies show DIM may help fight estrogen-dependent cancers, such as breast cancer. DIM helps break down estrogen to a form that’s less carcinogenic and easier to excrete from the body.
One study found that women who ate more than three servings of cruciferous vegetables per week had a lower risk of developing breast cancer than those who ate fewer than one serving per week. Despite these benefits and the availability of indole-3 carbinol and DIM supplements, it’s best to get indoles from food sources.
Some research finds that, under certain conditions and at certain concentrations, indoles could stimulate cancer growth. It appears that consuming concentrated amounts of indoles, as by taking a supplement, could have the opposite effect.
Indoles May Help Protect Your Intestinal Lining
The lining of your intestinal tract consists of a single layer of cells. This thin lining is fragile and prone to damage. When the cells that line the intestinal tract become damaged, it can lead to inflammation. Studies in mice show that indoles in cruciferous vegetables may protect against damage that contributes to health issues like inflammatory bowel disease. Indole-3-carbinol reduces inflammatory chemicals that damage the gut.
Conclusion
Cruciferous vegetables are one of the best sources of indoles. These compounds can help you maintain optimal health by reducing inflammation, fighting cancer cells, and protecting the lining of your gut. Cruciferous vegetables may also help prevent certain types of estrogen-dependent cancers, like breast cancer, although this is an area that needs further research. If you want to reap these benefits, then add more cruciferous vegetables to your diet. With so many cruciferous options, you’ll never get bored. Here are some ways to include more crucifers in your diet:
Enjoy a variety of cruciferous vegetables. If you usually eat broccoli, try Bok choy or broccolini.
- Try different recipes that include cruciferous vegetables. Check recipe sites and Pinterest boards for inspiration.
- Roast cruciferous vegetables to caramelize and bring out their sweetness
- Stir fry a variety of vegetables (including cruciferous ones) with your favorite protein
- Choose raw over cooked when possible — raw broccoli has about twice as much vitamin C as cooked broccoli does.
- Flavor foods with mustard, wasabi, and horseradish sauce. These condiments are concentrated sources of glucosinolates that you convert to indoles during chewing and digestion.
Enjoy a variety of fruits and vegetables and don’t forget to eat your broccoli. But also add other cruciferous veggies to your diet for variety. There are lots to choose from!
References:
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- Guerra AS, Malta DJ, Laranjeira LP, Maia MB, Colaço NC, de Lima Mdo C, Galdino SL, Pitta Ida R, Gonçalves-Silva T. Anti-inflammatory and antinociceptive activities of indole-imidazolidine derivatives. Int Immunopharmacol. 2011 Nov;11(11):1816-22. doi: 10.1016/j.intimp.2011.07.010. Epub 2011 Aug 17. PMID: 21855654.
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- Miller AB, Choi BC, Howe GR, Burch JD, Sherman GJ. Epidemiological assessment of risk to humans from exposure to nitrosamines. IARC Sci Publ. 1984;(57):929-36. PMID: 6533077.
- Auborn KJ, Fan S, Rosen EM, Goodwin L, Chandraskaren A, Williams DE, Chen D, Carter TH. Indole-3-carbinol is a negative regulator of estrogen. J Nutr. 2003 Jul;133(7 Suppl):2470S-2475S. doi: 10.1093/jn/133.7.2470s. PMID: 12840226.
- Alon Cna’ani, Merav Seifan, Vered Tzin. Indole is an essential molecule for plant interactions with herbivores and pollinators. ResearchGate. Published March 7, 2018. Accessed July 28, 2022. https://www.researchgate.net/publication/323737971_Indole_is_an_essential_molecule_for_plant_interactions_with_herbivores_and_pollinators
- Beaumont M, Neyrinck AM, Olivares M, Rodriguez J, de Rocca Serra A, Roumain M, Bindels LB, Cani PD, Evenepoel P, Muccioli GG, Demoulin JB, Delzenne NM. The gut microbiota metabolite indole alleviates liver inflammation in mice. FASEB J. 2018 Jun 15;32(12):fj201800544. doi: 10.1096/fj.201800544. Epub ahead of print. PMID: 29906245; PMCID: PMC6219839.Related Articles By Cathe:
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