Eating more ultra-processed foods (UPFs) may be associated with a higher risk of developing cancers of the upper aerodigestive tract (including the mouth, throat and oesophagus), according to a new study.

Researchers from the University of Bristol and the International Agency for Research on Cancer (IARC) analysed diet and lifestyle data on 450,111 adults who were followed for approximately 14 years.

Their findings, published in the European Journal of Nutrition, showed that obesity associated with the consumption of UPFs may not be the only factor to blame for developing cancers.

It showed that eating 10 per cent more UPFs is associated with a 23 per cent higher risk of head and neck cancer and a 24 per cent higher risk of oesophagal adenocarcinoma in EPIC.

Increased body fat only explained a small proportion of the statistical association between UPF consumption and the risk of these upper-aerodigestive tract cancers.

"UPFs have been associated with excess weight and increased body fat in several observational studies. This makes sense, as they are generally tasty, convenient and cheap, favouring the consumption of large portions and an excessive number of calories. However, it was interesting that in our study the link between eating UPFs and upper-aerodigestive tract cancer didn't seem to be greatly explained by body mass index and waist-to-hip ratio," said lead author Fernanda Morales-Berstein, a Wellcome Trust student at the University of Bristol.

The authors suggest that other mechanisms could explain the association. For example, additives including emulsifiers and artificial sweeteners which have been previously associated with disease risk, and contaminants from food packaging and the manufacturing process, may partly explain the link between UPF consumption and upper-aerodigestive tract cancer in this study.

However, the team did add caution regarding 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 increased risk of accidental deaths, which is highly unlikely to be causal.

Further research is needed to identify other mechanisms, such as food additives and contaminants, which may explain the links observed.

However, based on the finding that body fat did not greatly explain the link between UPF consumption and upper-aerodigestive tract cancer risk in this study, Morales-Berstein, said, "Focusing solely on weight loss treatment, such as Semaglutide, is unlikely to greatly contribute to the prevention of upper-aerodigestive tract cancers related to eating UPFs."