It seems obvious that healthy eating and cancer prevention go hand in hand, but where is the definite link?
The most relevant and well-researched connection is obesity. Many studies have exemplified that fast food restaurants have a large impact on the prevalence of obesity and contribute largely to weight gain. One study regarding 3 million children found that among ninth graders, a fast food restaurant within .1 miles of a school yielded a 5.2% increase in obesity rate.
Obesity is associated with increased risks in esophageal, pancreatic, breast, colon, endometrium, kidney, thyroid and gallbladder cancer. According to a study using NCI SEER data, in 2007, 4% of cancer cases in men and 7% in women were due to obesity. Depending on the cancer, the percentage of cases attributed to obesity was as high as 40%.
There are several scientific causes behind this link. Fat tissue produces excess amounts of estrogen, as well as other hormones, called adipokines, that can stimulate or inhibit cell growth- leading to the development of tumors. Obese people are often found to have increased levels of insulin which may promote the development of certain tumors. While eating healthy is not a cure-all for obesity, it is a necessary step and a good start towards cancer prevention.
There are several vitamins and compounds found in healthy foods that are linked with cancer prevention. Antioxidants, such as vitamin C, vitamin E, vitamin A and phytochemicals, or chemicals found in plants, help protect against tissue damage resulting from the body’s normal metabolism. Free radicals are naturally formed by the body, but at high concentrations can damage major cell components, such as DNA, proteins and cell membranes, which may play a role in the development of cancer. Antioxidants interact and neutralize these free radicals.
Cruciferous vegetables, such as cauliflower, broccoli, cabbage and brussel sprouts are broken down by the body to form several biologically active compounds that have been been associated with anticancer effects. Two types of compounds in particular, indoles and isothiocyanates, have been shown to inhibit the development of bladder, breast, colon, liver, lung and stomach cancer in rats and mice.
Overall, diets that are found to be high in vegetables, fruits, whole grains, fish and low fat dairy products have been shown to be linked to a lower risk for cancer.
“Antioxidants and Cancer Prevention.” National Cancer Institute. 16 Jan. 2014. Web. 7 Oct. 2015.
“Common Questions about Diet and Cancer.” American Cancer Society. 9 Apr. 2015. Web. 7 Oct. 2015.
“Cruciferous Vegetables and Cancer Prevention.” National Cancer Institute. 7 Jun. 2012. Web. 7 Oct. 2015.
Currie, Janet, Stefano Dellavigna, Enrico Moretti, and Vikram Pathania. “The Effect of Fast Food Restaurants on Obesity and Weight Gain.”American Economic Journal: Economic Policy 2 (2010): 32-63. Print.
“Obesity and Cancer Risk.” National Cancer Institute. 3 Jan. 2012. Web. 6 Oct. 2015.