by Eating more ultra-processed foods (UPF) may be associated with a higher risk of developing cancers of the upper aerodigestive tract (including mouth, throat and oesophagus), according to a new study led by researchers at the University of Bristol and the International Agency for the Cancer Research (IARC).
The authors of this international study, which analyzed diet and lifestyle data from 450,111 adults who were followed for approximately 14 years, say that obesity associated with UPF consumption may not be the only culprit. The study is published today. [22 Nov] in it European Journal of Nutrition.
Several studies have identified an association between UPF consumption and cancer, including a recent study that looked at the association between UPF and 34 different cancer types in Europe’s largest cohort study, the European Prospective Investigation into Cancer cohort. and Nutrition (EPIC).
As more evidence emerges about associations between UPF consumption and adverse health outcomes, researchers from Bristol Medical School and IARC wanted to explore this further. Since many UPFs have an unhealthy nutritional profile, the team sought to establish whether the association between UPF consumption and head and neck cancer and esophageal adenocarcinoma (a cancer of the esophagus) in EPIC could be explained by an increase in body fat.
The results of the team’s analyzes showed that eating 10% more UPF is associated with a 23% higher risk of head and neck cancer and a 24% higher risk of esophageal adenocarcinoma in EPIC. Increased body fat only explains a small proportion of the statistical association between UPF consumption and the risk of these upper aerodigestive tract cancers.
Fernanda Morales-Berstein, a Wellcome Trust PhD student at the University of Bristol and lead author of the study, explained: “UPFs have been associated with excess weight and increased body fat in several observational studies. This makes sense, since they are generally tasty, convenient and cheap, encouraging the consumption of large portions and an excessive number of calories. “However, it was interesting that in our study the link between UPF consumption and upper aerodigestive tract cancer did not appear to be largely explained by body mass index and waist-to-hip ratio.”
The authors suggest that other mechanisms could explain the association. For example, additives, including emulsifiers and artificial sweeteners that have previously been associated with disease risk, and contaminants from food packaging and the manufacturing process, may partly explain the link between UPF consumption and cancer of the upper aerodigestive tract in this study.
However, Fernanda Morales-Berstein and her colleagues added caution to their findings and suggested that the associations between UPF consumption and upper aerodigestive tract cancers found in the study could be affected by certain types of bias. This would explain why they found evidence of an association between higher UPF consumption and a higher risk of accidental death, which is very unlikely to be causal.
George Davey Smith, professor of clinical epidemiology and director of the MRC Integrative Epidemiology Unit at the University of Bristol, and co-author of the paper, said: “UPFs are clearly associated with many adverse health outcomes, but do they actually cause them? , or whether underlying factors such as general health-related behaviors and socioeconomic position are responsible for the link, remains unclear, as the association with accidental deaths draws attention.”
Inge Huybrechts, head of the IARC lifestyle exposures and interventions team, added: “Cohorts with long-term follow-up assessments of dietary intake, also taking into account contemporary consumption patterns, are needed to replicate the results. findings of this study, as were the EPIC dietary data.” collected in the 1990s, when UPF consumption was still relatively low. “As such associations may potentially be stronger in cohorts that include recent dietary follow-up assessments.”
More research is needed to identify other mechanisms, such as food additives and contaminants, that may explain the observed links.
However, based on the finding that body fat did not largely explain the link between UPF consumption and upper aerodigestive tract cancer risk in this study, Fernanda Morales-Berstein suggested: “It is unlikely that a focus only in weight loss treatment, such as semaglutide. contribute greatly to the prevention of cancers of the upper aerodigestive tract related to the consumption of UPF.”
Dr Helen Croker, Deputy Director of Research and Policy at the World Cancer Research Fund, added: “This study adds to a growing body of evidence suggesting a link between UPF and cancer risk. The association between higher UPF consumption and an increased risk of developing upper aerodigestive tract cancer supports our Cancer Prevention Recommendations of eating a healthy diet rich in whole grains, vegetables, fruits and beans.”
The study was funded by the Wellcome Trust; Cancer Research UK; International Cancer Research Fund; National Cancer Institute; Horizon 2020 Study ‘Dynamic longitudinal trajectories of the exposome in non-communicable cardiovascular and metabolic diseases’; University of Bristol Vice-Chancellor’s Scholarship; British Heart Foundation and the Medical Research Council.
Paper
‘Ultra-processed foods, adiposity and risk of head and neck cancer and esophageal adenocarcinoma in the European Prospective Investigation into Cancer and Nutrition study: a mediation analysis’ by F. Morales-Berstein et al. in it European Journal of Nutrition.
More information
About ultra-processed foods
Ultra-processed foods (UPF) are complexly manufactured industrial formulations using ingredients not normally found in kitchens (e.g., maltodextrin, hydrogenated oils, modified starches) and cosmetic additives (e.g., emulsifiers, flavourings, colourings, artificial sweeteners). They are generally cheap, very tasty and widely available ready-to-eat products. As a result, they often replace more nutritious, unprocessed or minimally processed foods in the diet.
