When most people think about lung cancer, smoking is the first thing that comes to mind. And while it remains the biggest risk factor, new research suggests that other lifestyle choices — including what we eat — may also play a role.
A recent study published in the journal Thorax has found that people who consume large amounts of ultra-processed foods may have a higher risk of developing lung cancer. The findings add to growing evidence that diet and lifestyle could influence cancer risk alongside more well-known factors.
The study in question analysed data from over 100,000 adults taking part in the Prostate, Lung, Colorectal and Ovarian Cancer Screening Trial over an average of 12 years.
Participants who reported the highest consumption of ultra-processed foods — including ready meals, sugary drinks, packaged snacks, and processed meats — were around 40% more likely to develop lung cancer than those who consumed the least.
Importantly, this link persisted even after accounting for age, gender, smoking history, physical activity, and overall calorie intake, suggesting that diet may influence lung cancer risk independently of smoking.
What are ultra-processed foods?
These foods come from industrial production and use ingredients rarely found in home cooking. Manufacturers often add preservatives, flavourings, colourings, and other additives. They offer convenience and are easy to buy, but they usually contain high levels of sugar, salt, and unhealthy fats. They also lack fibre, vitamins, and minerals.
Eating lots of ultra-processed foods over many years can trigger chronic inflammation and oxidative stress in the body. Both increase cancer risk. Diets low in nutrients also leave the body short of antioxidants and fibre, which normally protect cells and help them stay healthy.
Some additives and chemicals created during processing may disrupt normal cell activity, although researchers need more evidence to understand how.
Paula Chadwick, Chief Executive of Roy Castle Lung Cancer Foundation, welcomed the study and said it expands our understanding of lung cancer risk.She said:
“It’s important to look beyond smoking when we talk about lung cancer. Lifestyle factors, including diet, could play a part in reducing risk. Understanding these links can help people take steps to protect their health and save lives.”
Reducing your risk
While quitting smoking and reducing exposure to harmful air pollutants remain the most important ways to lower lung cancer risk, paying attention to diet could be another useful step.
Reducing ultra-processed foods and incorporating more whole foods, such as fruits, vegetables, legumes, whole grains, and minimally processed proteins, may not only improve overall health but also contribute to lowering cancer risk.
Even small changes — like cooking more meals at home, swapping packaged snacks for fresh fruit, or choosing a homemade sandwich over a pre-packaged one — can make a difference over time.
The study reinforces the idea that lung cancer prevention is multi-faceted. Smoking cessation, air quality improvements, and healthy lifestyle choices all play a role. Diet, it seems, is part of that picture too.
While research continues, this evidence provides another reason to think carefully about what we eat and how lifestyle choices can influence health outcomes, including lung cancer. By looking beyond smoking and considering the full spectrum of prevention measures, individuals can take meaningful action to improve their chances of avoiding this serious illness.