Sulforaphane

Broccoli, cauliflower, Brussel’s sprouts, cabbage, kale and radishes, among others, are vegetables that belong to the cruciferous vegetable family. You might associate cruciferous vegetables with a distinct pungent aroma or bitter flavor, a combination that is tough to swallow for many individuals. So why would anyone want to consume these vegetables?

Most of us know that cruciferous vegetables contain micronutrients like Vitamin C, Vitamin K, iron, and potassium that are essential to health, but did you know that these vegetables also contain phytochemicals? The phytochemical most studied in cruciferous vegetables, and extensively studied in broccoli, is named SULFORAPHANE. Sulforaphane is the phytochemical responsible for the flavor and aroma of broccoli and is used by the plant as its own natural pesticide. Researchers have discovered, in both animal and human studies, that sulforaphane exhibits chemo preventive properties. Sulforaphane interventions have been studied in breast, lung, gastric, colorectal, prostate, skin, head/ neck, liver cancers and more.

Sulforaphane is not readily available in broccoli but its precursor molecule, glucoraphanin, is found in abundance. Researchers have found that the glucoraphanin in broccoli is converted to sulforaphane by an enzyme called myrosinase that is released from the cell wall after being damaged by biting, chewing, or cutting the plant. In fact, very little sulforaphane exists in the undamaged plant but is produced in appreciable amounts when the cell walls are disrupted and myrosinase is released. It is important to note that because enzymes are protein-derived molecules, heat causes them to unravel (or denature). This means that boiling, roasting, or even steaming broccoli may inhibit the conversion of glucoraphanin to sulforaphane (Clarke et al. 2008). It is also important to note that the sulforaphane that is produced is a very unstable molecule, meaning it breaks down quickly and easily once it is formed. The pharmaceutical, dietary supplement, and nutraceutical industries have been scrambling to put sulforaphane into a pill ever since its discovery. In fact, there are now several U.S. patents related to sulforaphane production methods.

Many of the methods for producing sulforaphane involve the extraction of glucoraphanin from BROCCOLI SPROUTS. It has been shown that young, sprouted broccoli seeds in the order of 3-7 days’ growth contain the highest glucoraphanin levels, and 10 – 100 times more glucoraphanin than mature broccoli (Fahey et al. 1997). So exactly how many sprouts do you have to eat per day to reach the therapeutic dose of sulforaphane? Unfortunately, there is not enough data around whole food broccoli sprout consumption to recommend an exact amount and everyone’s biology is unique, so my recommendation is to eat as much as you can tolerate! Broccoli sprouts are relatively safe to consume and have very few known side effects.

A recent trip to the health food store revealed a jaw dropping $9.00 container of broccoli sprouts! For an even heftier price tag, I found broccoli sprout supplements. I'm not a big fan of most supplements, especially those usually found in grocery stores, but that is a topic for another day. Did you know that you can grow your own broccoli sprouts from sprouting seeds with a mason jar right on your countertop for just pennies a day?

SPROUTING INSTRUCTIONS (1 pint mason jar)

Place 1/2 tablespoon sprouting seeds in jar and replace sprouting lid *make sure jar is sanitized
Fill jar with water and soak seeds 8 hours or overnight
Pour off water, rinse and drain thoroughly, place jar at roughly a 70 degree angle upside down. Be sure air can circulate so that mold and bacteria do not develop
Rinse and repeat several times per day while keeping jar out of direct sunlight
When sprouts begin to appear, continue washing and rinsing procedure daily for 3-5 days with jar in direct sunlight
Rinse one last time and store sprouts refrigerated in an airtight container.

*Sprouts should be fresh for about one week. Rinsing every few days may be helpful.

I love adding broccoli sprouts to avocado toasts and to salads, but you can add them to any sandwich for extra crunch or to smoothies if you find the taste unpleasing. As with all acquired tastes, it may take some time to acquire this taste.

Disclaimer:

Broccoli sprouts are high in fiber so some gastrointestinal issues may arise with consumption, especially with overconsumption.
Broccoli sprouts are high in vitamin K which could possibly interact with blood thinning medications.
Improper handling/ rinsing/ preparing may lead to bacterial or fungal overgrowth and cause illness, especially in the immunocompromised.

References:

Yagishita, Y., Fahey, J. W., Dinkova-Kostova, A. T., & Kensler, T. W. (2019). Broccoli or Sulforaphane: Is It the Source or Dose That Matters?. Molecules (Basel, Switzerland), 24(19), 3593. https://doi-org.proxy.library.ohio.edu/10.3390/molecules24193593

Fahey, J. W., Zhang, Y., & Talalay, P. (1997). Broccoli sprouts: an exceptionally rich source of inducers of enzymes that protect against chemical carcinogens. Proceedings of the National Academy of Sciences of the United States of America, 94(19), 10367–10372. https://doi-org.proxy.library.ohio.edu/10.1073/pnas.94.19.10367

Clarke, J. D., Dashwood, R. H., & Ho, E. (2008). Multi-targeted prevention of cancer by sulforaphane. Cancer letters, 269(2), 291–304. https://doi-org.proxy.library.ohio.edu/10.1016/j.canlet.2008.04.018