Fiber and yogurt associated with lower risk of lung cancer
People who eat more fiber and yogurt may be less likely to develop lung cancer, a new research review states.
Our study suggests a potential novel health benefit of increasing dietary fiber and yogurt intakes in lung cancer prevention,” senior study author Dr. Xiao-Ou Shu of Vanderbilt University Medical Center in Nashville, Tennessee, and colleagues write.
Compared to people who never ate yogurt, those who consumed the most yogurt were 19% less likely to develop lung cancer, the analysis found.
10 previous studies reviewed
Researchers examined pooled data from 10 previous studies that included a total of almost 1.45 million adults in Asia, Europe, and the United States. After following people for an average of 8.6 years, 18,822 cases of lung cancer were documented.
Individuals with the highest fiber intake and highest yogurt consumption were 33% less likely than those with the lowest consumption of both to develop lung cancer, the study team reports in JAMA Oncology.
Changes in the gut microbiota
While the study wasn’t a controlled experiment designed to prove yogurt or fiber protects against lung cancer, it’s possible these kinds of foods might lead to changes in the gut microbiota - the bacteria living in our digestive tract - that help protect against cancer, the study authors hypothesize.
It’s also possible fiber and yogurt might help protect against inflammation, which in turn helps reduce the potential for tumors to develop, the researchers note.
Lots of prebiotics
Fiber-rich foods typically have lots of prebiotics, nondigestable compounds that can be fermented in the gut and serve as food for beneficial bacteria, the authors note. Yogurt has lots of those beneficial bacteria, or probiotics.
Considerable research links the gut microbiota to the immune system overall. And some recent studies have suggested that the gut microbiota may play a role in lung inflammation, the study authors point out.
The reduced risk of lung cancer associated with fiber and yogurt in the study persisted even after researchers accounted for smoking habits.
For people who never smoked, the lung cancer risk reduction associated with the highest levels of yogurt and fiber consumption was 31%, while for smokers it was 24% and for former smokers, 34%.