I love broccoli. My mother ate a ton of it while pregnant with all three kids and we were all born loving broccoli. My father? Not so much – call it too much of a good thing. If I have done one thing right in my life, it was eating broccoli. This was a good thing for a person like me, who suffered from endometriosis. Broccoli contains phytochemicals that help the liver remove estrogen from the body and may help protect against cancer.

However, up until now, I have always been told that it had to be raw to be of benefit and perhaps the lesson here is to not listen to what you are told. Let me be clear – I love cooked broccoli. I do not like raw broccoli at all. I knew in my heart that the cooked broccoli I loved, was indeed good for me. And I was right.

You can chalk this up to people not knowing what they don’t know. And this is just one of many “facts” that people believe that turn out to not be facts at all as new research increases our understanding.

Broccoli and other members of the cruciferous vegetable family such as cabbage, cauliflower, kale, bok choy and Brussel sprouts contains chemicals known as isothiocynates. These chemicals help remove excess estrogen, which is important for women who suffer from estrogen dominant conditions such as endometreosis, fibroids, cysts or PMS and for men who suffer from prostate issues and male andropause, which both have an excess estrogen component.

These amazing chemicals can help decrease inflammation, help induce cell death for cancer cells and help remove carcinogens from the body. However, in order to get these benefits, the phytochemicals need to be converted by an enzyme known as myrosinase which is bound to the isothiocynates.

When we chew the food, the isothiocynates are released. The more we chew, the more the isothiocynates are available to help. When we cook cruciferous vegetables, the myrosinase is deactivated. So this would seem to favour raw broccoli.

But that is not the end of the story. Researchers have found a relationship between our gut bacteria and our ability to benefit from isothiocynates when the food has been cooked. In examining urine and poop, they found that some people retrieve high amounts of isothiocynates from their food and some people do not. Now they are trying to discover the types of bacteria involved.

The means gut bacteria composition counts. And a healthier gut will help those of us, who like our broccoli cooked, to get the benefit from the food.  Also, since I was raised on broccoli and consumed a lot of it before the age of two, when my gut microbes were developing, I am more than likely a good retriever of isothiocynates.

So what can you do?

  • If you eat raw broccoli, chew it well. However, do not consume too much. Free isothiocynates, no longer attached to myrosinase, have been linked to gastrointestinal issues including nausea, vomiting and gastritis.
  • Eat the food and not the sprouts. Researchers found that people who ate broccoli sprouts did not have a significant amount of isothiocynates in their urine which means that they were not available to the body. This makes sense as they would develop as the plant grows into the adult plant.
  • Sauerkraut and kimchi, as fermented foods which contain cabbage, already have bioactive isothiocynates that are ready to rock.
  • Consume your cooked cruciferous vegetables with fermented foods. My favourite is to mix full-fat yogurt or kefir with some melted butter, garlic, lemon and fresh dill (and a little sea salt and pepper) as a sauce for my broccoli.
  • And finally, do whatever you can to support your gut health. We are going to be learning so much more about how our gut bacteria helps us get the most from out food so we might as well start to support it now.

How much should you consume to get the protective benefits? Depending on the which cruciferous vegetables, the amount will vary from 1-2 cups daily according to studies.

Do you have a favourite way of eating your cruciferous vegetables? Please let us know in the comments.

Here is one of mine: Broccoli Cheddar Soup

PS: You may have heard of I3C (indole -3 -carbinol) and DIM (3,3′-diindolylmethane) or seen them as ingredients in supplements for liver or for hormone health. They are often given credit for the reason cruciferous vegetables have anti-estrogen and anti-cancer properties. They are created when isothiocyanates are broken down into non-sulfur compounds. This happens first with by having stomach acid act on the  isothiocyanates and then the process is finished in the intestines by our gut microbes.


Shapiro TA, Fahey JW, Wade KL, Stephenson KK, Talalay P. Chemoprotective glucosinolates and isothiocyanates of broccoli sprouts: Metabolism and excretion in humans. Cancer Epidemiology, Biomarkers, & Prevention. 2001;10(5):501–508

Li F, Hullar MA, Beresford SA, Lampe JW. Variation of glucoraphanin metabolism in vivo and ex vivo by human gut bacteria. British Journal of Nutrition. 2011;106(3):408–416