WeeklySA_AdminFACTOR: New US research raises concerns that pesticide exposure in fruit, vegetables and whole grains may be contributing to rising lung cancer cases among non-smokers under 50 — especially women…
By Own Correspondent
LOS ANGELES — A diet rich in fruit, vegetables and whole grains has long been promoted as a cornerstone of good health.
But new research from the USC Norris Comprehensive Cancer Centre, part of Keck Medicine of USC, is raising questions about whether such diets may carry unintended risks for younger non-smokers. The study, presented at the annual meeting of the American Association for Cancer Research, suggests that non-smoking Americans under the age of 50 who consume higher-than-average amounts of these foods may face an increased risk of developing lung cancer.
Lead investigator Dr Jorge Nieva, a medical oncologist and lung cancer specialist, said the findings were unexpected and point to a possible environmental factor rather than the foods themselves.
“Our research shows that younger non-smokers who eat a higher quantity of healthy foods than the general population are more likely to develop lung cancer,” Nieva said. “These counter-intuitive findings raise important questions about an unknown environmental risk factor that needs to be addressed.” Researchers suspect that pesticide exposure may be a contributing factor. Commercially produced (non-organic) fruits, vegetables and whole grains are more likely to carry pesticide residues compared to many processed foods, meat and dairy products.
Nieva noted that agricultural workers — who are frequently exposed to pesticides — have historically shown higher rates of lung cancer, lending weight to the theory.
The study also found that young women who do not smoke are developing lung cancer at higher rates than men. Notably, women in the study also tended to have diets richer in fruits, vegetables and whole grains.
A Changing Profile
Lung cancer has traditionally been associated with older adults, smokers and men. The average age of diagnosis is around 71, and declining smoking rates since the 1980s have contributed to an overall drop in cases.
However, one group is defying this trend: non-smokers under 50 — particularly women — who are now seeing rising rates of lung cancer.
To better understand this shift, researchers launched the Epidemiology of Young Lung Cancer Project, analysing 187 patients diagnosed before the age of 50. Participants provided detailed information on diet, lifestyle and medical history.
Most had never smoked and were diagnosed with biologically distinct forms of lung cancer compared to those linked to smoking. Earlier genomic research has also shown that lung cancer in younger patients differs significantly from cases seen in older adults.
Researchers used the Healthy Eating Index (HEI) — a measure of diet quality — to compare participants’ eating habits with the broader US population.
The findings showed that young lung cancer patients had healthier diets overall, with an average HEI score of 65, compared to the national average of 57.
Participants also reported consuming higher daily servings of key food groups:
. 4.3 servings of dark green vegetables and legumes (vs 3.6 nationally)
. 3.9 servings of whole grains (vs 2.6 nationally)
While these foods are widely regarded as beneficial, the study suggests that higher exposure to pesticide residues through increased consumption could be a hidden risk factor.
Link Not Yet Proven
Researchers emphasise that the findings are preliminary and do not prove that healthy foods cause lung cancer. The study did not directly measure pesticide levels in participants. Instead, it estimated exposure based on existing data about typical residue levels in food categories.
The next phase of research will involve testing blood and urine samples to determine actual pesticide exposure and identify whether specific chemicals may be linked to increased cancer risk. “This work represents a critical step toward identifying modifiable environmental factors that may contribute to lung cancer in young adults,” Nieva said.
For now, health experts are not advising people to reduce their intake of fruits, vegetables or whole grains. Instead, the study highlights the need for closer scrutiny of food production systems — and the long-term health effects of pesticide exposure.
If anything, the real story here isn’t that healthy eating is dangerous — it’s that how food is grown may matter just as much as what we eat. – Science X
