Updated: Jan 9
Broccoli (Brassica oleracea var. Italica): A powerhouse vegetable, loved by some, loved to be hated by many. Broccoli is part of the cruciferous or Brassicaceae family (along with Brussel sprouts, cauliflower, cabbage, kale, bok choy and more). Loaded with vitamins, minerals, and fiber, it's no wonder why broccoli and other cruciferous vegetables are so beneficial, however, what really defines and makes these vegetables stand out are the sulfur-containing compounds responsible for not only the bitter flavor and pungent aroma, but gives them powerful anticancer, detoxification and alkalizing effects. Recent epidemiological studies suggest that specifically cruciferous vegetables offer more health benefits than any other vegetable.
When I was a kid, my parents would threaten to replace our fun plans with going to the "broccoli factory" if we misbehaved. This was more than enough to keep my behavior in check because the broccoli factory sounded miserable! Well, jokes' on them now- I bet they didn't expect me to become a nutritionist and actually WISH I could go to a broccoli factory!
Other key compounds found in Broccoli:
Vitamin C, Vitamin E, quercetin, kaempferol glycosides, glucosinolates (Glucobrassicin and glucoraphanin).
**Here we will focus mostly on the beneficial effects of glucosinolates.
Nutritional Properties and Science-y Stuff
- Glucorap is a cross between broccoli and Chinese kale with similar nutritional properties as broccoli.
Broccoli contains glucoraphanin, which is a precursor to the production of sulforaphane in the body. Sulforaphane is a pretty spectacular compound, as it upregulates phase II detoxification, as well as inhibits cancer cell production, and can protect against inflammation.
Contrary to popular belief, detoxification is not the abstinence of food, rather, detoxification requires many nutrients to work properly.
There are three phases of detoxification:
- Phase I - Toxins are generally stored in fat cells or in other forms less harmful to the body. I order to remove these toxins, they must be liberated and set free in the body.
- Phase II - modifies the toxins to by binding substances to help prepare them for elimination.
- Phase III - elimination, mostly through breath, sweat, and urine.
Broccoli and other brassica vegetables increase Phase II glucuronidation, which is specifically involved in the clearance of endogenous compounds (things inside your body, like old hormones, and used up digestive compounds like bilirubin). Sulforaphane has also been linked to the detoxification of heavy metals, like arsenic and mercury that may accumulate in the body from the environment or poor quality processed food and meat/fish (Crinnion & Pizzorno, 2018; Jeffery & Araya, 2009). Interestingly, mustard seed has been shown to increase the bioavailability of sulforaphane in broccoli, so it is a good option to season with when preparing broccoli to support detoxification (Okunade, et al., 2018).
Protects against Cancer:
Because of the increased ability to rid toxins, both environmental and endogenous, sulforaphane is considered a powerful anti-cancer agent and has been associated with reduced cancer risk. For example, sulforaphane has been seen to affect DNA transcription to upregulated apoptosis (cell death) and suppress proliferation of human liver cancer cells (Dos Santos, et al., 2020) It also may increase efficiency of some chemotherapy drugs in breast cancer and as well as have cardioprotective properties in chemo treatment (Bose, et al., 2018). These are just a few examples of the powerful effects sulforaphane may have on cancer, as there is extensive research on this topic (National Cancer Institute, 2012). It should be noted, however, despite the high concentration of sulforaphane, it is not and should not be considered the sole means of targeting cancer. Please consult your healthcare provider.
- Glucobrassicin / Indole-3-carbinol (I3C)
Glucobrassicin releases bioactive indole-3-carbinol (I3C) which, like sulforaphane has many health benefits, specifically in estrogen metabolism, which may be linked to breast cancer prevention as well as the upregulation of CYP450, which is an important enzyme of the detoxification system (Jeffery & Araya, 2009).
Animal studies suggest that I3C also may positively effect the immune system by increasing regulatory T cells, which in turn improves oral tolerance (food allergies) and immune function in the gut (Hammerschmidt-Kamper, et al., 2017).
The combination of these and many other therapeutic compounds found in broccoli may be more effective when consumed in the diet like broccoli, as opposed to the supplemental form of these separate constituents.
There are many ways to prepare broccoli.
It can be eaten raw, enjoyed with a variety of savory dips, like hummus. Raw vegetables may be difficult to digest for some, causing gastrointestinal discomfort.
Steaming is a great option, as it is a gentle cooking method, allowing the maintenance of nutrients. In fact, research shows that steaming cruciferous vegetables maintains the highest glucosinolate content (sulforaphane and I3C), whereas boiling directly in water retains fewer glucosinolates (Baenas, et al., 2019). Steam fresh or frozen broccoli by bringing a small amount of water (about an inch) to a light boil. Place the broccoli in a steaming basket like this one and cover. Steam for a few minutes, until tender (careful, if you steam too long it will turn to mush, so check often)
Roasting is my favorite way to prepare vegetables. High heat cooking should be used with caution, as it may create byproducts, unhealthy to us, however, roasted broccoli is better than no broccoli! A little oil (olive, or avocado) salt and garlic powder and you can never go wrong. Place in the oven at 425 until tender. Cooking times vary.
