EAT THE RAINBOW: GLUCOSINOLATES
- September 6, 2015
If you’ve ever had a really big serving of wasabi, it’s fairly likely that you’d remember the effect it had on your nose and sinuses!
The characteristically pungent taste of wasabi, horseradish and mustard plant comes from a group of phytonutrients called glucosinolates. These are also responsible for the bitterness of cruciferous vegetables (which is where they’re primarily found), although the green colour of vegetables comes from chlorophyll and carotenoids, which are other groups of phytonutrients.
We’ve already seen the health benefits associated with green vegetables because of carotenoids; now, we’re going to explore the many ways in which glucosinolates add their own!
Glucosinolates and Cancer
Glucosinolates enter the body and get broken down by plant enzymes into powerful compounds – these are believed to be the main reason horseradish and cruciferous vegetables are said to have cancer-preventive properties.1
The compounds prevent cancer by two main methods:
1] They increase the enzymes that get rid of toxins in the body.
2] They stop the formation of harmful substances through pollutants that enter the body. For example, they are particularly good against those in tobacco smoke.3
Interestingly, these cancer-preventative benefits are the most prevalent in the parts of the body where the products of glucosinolate-breakdown appear the most (for those who eat a diet rich in cruciferous vegetables).
One example is the gut, where the “good” bacteria also convert glucosinolates into isothiocyanate, which is believed to be the most health-promoting breakdown product of glucosinolates.4
Glucosinolate-breakdown compounds can also be used to treat conditions like abnormal growth on the surface of the cervix and tumors in the respiratory tract, which are related to the human papillomavirus (HPV). This virus is infamous for causing uterine cancer.5
Glucosinolates and Day-to-Day Use
Ever heard of people using cabbage and mustard on wounds, to stop them from being infected by bacteria? The antibacterial (bacteria fighting) activities of glucosinolate compounds have been recognized for many decades against several bacteria! These include E. coli (food poisoning) and Salmonella typhimurium (gastroenteritis).6
Glucosinolate compounds can also deter Candida species fungi, which cause most fungal infections in humans.6
Horseradish root has 10 times more glucosinolates than other vegetables! Juice extracted from it has been used effectively to relieve congestion and sinus discomfort. Its extract is also used as a rubefacient, a heat-producing substance that works like a balm to relieve muscular aches and pains, and painful arthritic joints. It does so by stimulating blood-flow just below and to the surface of the skin.7, 8
There have also been a few reports that the compounds formed from glucosinolates have anti-inflammatory properties, which can be beneficial for a variety of conditions – everything from skin problems to cancer. But the mechanism of how this happens is yet not fully understood.2
Glucosinolates and Cooking
Prolonged cooking doesn’t affect glucosinolates themselves, but can deactivate the enzymes that lead to glucosinolate-breakdown. You know how beneficial the products of the breakdown are, so it’s easy to see why experts recommended that we only lightly cook our greens.4, 9
In fact, lightly steamed greens may even be better than raw greens because this could possibly increase the breakdown of glucosinolates to isothiocyanate. It’s also best to stick to lightly steaming because boiling the greens could make their glucosinolates leach out into the water.4
Now that you know how to best prepare green vegetables for all the amazing health benefits of glucosinolates, go on and get your fill of at least two and a half cups a day!
1. Mithen RF, et al. Journal of the Science of Food and Agriculture 2000, 80(7): 967-984.
2. Wagner AE, et al. Oxidative Medicine and Cellular Longevity 2013, 2013: 964539.
3. Johnson IT. Phytochemistry Reviews 2002, 1(2): 183-188.
4. Traka M & Mithen R. Phytochemistry Reviews 2009, 8(1): 269-282.
5. Higdon JV, et al. Pharmacological research : the official journal of the Italian Pharmacological Society 2007, 55(3): 224-236.
6. Fahey JW, et al. Phytochemistry 2001, 56(1): 5-51.
7. Klein S, et al. The Complete Commission E Monographs: Therapeutic Guide to Herbal Medicines. , vol. 1st. American Botanical Council, 1998.
8. LifeExtension. Horseradish: Protection against cancer and more. LifeExtension Magazine. 2009.
9. Li F, et al. The Journal of Nutrition 2009, 139(9): 1685-1691.