Study Finds Surprising Link Between Healthy Diet and Lung Cancer in Young Non-Smokers

Eating a diet high in fruits and vegetables was found to have an unexpected association with lung cancer among younger non-smokers, according to preliminary research from the USC Norris Comprehensive Cancer Center at Keck Medicine.

The observational study, led by Dr. Jorge Nieva, analyzed dietary habits, smoking history and demographic data from 187 patients diagnosed with lung cancer at age 50 or younger. The findings were presented this month at the American Association for Cancer Research annual meeting in San Diego, though they have not yet undergone peer review.

Researchers discovered that among non-smokers, there appeared to be a connection between healthier-than-average diets – those rich in fruits, vegetables and whole grains – and lung cancer development. The data showed young lung cancer patients consumed more servings of dark green vegetables, legumes and whole grains compared to the average U.S. adult.

“There is a large subset of lung cancer patients whose disease is not caused by smoking,” Dr. Nieva told Fox News Digital. He noted that lung cancer is becoming increasingly common among non-smokers under 50, particularly women, despite decades of declining smoking rates nationwide.

The research team hypothesized that pesticides used on conventionally grown produce might be a contributing factor. “Commercially produced non-organic fruits, vegetables and whole grains are more likely to be associated with a higher residue of pesticides than dairy, meat and many processed foods,” Dr. Nieva explained. He also pointed out that agricultural workers with occupational exposure to pesticides tend to have higher rates of lung cancer.

This potential connection to pesticides represents a concerning paradox – foods typically considered part of a healthy diet may contain chemicals that could increase cancer risk in some individuals.

The study does have several limitations, as Dr. Nieva acknowledged. It relied on survey data and participants’ memories of their food consumption patterns. Additionally, the self-selected nature of survey participants could have introduced bias into the findings. Rather than testing specific foods for pesticide content, the researchers based their analysis on average pesticide levels reported for certain food types.

Dr. Marc Siegel, Fox News senior medical analyst who was not involved in the research, described the study as “interesting” but cautioned that it “raises far more questions than it answers.”

“It is a small study and observational, so no proof,” Dr. Siegel said. “It is possible that the increased lung cancer risk could be due to pesticide exposure in whole farmed foods, but it is by no means certain. How much exposure is needed? How much of it gets into food and in which areas? This requires much further study.”

Moving forward, the USC research team plans to test patients’ blood and urine samples to directly measure pesticide levels. While the current findings show only an association and do not establish causation, Dr. Nieva recommends that consumers wash produce thoroughly before eating and choose organic foods when possible.

Kayla Nichols, communications director for Pesticide Action & Agroecology Network, expressed agreement with the study’s conclusion that more research is needed on the rise in lung cancer among people consuming diets higher in produce and fiber.

“There is a bounty of existing research that already links pesticide exposure to increased risk of multiple types of cancers,” Nichols stated. She called for additional research on chronic, low-level exposures to pesticides and more effective policies to protect consumers from pesticide residues on food.

The study received funding support from the National Institutes of Health and the National Cancer Institute, as well as from industry partners including AstraZeneca and Genentech.

“This work represents a critical step toward identifying modifiable environmental factors that may contribute to lung cancer in young adults,” said Dr. Nieva. “Our hope is that these insights can guide both public health recommendations and future investigation into lung cancer prevention.”