Diets high in polyunsaturated, vegetable fats reduce liver cancer risk

Diets consisting of higher vegetable fat and polyunsaturated fat intake correlated with a lower risk for hepatocellular carcinoma, including cases in which individuals replaced other animal, dairy, or saturated fats with vegetable and polyunsaturated fats, according to data.

While HCC rates continue to increase in the U.S., approximately 35% of cases cannot be explained by currently known risk factors, such as hepatitis B and hepatitis C, alcohol intake, smoking, and metabolic disorders, according to Wanshui Yang, PhD, from Brigham and Women’s Hospital and Harvard Medical School in Boston, Massachusetts, and colleagues.

“Identifying other modifiable factors such as diet to prevent development of HCC is crucial to decrease the morbidity and mortality of HCC,” they wrote. “We investigated the associations of total and specific dietary fats, and fats from different food sources with risk of developing HCC.”

Using data from two previously published studies comprised of 138,483 men and women, the researchers found that intake levels of energy percentage from animal fats decreased in both men and women between 1986 and 2010, while the consumption of energy percentage from vegetable fats increased during the same period.

Yang and colleagues identified 160 incident cases of HCC during an average follow-up of 26.6 years. Multivariate analysis showed that intake of vegetables fats (HR = 0.61; 95% CI, 0.39-0.96) correlated with a lower HCC risk compared with no such association for animal and dairy fats. Additionally, replacing animal or dairy fats with the equivalent amount of vegetable fats lowered HCC risk (HR = 0.79; 95% CI, 0.65-0.97).

Intake of monounsaturated fats (HR = 0.76; 95% CI, 0.47-1.25) and polyunsaturated fats (HR = 0.71; 95% CI, 0.46-1.08), including both n-3 and n-6 polyunsaturated fatty acids, showed similar HCC risk reduction.

Although there was no association between saturated fat intake and HCC risk, replacing saturated fats with an equivalent amount of monounsaturated or polyunsaturated fats correlated with a lowered risk (HR = 0.77; 95% CI, 0.64-0.92).

Yang and colleagues noted that similar studies have shown inconsistent findings regarding the correlation between dietary fats and HCC risk, and suggested that this may be in part due to different intake levels and food sources of fats among different study populations.

“Given the limited number of HCC cases and inconsistent results in previous studies, more studies are warranted to confirm our findings, ideally with pooled analysis across cohorts in different populations,” they concluded. “These findings, if validated, have important public health and clinical relevance.” – by Talitha Bennett

Disclosures: Yang reports receiving grants and personal fees from Bayer Pharma AG and personal fees from Pfizer and Janssen. The remaining authors report no relevant financial disclosures.