Adults who consumed a diet high in fiber and yogurt had a lower risk of developing lung cancer, according to recent research published in JAMA Oncology.

“For the first time to our knowledge, a potential synergistic association between fiber and yogurt intake on lung cancer risk was observed,” Xiao-Ou Shu, MD, PhD, of Vanderbilt University Medical Center in Nashville, and colleagues wrote in their study. “Although further investigation is needed to replicate these findings and disentangle the underlying mechanisms, our study suggests a potential novel health benefit of increasing dietary fiber and yogurt intakes in lung cancer prevention.”

High-fiber foods. Source: Getty

Shu and colleagues performed a pooled analysis of 1,445,850 adults from the United States, Europe, and Asia in 10 prospective cohorts between November 2017 and February 2019 where any participants with a history of cancer were excluded. The researchers analyzed the risk of lung cancer and histological type against participants’ diets, including fiber and yogurt consumption. In total, the dietary habits of 627,988 men (mean age, 57.9 years) and 817,862 women (54.8 years) were analyzed with up to median 8.6 years of follow-up.

The researchers identified 18,822 cases of incident lung cancer; 62.2% of participants reported yogurt consumption with a median intake of 23.3 (5.7-73.4) g/d, and a median dietary fiber intake of 18.4 g/d. After adjusting for smoking status and number of pack-years, there was an inverse association between risk of lung cancer and the highest intake of fiber compared with the lowest fiber intake (hazard ratio, 0.83; 95% confidence interval, 0.76-0.91). High consumption of yogurt was also associated with a lower risk of lung cancer compared with participants with the lowest yogurt consumption (HR, 0.81; 95% CI, 0.76-0.87). These associations were consistent across patients of different genders, race/ethnicities and lung cancer types, researchers said. Participants who had both the highest fiber intake and the highest yogurt consumption had a 33% reduced risk of lung cancer compared with participants who did not consume yogurt and had the lowest fiber intake (HR, 0.67; 95% CI, 0.61-0.73) and in participants who did not smoke (HR, 0.69; 95% CI, 0.54-0.89).

“[T]he inverse association of lung cancer risk with dietary fiber and yogurt consumption was more evident for squamous cell carcinoma and among participants with proinflammatory conditions (eg, heavy consumers of alcohol), suggesting that fiber and yogurt may exert beneficial effects on lung carcinogenesis via anti-inflammatory mechanisms,” Shu and colleagues said.