April 22, 2021
Liver cancer is the seventh leading cause of cancer deaths in Australia and unfortunately, it’s on the rise. We know that factors such as excessive alcohol consumption, tobacco smoking, fatty liver disease and liver damage from hepatitis B and C infections can increase the risk of liver cancer. We also know that generally, a healthy diet may play a preventative role against some cancers, while a poor diet can increase the risk of other cancers. In terms of liver cancer in particular, we wanted to know: is diet important? A systematic review led by Dr George and a team of dietetics students from Deakin University has helped answer this question.
We found that dietary patterns, including the Mediterranean diet, may protect against liver cancer. The Mediterranean diet is a plant-based diet rich in whole foods such as vegetables, fruits, wholegrains, legumes, extra-virgin olive oil, fish and fermented dairy, including yoghurt and cheese.
Eating according to the Chinese and US dietary guidelines, measured with the ‘Chinese Healthy Eating Index’ and the ‘Healthy Eating Index-2015’ respectively, was also associated with a lower risk of liver cancer. Both dietary patterns encourage the consumption of a variety of foods including vegetables, fruits, wholegrains, dairy and lean protein such as fish, poultry, eggs and meat. They also encourage avoiding salt, oil, sugar and alcohol. A summary of dietary patterns, foods and nutrients and their associated risk of liver cancer can be seen in the image below.
We all know that vegetables are important for our health. So, it may not come as a surprise that a diet rich in vegetables was also found to reduce liver cancer risk. What was surprising, however, is that fruit consumption did not show any effect on liver cancer risk. In line with dietary recommendations, our review agreed that we should stay away from processed (salami, sausages) and red meat, which may increase risk of liver cancer. However, white meat, such as chicken and fish, and meat alternatives like tofu, were associated with a decreased risk of liver cancer.
The jury is still out for dairy, as studies showed mixed results regarding the impact dairy foods have on liver cancer risk. However, it seems that steering away from high fat options like butter may be a good idea, whereas yogurt may be protective. Coffee consumption was associated with a reduced risk of liver cancer, with those who drank coffee daily found to have a 51% lower risk compared with those who did not drink coffee at all. When it comes to soft drinks (sugar-sweetened beverages (SSB)), the evidence is clear. People who drank more than 6 serves of SSB per week (less than one per day), had a significantly higher risk of liver cancer compared to those who did not drink any SSBs.
The bottom line?
Eating well is important when it comes to health overall, and eating to prevent liver cancer is no exception. Following dietary patterns such as the Mediterranean Diet and national dietary guidelines like the US and Chinese dietary guidelines seem to be protective. These dietary patterns all recommend eating a diet rich in whole foods, especially vegetables, wholegrains, legumes, fish, poultry. And good news, that coffee can also stay put!
Anna Broughton is an Accredited Practising Dietitian and recent graduate form Deakin University. Anna is currently employed as an NDIS dietitian in Geelong, working with children and adults with disability to help increase their independence and support them in achieving their goals. Anna has a special interest in many areas of nutrition and dietetics including population and community nutrition, oncology, clinical dietetics, disability support and paediatrics.
Dr Elena George is an Accredited Practising Dietitian, Lecturer in Nutrition and Dietetics and early career researcher at Deakin University. Elena is interested in translational research, in particular enhancing evidence-based practice in dietetics through research. Her interests are in development and delivery of dietary interventions (Mediterranean diet) for the prevention and management of chronic diseases (type 2 diabetes, non-alcoholic fatty liver disease, metabolic syndrome and cardiovascular disease). Elena has experience as a clinician running her own successful private practice and as a research dietitian in tertiary hospitals.