Cruciferous vegetables: Cancer crusaders
In 1996, a pivotal study showed that consumption of cruciferous vegetables decreased the risk both of primary and secondary cancers. The article was published in the journal Cancer, Epidemiology, Biomarkers & Prevention. Researchers reviewed 94 studies and came to the conclusion that high consumption of these vegetables is associated with a decreased risk of many cancers. This is most closely linked with lowered risk of lung, stomach, colon and rectal cancer.
According to the National Cancer Institute, the science shows that it is the glucosinolates that provide the cancer fighting ability of this group of wonder foods. They are rich in a large group of sulfur-containing compounds.
These chemicals are responsible for the pungent aroma and bitter flavour of cruciferous vegetables. As we chew and digest the veggies, these chemicals are broken down into biologically active compounds called indoles, thiocyanates and isothiocyanates.
All big words that only scientists can pronounce easily, but the bottom line is that they prevent the growth of cancer cells.
They do this by stimulating the body’s natural antioxidant system by triggering the liver to produce enzymes that block free-radical attack on our DNA.
Glucosinolates are also anti-inflammatory and have anti-bacterial and anti-viral properties.
Other actions include inactivating carcinogens, reprogramming cancer cells to die (apoptosis) and preventing tumour blood vessel formation (angiogenesis) and tumour cell migration (which is needed for metastasis — or the progression of cancer to an incurable stage IV).
Cruciferous vegetables are also rich in many other nutrients, including several carotenoids (beta-carotene, lutein, zeaxanthin); vitamins C, E and K, folate and minerals. They are also an excellent source of fibre.
Many people would be surprised to hear that they are also a good source of protein with between 20 and 50 per cent of their calories coming from protein. Never ask a vegan, “But where do you get your protein?”
Steaming many of these veggies increases their ability to bind to bile acids which is possibly why eating them helps reduce cholesterol levels.
So what are cruciferous veggies?
They are part of the Brassica genus of plants and include the following: arugula, bok choy, broccoli, brussel sprouts, cabbage, cauliflower, collard greens, horseradish, kale, radishes, rutabaga, turnips, watercress and wasabi.
Due to bombardment in the popular media, we all know that kale is good for us – a fact that sends shivers down many a man’s spine when he sees his wife cheerfully preparing a disgustingly green smoothie for his breakfast.
As you can see, the list is long and, as usual, it is always best to eat a variety of foods to maximize health.
It is never a good idea to decide that one or two foods have magical properties and eat giant quantities of them only, at the exclusion of others.
A final big advantage of loading up your plate with these vegetables is that they help with feelings of satiety for a very low calorie count. A cup of broccoli for example, has only 30 calories.
An easy way to get more cruciferous vegetables into your diet this winter is to minimize the meat in your soups or stews and increase the proportion of vegetables.
My personal preference and recommendation, of course, is to stick to completely plant-based soups and stews, which are delicious and welcome body and soul warmers in this prematurely snowy November.