Ultra-Processed Foods and Red Meat May Be Partially to Blame for the Increase in Colorectal Cancer
Article By Kelly Guthrie - March 15, 2023
Take pause before you bite into that hot dog or take a sip of your sugary soda. Research shows that consuming ultra-processed foods increases the risk of colorectal cancer (CRC), cancer of the bowel, colon, or rectum. Studies continue to reveal that the Western diet is partially responsible for the increasing incidence of CRC. What is the connection and how can we change our dietary habits?
Not including some forms of skin cancer, CRC is the fourth most common cancer in the U.S., and the incidence in younger adults is on the rise. While there are several risk factors for this life-threatening disease, including family history and genetic syndromes, this National Nutrition Month, we will examine the link between diet and CRC risk.
A recent study by a team led by researchers at the Tufts University and Harvard University published in The BMJ indicated that men who consumed high rates of ultra-processed foods were at 29 percent higher risk for developing CRC than men who consumed smaller amounts. They did not find the same association in women.
Researchers found a strong link between ultra-processed ready-to-eat meat, poultry, or fish-based products. Higher consumption of sugar-sweetened, fruit-based, and sugary milk-based beverages was also associated with an increased risk of CRC.
Ultra-processed foods like hot dogs, packaged sweet snacks, and cereals have added colors, fats, and preservatives and they are usually higher in sodium, fat, added sugar, and calories. Unfortunately, according to a recent study published in The American Journal of Clinical Nutrition, ultra-processed foods now contribute to 57 percent of total daily calories consumed by American adults.
Research over the past couple of decades has indicated a link between CRC and red or processed meats. Processed meats like bacon and deli meats are those that are smoked, cured, salted, fermented, or preserved with added chemicals for better color and shelf life. More study will need to be done on this connection, but it is commonly thought that some of the preservatives in the meat are responsible. A 2021 study out of the Harvard T.H. Chan School of Public Health discovered a pattern of DNA damage in the colorectal tumors of those who reported having diets higher in red and processed meats. Another consideration is the high heat we use to cook these meats could be producing cancer-causing compounds.
An American Institute for Cancer Research (AICR) report echoes these findings:
Every 50 grams of processed meat consumed daily, which is about one hot dog, is linked to a 16 percent increase in colorectal cancer.
Regularly eating high amounts of red meat (more than 18 ounces, cooked, weekly) increases colorectal cancer risk.
With this in mind, what diet is best and how do we break unhealthy eating patterns? My OHC colleagues and I always promote a heart-healthy diet, and there is evidence that a plant-based diet is associated with a lower CRC risk. Eating a plant-based diet means that at least two-thirds of what you consume is plants (vegetables, whole grains, beans, fruits, and plant-based proteins like tofu). Whole foods (unprocessed foods) and fiber-rich foods lower the risk of colon polyps which have the potential to become cancerous. According to the AICR report, eating approximately three servings of whole grains daily reduces the risk of colorectal cancer by 17 percent.
This article provides convincing evidence to limit consumption of ultra-processed foods and red meat, but it can be challenging to change longtime eating habits. For tips, read OHC radiation oncologist John F. Sacco’s article in OHC’s winter/spring 2022 newsletter. Try to make gradual dietary changes. For example, if you eat red meat four times a week, reduce that to three times a week, then two, etc.
It is important to note that a healthy plant-based diet can help prevent several cancer types in both men and women. If you need assistance adjusting your eating habits, talk to your healthcare provider who may recommend a consultation with a registered dietician.