Lung cancer warning for foods which make up ‘half the average diet’ after new study
Ultra-processed foods filled with preservatives, additives and flavor enhancers have been linked to an increased risk of lung cancer.
In the UK and US, more than half of the average diet consists of ultra-processed foods (UPFs) such as ready meals, fast food and fizzy drinks.
A previous BMJ study from 2024 linked UPFs to 32 harmful health effects, including a higher risk of heart disease, cancer, type 2 diabetes, adverse mental health and premature death.
Eating UPFs has been linked to lung cancer, the most common cancer in the world, according to the World Cancer Research Fund.
Researchers behind the study published in the journal Respiratory announced that there were an estimated 2.2 million new cases and 1.8 million deaths from the disease worldwide in 2020. Chest in question.
But researchers say limiting consumption of these foods could help reduce the global impact of the disease.
While there is no precise definition of UPF, these foods often go through multiple stages of processing, contain long lists of additives and preservatives, and are ready to eat or heat.
Researchers used data from the US Prostate, Lung, Colorectal and Ovarian Cancer Screening Trials, which included 155,000 participants ages 55 to 74 who were randomly assigned to a screening or comparison group between November 1993 and July 2001. Cancer diagnoses were tracked through the end of 2009 and cancer deaths through the end of 2018.
A total of 101,732 people (50,187 men and 51,545 women, average age 62 years) were included in the study, who completed a survey on their dietary habits at entry into the trials. Foods were categorized as: unprocessed or minimally processed; containing processed kitchen ingredients; finished; or ultra processed.
Researchers specifically focused on UPFs, which include sour cream as well as cream cheese, ice cream, frozen yogurt, fried foods, bread, baked goods, salty snacks, breakfast cereals, instant noodles, store-bought soups and sauces, margarine, confectionery, soft drinks, sweetened fruit drinks, restaurant/store-bought hamburgers, hot dogs, and pizza.
The three most prominent food types were lunch meat (11 percent), diet or caffeinated soft drinks (just over 7 percent), and decaffeinated soft drinks (about 7 percent).
Participants were followed for 12 years, during which time 1,706 new cases of lung cancer were diagnosed, including 1,473 cases of non-small cell lung cancer (NSCLC) and 233 cases of small cell lung cancer (SCLC).
When potentially influential factors, including smoking and overall diet quality, were taken into account, participants who consumed the most UPF were 41 percent more likely to be diagnosed with lung cancer than those who ate the least.
Overall, they were 37 percent more likely to be diagnosed with NSCLC and 44 percent more likely to be diagnosed with NSCLC.
Because it was an observational study and no definitive conclusion could be drawn about cause and effect, the researchers admit that they could not take smoking intensity into account, which could also have an impact. Dietary information was collected only once, so they could not account for changes over time and the number of cancer diagnoses was small.
However, researchers highlight the low nutritional value of UPFs and the excessive amounts of salt, sugar and fat they contain.
“The increase in UPF consumption may have led to global increases in obesity, cardiovascular disease, metabolic disorders, cancer, and mortality because these foods are confirmed risk factors for such conditions,” the researchers said.
“Industrial processing alters the food matrix, affecting nutrient availability and absorption, while also producing harmful pollutants,” they added, highlighting acrolein, a toxic component of cigarette smoke found in grilled sausages and caramel fudge. They suggested that packaging materials may also play a role.
“You can’t tell from this study that UPFs cause cancer because it’s observational, so we’re looking at associations, not direct effects. But it strengthens the case for taking a closer look at the food environment in which many people live, where UPFs are cheap, convenient and heavily marketed, making them a go-to for many people,” says nutritionist and author Rob Hobson. Take Your Family Life Out of Processsaid Independent.
He suggested making small changes toward a healthier diet rather than “pointing the numbers at individual foods.”
“This might mean cooking more meals from scratch whenever possible, adding more unprocessed foods like vegetables, beans and grains, or simply being more aware of how often UPFs show up in your day,” she said.
“It’s not about being perfect, it’s about balance and understanding how your food choices support or undermine your long-term health.”
