An increased supply of whole grains and fiber is associated with a reduced risk of hepatocellular carcinoma, the most common form of liver cancer, according to a large observational study with a long follow-up, published in Jama Oncology and coordinated by Xuehong Zhang of Brigham and Women’s Hospital, affiliated with Harvard Medical School in Boston.
Experts have long suspected that diet may be an important risk factor for hepatocellular carcinoma, but until now scientific evidence had only been produced regarding the consumption of certain mushroom-contaminated foods and large amounts of alcohol. In this case, the researchers focused instead on whole grains and dietary fiber, which had already been associated a lower risk of obesity, type 2 diabetes, and nonalcoholic liver steatosis-all known predisposing factors for hepatocellular carcinoma.
The team conducted a cohort study of 125,455 people and examined their intakes of whole grains, their components (bran and germ), and dietary fiber, which are present not only in unrefined grains but also in fruits and vegetables. Study participants were asked to fill out questionnaires regarding their eating habits every two years, and to analyze the data, the researchers then divided the study subjects into tertiles based on their consumption levels of the foods considered.
During an average follow-up that lasted a full 24 years, 141 participants were affected by hepatocellular carcinoma.
Statistical analysis of the data showed that a higher intake of whole grains was significantly associated with a lower risk of this cancer.
“If our results are confirmed, increasing fiber consumption of whole grains could serve as a possible strategy for primary prevention of hepatocellular carcinoma,” Zhang said in an email to Medscape Medical News.
E Nicola McKeown, an expert in nutrition epidemiology from Tufts University in Boston, commented that the benefits of these foods go beyond preventing a specific cancer: “More studies will be needed to ascertain the impact on liver cancer of whole grains, but introducing more of them into one’s diet is a good strategy for improving overall health.”.