Higher consumption of ultraprocessed foods may be linked to increased cancer burden and mortality, according to a new, UK-based study published by Chang et al in eClinicalMedicine.
Ultraprocessed foods are food items which have been heavily processed during their production—such as fizzy drinks, mass-produced packaged breads, ready meals, and most breakfast cereals. They are often relatively cheap, convenient, and heavily marketed, often as healthy options. However, these foods are also generally higher in salt, fat, and sugar, and also contain artificial additives. It is now well documented that they are linked to a range of poor health outcomes, including obesity, type 2 diabetes, and cardiovascular disease.
In the new study, researchers used UK Biobank records to collect information on the diets of 200,000 participants aged 40 to 69 years. They monitored the participants’ health over a 10-year period, assessing the risk of developing any type of cancer overall, the specific risk of developing 34 types of tumors, as well as the participants’ risk of dying from cancer.
The study found that higher consumption of ultraprocessed foods was associated with a greater risk of developing cancer overall, and specifically, the development of ovarian and brain cancers. It was also associated with an increased risk of cancer mortality, most notably from ovarian and breast cancers.
For every 10% increase in consumption of ultraprocessed food in an individual’s diet, cancer incidence increased by 2% for cancer overall and by 19% for ovarian cancer. Additionally, each 10% increase in ultraprocessed food consumption was associated with a 6% increase in overall cancer mortality, a 16% increase in breast cancer mortality, and a 30% increase in ovarian cancer mortality. These links remained after adjusting for a range of socioeconomic, behavioral, and dietary factors, such as smoking status, physical activity, and body mass index.
“This study adds to the growing evidence that ultraprocessed foods are likely to negatively impact our health, including our risk [of] cancer. Given the high levels of consumption in UK adults and children, this has important implications for future health outcomes,” stressed senior study author Eszter Vamos, PhD, Senior Clinical Lecturer in Public Health Medicine and Deputy Director of the Public Health Policy Evaluation Unit at the Imperial College London School of Public Health. “Although our study cannot prove causation, other available evidence shows that reducing ultraprocessed foods in our diet could provide important health benefits. Further research is needed to confirm these findings and understand the best public health strategies to reduce the widespread presence and harms of ultraprocessed foods in our diet,” she explained. The World Health Organization and the United Nations’ Food and Agriculture Organization have previously recommended restricting ultraprocessed foods as part of a healthy, sustainable diet.
“The average [individual] in the UK consumes more than half of their daily energy intake from ultraprocessed foods. This is exceptionally high and concerning, as ultraprocessed foods are produced with industrially derived ingredients and often use food additives to adjust color, flavor, consistency, texture, or extend shelf life,” noted first study author Kiara Chang, MSc, a National Institute for Health and Care Research research fellow in the Department of Primary Care and Public Health at the Imperial College London School of Public Health. “Our bodies may not react the same way to these ultraprocessed ingredients and additives as they do to fresh and nutritious minimally processed foods. However, ultraprocessed foods are everywhere and highly marketed with cheap prices and attractive packaging to promote consumption. This shows [that] our food environment needs urgent reform to protect the population from ultraprocessed foods,” she underscored.
There are ongoing efforts to reduce ultraprocessed food consumption around the world, with countries such as Brazil, France, and Canada updating their national dietary guidelines with recommendations to limit such foods. Brazil has also banned the marketing of ultraprocessed foods in schools.
“We need clear front-of-pack warning labels for ultraprocessed foods to aid consumer choices,” Dr. Chang added. She concluded: “Lower-income households are particularly vulnerable to these cheap and unhealthy ultraprocessed foods. Minimally processed and freshly prepared meals should be subsidized to ensure [that] everyone has access to healthy, nutritious, and affordable options.”
The researchers noted that their study was observational and did not show a causal relationship between ultraprocessed foods and cancer—and that further studies are needed to establish this link. However, despite the lack of definitive evidence, the implication that consuming ultraprocessed foods may lead to an increased risk of developing cancer has driven researchers to recommend that individuals limit their intake of these types of foods in order to prevent and reduce the modifiable burdens of cancer.
Disclosure: The research in this study was funded by Cancer Research UK and World Cancer Research Fund. For full disclosures of the study authors, visit thelancet.com.The content in this post has not been reviewed by the American Society of Clinical Oncology, Inc. (ASCO®) and does not necessarily reflect the ideas and opinions of ASCO®.