More than one hundred years of evidence suggests specific ways in which a diet rich in vegetables may help protect against cancer .
Turns out we’ve known for a good long time that veggies really do a body good. In 1894 the USDA’s first director of research activities published a pamphlet analyzing the eating behaviors of some New Englanders. He concluded that, “we eat too much…fat, starch, and sugar….how much harm is done to our health by our one-sided and excessive diet no one can say. Physicians tell us that it is very great.”
Now, more than one hundred years later, physicians and researchers are saying much the same thing, but with more specificity. Both the American Cancer Society (ACS) and the American Institute of Cancer Research (AICR) have published dietary recommendations that include essential information about the importance of vegetable intake.2,3
Filling up on veggies is especially important for women because being overweight or obese is linked with an increased risk of breast cancer and perhaps other cancers.4 In fact, according to the ACS, “evidence suggests that one third of the more than 500,000 cancer deaths that occur in the United States each year can be attributed to diet and physical activity habits, with another third due to cigarette smoking.”5
Incorporating more vegetables into your diet, along with regular physical activity, is one important step you can take toward prevention and overall wellness.
How Much Is Enough?
Rachel Beller, President and Founder of the Beller Nutritional Institute and former director of nutritional oncology at the John Wayne Cancer Institute, says, “five to eight servings of vegetables is very, very good.” The AICR, in their report, recommends “at least five portions (at least 14 oz) of a variety of non-starchy vegetables and of fruits every day,” (promoting twenty-one ounces as an even better goal). The ACS also recommends five or more servings of a variety of fruit and vegetables each day. They define a serving as 1 cup raw, leafy vegetables; ½ cup other raw or cooked vegetables, chopped; or ¾ cup vegetable juice.6
So how can you make sure that your meals include the recommended daily servings? One way to start eating this many vegetables is to change the way you view your meals: instead of focusing on meat or other protein, put the spotlight on plant-based foods and create your plate from there. Seek out appealing recipes and meal plans that feature vegetables and plant-based proteins as the main course, and be open to new and different foods to add variety to your menus.
As a rule of thumb, red and orange vegetables such as tomatoes, red peppers, butternut squash, and carrots, are high in healthy carotenoids, including beta-carotene and lycopene, which have antioxidants, among other benefits. (Antioxidants help repair the damage done to cells by the body’s metabolic processes.) Green leafy vegetables are great sources high in Vitamin E, another potent antioxidant, and, the AICR report tells us, garlic has sulfites that may inhibit tumor formation and cell growth and may also have antibiotic properties. Spinach, broccoli, and romaine lettuce are loaded with folates, which help DNA synthesis and cell replication.
According to the AICR, there is evidence that folates may protect against pancreatic cancer and carrots could potentially be helpful in protecting against cervical cancer. In addition, allium vegetables, such as garlic and shallots, are also cited in the AICR report as potentially protective against stomach and colorectal cancers.
Once you’ve made the decision to integrate more vegetables into your diet, you should be aware that the way you prepare your meal may have an impact on the nutritional value of your food. For some specific ingredients, some cooking methods can reduce the nutrient content in vegetables, while others convert helpful chemicals so the body can use them more easily. For instance, vegetables containing lycopene, such as tomatoes, will yield more benefit when cooked. And when preparing vegetables containing carotenoids, a combination of cooking, pureeing, and adding oil makes these important nutrients more available. Peeling and chopping garlic and allowing it to stand for 15 to 20 minutes gives you the most benefit; however, heating garlic without peeling it reduces or may eliminate its valuable effects.
Keep It Simple
Many people have a hard time preparing large amounts of vegetables in a way that makes them appetizing enough to ensure that they eat the recommended daily allowance every day. Cardiologist Dr. David Agus recommends looking in the deli section of premium groceries and investigating home delivery services. “New meal delivery services really make it easy for my patients who are too busy or too ill to seek out the right ingredients and cook their own gourmet meals.” These services can deliver nutritionally-specialized meals that contain many of the ingredients that nutritionists recommend. “It can be hard to find pre-cooked meals that offer a healthy dose of cancer-fighting nutrients,” echoes Beller, “and these services can make it easier to ensure you’re getting the nutrients you need.”
1 Nestle, Marion. Food Politics. Berkeley, CA: University of California Press; 2007.
2 Byers T, Nestle M, McTiernan A, et al. American cancer society guidelines on nutrition and physical activity for cancer prevention: reducing the risk of cancer with healthy food choices and physical activity. CA Cancer J Clin. 2002; 52:92. Available at: http://caonline.amcancersoc.org/cgi/content/full/52/2/92#SEC4.
3 World Cancer Research Fund / American Institute for Cancer Research.
Food, Nutrition, Physical Activity, and the Prevention of Cancer: a Global Perspective.
Washington DC: AICR, 2007
4 Calle EE, Rodriguez C, Walker-Thurmond K, Thun MJ. Overweight, obesity, and mortality from cancer in a prospectively studied cohort of US adults. New England Journal of Medicine. 2003;348:1625–1638.
5 Byers T, Nestle M, McTiernan A, et al. American cancer society guidelines on nutrition and physical activity for cancer prevention: reducing the risk of cancer with healthy food choices and physical activity. CA Cancer J Clin. 2002; 52:92. Available at: http://caonline.amcancersoc.org/cgi/content/full/52/2/92#SEC4.
6 American Cancer Society. What’s in a Serving? http://www.cancer.org/docroot/NWS/content/NWS_2_1x_What_s_in_a_Serving_.asp.
Accessed April 2008.