Eating yogurt and fiber may lower the risk for lung cancer.
Fiber is the main source of prebiotics, the nondigestible foods that promote the growth of probiotics, and yogurt is a probiotic food. Scientists suspect that a healthy microbiome may explain the link.
The study, in JAMA Oncology, pooled data from 10 studies of diet and lung cancer incidence involving more than 1.4 million adults. Over an average follow-up of eight years, they found 18,882 cases of lung cancer.
Compared with people in the lowest one-fifth for fiber intake, those in the highest had a 17 percent lower risk of lung cancer. People who ate the most yogurt — an average three to four ounces a day — were 19 percent less likely to develop lung cancer that those who ate none.
People with both the highest fiber and highest yogurt intake had a 33 percent reduced risk compared with those who consumed the least. Although smokers remained at the highest risk for lung cancer, fiber and yogurt reduced their risk as well.
The reason for the association is not clear, said the senior author, Dr. Xiao-Ou Shu of Vanderbilt University, but “inflammation plays a major role in lung cancer, and we know that the gut microbiome plays a major role in reducing inflammation. People who eat a lot of fiber and yogurt have a healthier microbiome.”