A study has found that drinking coffee does not change a person's risk of being diagnosed with – or dying – from cancer. QIMR Berghofer's research, published in the International Journal of Epidemiology, was the result of a large Mendelian randomisation study that looked at data from 300,000 people.
QIMR Berghofer senior author and head of Statistical Genetics Group, Associate Professor Stuart MacGregor, said: “We know that coffee is one of the most popular drinks in the world, and there continue to be mixed messages about the role it plays in disease. We also know that a preference for coffee is heritable.
“Our two-pronged research looked at whether cancer rates differed among people with different levels of self-reported coffee consumption, and whether the same trend was seen when we replaced self-reported consumption with genetic predisposition towards coffee consumption.
“We found there was no real relationship between how many cups of coffee a person had a day and if they developed any particular cancers.
“The study also ruled out a link between coffee intake and dying from the disease.”
MacGregor said coffee contains a complex mixture of bioactive ingredients, including substances such as caffeine and kahweol, which have been shown to display anti-tumour effects in animal studies.
But its potential anti-cancer effect on humans has not been established. Studies to date have produced conflicting findings for overall cancer risk and for individual cancers such as breast and prostate cancers.
QIMR Berghofer lead researcher, Jue-Sheng Ong, said the study also looked at some common individual cancers such as breast, ovarian, lung and prostate cancers and found drinking coffee did not increase or decrease their incidence.
“There was some inconclusive evidence about colorectal cancer, where those who reported drinking a lot of coffee had a slightly lower risk of developing cancer, but conversely examination of data from those people with a higher genetic predisposition to drink more coffee seemed to indicate a greater risk of developing the disease,” Ong said.
“The disparity in those findings would suggest more research is needed to clarify if there is any relationship between colorectal cancer and coffee.”
