Ultra-processed foods linked to cancer: An interview with Dr. Fang Fang Zhang of Tufts University
Last month, a study published in the medical journal The BMJ (a weekly peer-reviewed medical journal published by the British Medical Association) linked the consumption of ultra-processed foods to a higher risk of colorectal cancer. . Dr. Fang Fang Zhang, a researcher at Tufts University Friedman School of Nutrition Science and Policy, led this project, focusing specifically on the effects of ultra-processed diets on cancer risk through a large cohort study of 28 year.
One of the key findings of his study was that when comparing the highest and lowest quintile of men based on consumption of ultra-processed foods, those who ate more processed foods had a 29% higher risk of developing colorectal cancer. Notably, his study did not have the same results for women. Zhang mentions that this is likely due to women consuming more processed dairy products, which have certain nutritional health benefits. In comparison, men were more likely to consume ultra-processed foods with very little nutritional value.
Colorectal cancer refers to both colon or rectal cancer, depending on where the cancer starts. It is the third most commonly diagnosed cancer in the country, with colon and rectal cancers having average relative survival rates of 64% and 67% at 5 years, respectively. According to the American Cancer Society, there will be more than 100,000 new cases of colon cancer in the United States this year. Common treatments for colorectal cancer currently are surgery and chemotherapy, both of which have the potential to have long-term negative effects on the health of the patient.
Given the severity of this disease, studies such as Dr. Zhang’s that examine how our daily diet can affect our chances of developing colorectal cancer are extremely valuable. While at Tufts, Zhang worked on several projects examining the link between nutrition and cancer risk, conducting large population-based studies in the area of nutritional epidemiology. She also led a population-based project focusing on cancer prevention at the national level through nutrition policies and interventions. We recently had the opportunity to interview Dr. Zhang about his research.
SAMPAN: How did you get involved in research, particularly in the field of nutritional epidemiology?
ZHANG: Nutrition is part of our daily lives, right? We eat food every day and what we eat plays an important role in many outcomes, especially disease outcomes. So for me, I think it’s good for me to find out what are the dietary risk factors that might contribute to the risk of various diseases. Then we can potentially intervene – hopefully to change… what we eat [and] the food industry… [helping to] reduce these food-borne illnesses.
Zhang also mentions how addicted people in the United States are to ultra-processed foods, which make up the majority of many people’s daily calorie intake. It also addresses the nutritional deficiencies of ultra-processed foods.
ZHANG: Ultra-processed foods bring a lot of convenience to life and also help extend the shelf life of foods.… [Food processing has also] helped to improve food availability.… The problem is that we rely too much on these foods. We did a study a while ago trying to look at trends in ultra-processed food consumption among American children, and ⅔ of our kids’ daily calories come from ultra-processed foods. In adult populations, it is about 57 to 58 percent.…A growing number of studies have reported adverse health effects such as obesity, hypertension, and cardiovascular disease.…In the together, ultra-processed foods present certain nutritional issues.… [Ultraprocessed foods are] overall low in dietary fibre,… high in added sugars, high in sodium,… and also high in fat.
SAMPAN: With processed foods being so accessible and given that not all processed foods would have the same impact on health, what are some healthier processed food options that people can find?
ZHANG: The way ultra-processed foods are determined is based on food processing, not necessarily based on nutrients. Some ultra-processed foods might be healthier in their nutrient content, even if they are ultra-processed. An example would be whole grain foods. Whole grain foods might be ultra-processed, but whole grain foods might contain a higher level of fiber, which is a healthy nutrient.… [But] even though whole grain foods are higher in dietary fiber, we can add added sugars to them.… Whole grain foods do not necessarily mean they are healthy foods.… I would say the healthy version of grain foods ultra-processed whole… [have] little or no added sugars, which could be a healthy option.
SAMPAN: Ultra-processed foods are much cheaper and more accessible to people than fresh produce. How might this affect people of lower socioeconomic status?
ZHANG: That’s a problem, I think. We also look at some of the dietary nutrition policies for disease prevention here at the Friedman School of Tufts. I am one of the faculty members working to help assess [what] nutrition policies we can develop [as well as their] cost-effectiveness,… what are the expected benefits, and how many cancer cases are reduced… We are thinking about how to improve nutrition at the population level. Food pricing is a strategy…so we need to think about the possibility of having subsidy policies, providing fresh vegetables and fruits – those unprocessed or minimally processed foods – at a cheaper price, especially for those with a low level of income.… Reflection on how we can help improve the diet of the population, especially the underserved population, where they are at higher risk of cancer, cardiovascular disease and a diet overall poorer.
When asked what research still needs to be done in this area, Zhang said, “We need more studies like this…you need to study a lot of people and follow them for a long time.” She expressed the need for more observational studies, especially those that investigate differences in health outcomes for different population subgroups, as well as studies exploring the mechanism behind the link between colorectal cancer and ultra foods. -transformed. She hopes that greater scientific evidence supporting this link can help inform public policy and nutrition education in the future.
As for what Sampan readers can do to help improve their diet, Zhang recommends cooking with “fresh vegetables and fruits,… fresh meat, poultry, seafood… Dairy products can also be a good option if they don’t contain a lot of added sugar. .” As for what to avoid at the grocery store, Zhang emphasizes “packaged foods, … sugary drinks, … industrial bread and snacks! … Many of them are ultra-processed”.