Increased intake of whole grains correlated with a reduced risk for hepatocellular carcinoma among adults regardless of cancer etiology, according to study results published in JAMA Oncology.
“Consumption of whole grains and dietary fiber, especially cereal fiber, has been associated with lower risk of obesity, type 2 diabetes, and nonalcoholic fatty liver disease, which are known predisposing factors for HCC,” Wanshui Yang, PhD, from Anhui Medical University in China, and colleagues wrote. “In addition to improving insulin sensitivity and metabolic regulation and decreasing systemic inflammation, intake of whole grains and dietary fiber may improve gut integrity and alter gut microbiota composition, thereby leading to increased production of microbiota-related metabolites, including short-chain fatty acids, particularly butyrate. Gut integrity, the composition of gut microbiota, and metabolites may play an important role in the development of liver diseases, including HCC.”
Yang and colleagues retrospectively assessed patient data and frequency food questionnaire responses from the Nurses’ Health Study and the Health Professionals Follow-up Study. Of 125,455 participants assessed during a follow-up of 24.2 years, the researchers identified 70 women and 71 men with incident HCC.
Multivariate analysis comparing the highest to lowest tertiles showed that higher whole grain intake correlated significantly with a lower risk for HCC (HR = 0.63; 95% CI, 0.41-0.96). Assessment of specific whole grain and grain subcomponents showed similar correlations as the pooled analysis.
The researchers also found a suggestive trend between lower risk for HCC and intake of bran, total germ, and cereal fiber. Conversely, they observed no significant correlation between total fiber intake, fruit, or vegetable fiber intake and the risk for HCC.
In an analysis of HCC etiology, there was no evidence of any associations between whole grain, bran and germ, or dietary fiber intake with the risk for HCC that developed from hepatitis B, hepatitis C, or cirrhosis. Additionally, age, BMI, physical activity, smoking, alcohol intake, diabetes type 2, and aspirin use had no significant interaction with the link between whole grain intake and HCC risk.
“These findings should be interpreted with caution, given the lack of data on HBV/HCV infection in the full cohort and the limited number of participants with HCC in the analysis,” Yang and colleagues wrote. “Future studies that carefully consider HBV and HCV infections are needed to further examine these associations in other racial/ethnic or high risk populations and to elucidate the underlying mechanisms. If our findings are confirmed, increasing whole grain consumption may serve as a possible strategy for prevention of primary HCC.” – by Talitha Bennett
Disclosure: Yang reports no relevant financial disclosures. Please see the full study for all other authors’ relevant financial disclosures.