Thursday, October 20, 2016

Brassicas to Fight Cancer

Baby Bok Choi
By Laurel Blomquist

     Welcome to another article in the anti-cancer series. This anti-cancer diet also combats neurological, immunological, gastrointestinal, cardiovascular and metabolic disorders, as well as the process of aging. It’s pretty amazing that we can heal ourselves by making healthy food choices. Today we’re going to dive into the brassica family, commonly known as cole crops. Except where noted, all references are from Foods to Fight Cancer.
     The Brassica Family is one of the most represented on any CSA Farm, and with good reason. This large family includes broccoli, cauliflower, romanesco, broccoli raab, kales, collards, arugula, radishes, turnips, rutabaga, cabbages, Brussels sprouts, kohlrabi, mustards and bok choy to name a few. Cabbage is probably the oldest cultivated vegetable, dating to at least 6,000 years ago (p. 69). Ancient peoples must have indeed revered it, because most of the varieties we eat have been cultivated through selective breeding from one species of wild cabbage. Hippocrates,circa 400 BC, called it “the vegetable of a thousand virtues” (p. 71). Marcus Porcius Cato, circa 200 BC, held cabbage as a universal remedy against sickness and a virtual fountain of youth. He wrote in De Agri Cultura, On Farming, “Eaten raw with vinegar, or cooked in oil or other fat, cabbage gets rid of all and heals all.” (p. 72).  He recommended cabbage for hangovers, and even used it as a poultice to treat cancerous ulcers. 
     Modern medicine has proven time and again that brassicas have a preventative effect on cancers of the bladder, breast, lung, stomach, colon, rectum, and prostate (p. 72). Brassicas contain the largest variety of phytochemical compounds with anticancer activity. Just what makes them so powerful?
     One such molecule is called a glucosinolate. You have probably tasted them without knowing it; they are responsible for the slightly bitter or pungent flavor that these vegetables tend to have. Glucosinolates are stored in the molecules of a brassica vegetable until it is chewed, chopped or cooked. As the cell walls break down, glucosinolates mix with myrosinase, an enzyme. Upon mixing with the enzyme, glucosinolates are converted to isothiocyanates. These molecules are what fight cancer directly (p. 73). In broccoli, for example, the isothiocyanate is called sulforaphane. This sulfur molecule is what you smell when you overcook broccoli. 
     In order to get the full benefit of the isothiocyanates, there are a few things to keep in mind. Glucosinolates are very soluble in water, and myrosinase is sensitive to heat. The authors suggest that briefly steaming brassicas, stir frying or eating them raw are the best ways to preserve these compounds, as opposed to boiling (p. 74). Of course, these methods will also preserve the bright green (or red) color of the vegetable and have the added bonus of tasting better. The practice of blanching and freezing brassicas as a way of preserving them is actually not recommended if you want to retain these beneficial molecules. Because of the heat and amount of water involved with this process, the amount of bioavailable glucosinolates is reduced and the myrosinase enzyme is denatured. If you absolutely must boil your broccoli, I would recommend a soup as the soup base may retain more of the benefits. 
     Different glucosinolates are found in different brassicas, producing different isothiocyanates which have varying amounts of anti-cancer properties. Sulforaphane in broccoli is one of the most powerful. One serving of broccoli contains about 60 mg of sulforaphane, and one serving of broccoli sprouts contains 600 mg (p. 75)! Personally, I started making my own broccoli sprouts, from organic seed, of course, and adding them to my daily salad when I learned this information. Sprouts are very easy to make in your kitchen, and a nice addition to your winter menu when fresh, local broccoli is not available. 
     Sulforaphane increases your body’s ability to remove toxins linked to cancer. This reduces the occurrence, number, and size of tumors. Sulforaphane also directly attacks cancerous cells, triggering apoptosis, or cell death (p. 75). Sulforaphane also has antibiotic and antibacterial properties, particularly against Helicobacter pylori, which causes gastric ulcers. Exposure to this bacteria and resulting ulcers will increase your chances of stomach cancer 3-6 times over (p. 76).
     Of course, broccoli is hardly the only brassica with beneficial molecules. Watercress and Chinese cabbage contain phenethyl isothiocyanate, or PEITC, which protects against esophageal, stomach, colon, and lung cancers. PEITC also directly attacks leukemia, colon, and prostate tumors through apoptosis (p. 76).
     Brussels sprouts and our hero broccoli also contain indole-3-carbinol, or I3C. Actually, most brassicas contain at least some I3C, but these two have it in the largest amounts. I3C causes modifications in estradiol, which in turn reduces the ability of estrogen to promote cell growth in the breast, cervix, and uterus, thereby preventing cancer in those tissues (p. 77).
Baby Kale Mix
     We should not forget about kale and collards, which have had a popularity resurgence in recent years. Kale production rose 60% between 2007 and 2012 according to the USDA (Martin), and collards are picking up the slack, since demand for kale has overtaken supply (Krogh). In addition to containing beneficial isothiocyanates, they are good sources of iron, folic acid and Vitamins A and C. 
     The doctors recommend 3-4 weekly servings of brassicas to reap their medicinal benefits. Harmony Valley Farm has done our part this season (and every season) to make sure you are getting your RDA of brassicas. So far this season, you have received brassicas every week except one, and sometimes received 4 varieties in one week! You have received sauté mix, baby arugula and baby kale, watercress, hon tsai tai, kohlrabi, baby bok choi, cauliflower, cabbage, baby white turnips, bunched kale, green top spring radishes and broccoli no less than 9 times, possibly more if you got it as a bonus item. In total, we’ve delivered 53 brassica selections over the course of the past 25 weeks, most of which amount to 3-4 servings each, and the season’s not over yet! Frost doesn’t stop brassicas, in fact it sweetens them, so we can enjoy these all the way to the end of the growing season. To your health!

Beliveau, Richard, and Denis Gingras. Foods to Fight Cancer. 2007
Krogh, Josie. “Popularity of Collards Reaching Beyond the South.” April 19, 2015. 
Martin, Andrew. “Boom Times for Farmers in the United States of Kale.” May 9, 2014. 

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