Riced veggies are a creative way to add extra nutrients to your meals and cauliflower rice tends to get all the attention. But did you know you can make broccoli rice too?! Toss a head of broccoli (chopped up) into a food processor and pulse until desired consistency is reached; not too long, or else you'll get puree! OR just buy it riced from the store. Can be prepared on the stovetop, in a little bit of olive oil. Heat until tender and remove from heat.
BroccolinBroccoli sprouts are another way to benefit from the wonderful effects of broccoli. Broccoli sprouts are shown to have more glucoraphanin/sulforaphane, while mature broccoli may have more glucobrassicin/I3C. Topping a salad or using it as a garnish on any dish is a fantastic way to add a high concentration of nutrients to your daily diet.
Sprouts- Broccoli sprouts are another way to benefit from the wonderful effects of broccoli. Broccoli sprouts are shown to have more glucoraphanin/sulforaphane, while mature broccoli may have more glucobrassicin/I3C. Topping a salad or using as a garnish on any dish is a fantastic way to add a high concentration of nutrients to your daily diet.
Fresh/Frozen - While frozen may seem inferior to fresh broccoli, many nutritional compounds remain in frozen produce and is a great option when fresh broccoli is not a realistic option.
Here are some of my recipes containing broccoli!
- Low Carb Teriyaki Chicken (coming soon)
Baenas, N., Marhuenda, J., García-Viguera, C., Zafrilla, P., & Moreno, D. A. (2019). Influence of Cooking Methods on Glucosinolates and Isothiocyanates Content in Novel Cruciferous Foods. Foods (Basel, Switzerland), 8(7). Retrieved from: https://www.mdpi.com/2304-8158/8/7/257
Bose, C., Awasthi, S., Sharma, R., Beneš, H., Hauer-Jensen, M., Boerma, M., & Singh, S. P. (2018). Sulforaphane potentiates anticancer effects of doxorubicin and attenuates its cardiotoxicity in a breast cancer model. PLoS ONE, 13(3), 1–22. Retrieved from: https://www.ncbi.nlm.nih.gov/pubmed/29518137
Crinnion, W., & Pizzorno, J. E. (2018). Clinical Environmental Medicine - E-BOOK : Identification and Natural Treatment of Diseases Caused by Common Pollutants. St. Louis, Missouri: Elsevier. Retrieved from e textbook
Dos Santos, P. W. da S., Machado, A. R. T., De Grandis, R. A., Ribeiro, D. L., Tuttis, K., Morselli, M., … Antunes, L. M. G. (2020). Transcriptome and DNA methylation changes modulated by sulforaphane induce cell cycle arrest, apoptosis, DNA damage, and suppression of proliferation in human liver cancer cells.
Food and Chemical Toxicology, Retrieved from: https://www.ncbi.nlm.nih.gov/pubmed/31838189. St. Louis, Missouri: Elsevier. Retrieved from e-textbook
Food and Drug Administration. (2017). Nutrition Information for Raw Vegetables. Retrieved from: https://www.fda.gov/food/food-labeling-nutrition/nutrition-information-raw-vegetables
Hammerschmidt-Kamper, C., Biljes, D., Merches, K., Steiner, I., Daldrup, T., Bol-Schoenmakers, M., … Esser, C. (2017). Indole-3-carbinol, a plant nutrient and AhR-Ligand precursor, supports oral tolerance against OVA and improves peanut allergy symptoms in mice. PLoS ONE, 12(6), 1–17. Retrieved from: https://www.ncbi.nlm.nih.gov/pubmed/28666018
Jeffery, E. H., & Araya, M. (2009). Physiological effects of broccoli consumption. Phytochemistry Reviews, (1), 283. Retrieved from https://link.springer.com/article/10.1007/s11101-008-9106-4
National Cancer Institute. (2012). Cruciferous Vegetables and Cancer Prevention. National Institutes of Health. Retrieved from: https://www.cancer.gov/about-cancer/causes-prevention/risk/diet/cruciferous-vegetables-fact-sheet
Okunade, O., Niranjan, K., Ghawi, S. K., Kuhnle, G., & Methven, L. (2018). Supplementation of the Diet by Exogenous Myrosinase via Mustard Seeds to Increase the Bioavailability of Sulforaphane in Healthy Human Subjects after the Consumption of Cooked Broccoli. Molecular Nutrition & Food Research, 62(18), e1700980. Retrieved from: https://onlinelibrary.wiley.com/doi/abs/10.1002/mnfr.201700980