Ultra-processed foods increasingly linked to high cancer risk

CANCER DIGEST – Feb. 7, 2023 – A dietary study of 200,000 people between the ages of 40 and 69 over a three year period shows a link between ultra-processed foods and cancers of all types, but especially ovarian and brain cancer.

The study by the UK’s Imperial College School of Public Health is based on 24 hour dietary recall questionnaires participants filled out between 2009 and 2012, and were then followed until Jan. 31, 2021. Foods consumed were categorized according to the degree of processing using the NOVA food classification system.

Ultra-processed foods include convenience pre-cooked and instant meals that are also high in added sugars and low in fiber. These foods are also generally higher in salt, fat, sugar, and contain artificial additives. The study was published online in the Jan. 31, 2023 journal eClinical Medicine, a publication of The Lancet.

During a median follow-up of 9.8 years, 15,921 of the participants developed cancer and 4,009 died of cancer. The researchers then analyzed the cancers that occurred along with the dietary data gathered.

The researchers found that higher consumption of ultra-processed foods was linked to greater risk of cancer overall, and specifically ovarian and brain cancers. For every 10 percent increase in consumption of such foods there was a 2 percent increase in the incidence of cancer overall and a 19 percent increase in the incidence of ovarian cancer.

In addition, for every 10 percent increase in consumption of ultra-processed food in a person’s diet there was a 6 percent increase in cancer mortality, and 16 percent increase in breast cancer mortality and a 30 percent increase in ovarian cancer death.

These increases in incidence and death remained the same after the researchers adjusted for a number of socio-economic, behavioral and dietary factors, such as smoking physical activity and body mass index.

“The average person in the UK consumes more than half of their daily energy intake from ultra-processed foods, Dr Kiara Chang, first author for the study said in a press release. "This is exceptionally high and concerning as ultra-processed foods are produced with industrially derived ingredients and often use food additives to adjust color, flavor, consistency, texture, or extend shelf life."

The study aligns with other studies linking ultra-processed foods to cancers and other diseases, including an Aug. 2021 analysis of diet data taken from 159,907 people in the long-running Nurses Health Study and the Health Professional Follow-up Study, which found a 29 percent increased risk of colorectal cancer among men who consumed high amounts of ultra-processed foods.

Sources: Imperial College of Medicine London press release by Conrad Duncan and eClinical Medicine