To correct for that, the researchers used genetic data to find people who were naturally predisposed to like and drink coffee and used that criteria as a replacement for simple self-reported consumption.
“The genetic data gives us a much more robust indicator of whether changing your coffee consumption would change your cancer risk,” Professor MacGregor said.
The two-pronged survey looked at 300,000 coffee drinkers in Britain for general cancer risks.
QIMR Berghofer lead researcher Jue-Sheng Ong said the study also looked at the risk of developing individual cancers from drinking coffee, similarly finding no benefit or detriment from a morning latte or long black.
“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,” Mr Ong said.
“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.”
Professor MacGregor said the results of the study might seem frustrating or irrelevant to the regular person who just wanted to know if they should put the kettle on, but it was important to get to the bottom of whether coffee was having an effect on people’s health.
“There are genes for whether you have a taste for tea or coffee, there are genes which govern how your body processes caffeine,” he said.
“So there are genes for cancer and genes for coffee consumption, and you need to triangulate whether there’s any association.”
Figures from the Australian Bureau of Statistics show 46 per cent of Australians drank coffee at least once in 2011-12.
However, there is currently no agreed-upon standard healthy intake advice for caffeine in Australia.
Globally, about 150 million bags of coffee are consumed every year, with Australians consuming about 2.6 kilograms per capita.
The research was funded by the National Health and Medical Research Council and has been published in the International Journal of Epidemiology.
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Stuart Layt covers health, science and technology for the Brisbane Times. He was formerly the Queensland political reporter for AAP.