Attack on controversial sugar study intensifies
The authors of a controversial study claiming that Australians are reducing their sugar consumption have admitted to an error in the presentation of data as the research comes under sustained attack.
In their The Australian Paradox study, Professor Jennie Brand-Miller and her colleague Dr Alan Barclay reported that although rates of obesity had trebled, per capita consumption of nutritive sweeteners had, paradoxically, dropped 16 per cent.
But on ABC Radio’s Background Briefing program, Professor Brand-Miller and Dr Barclay appeared to contradict one of the assertions made in their study, that per capita sales of sugar-sweetened beverages had decreased by 10 per cent.
On the program, Professor Brand-Miller said “it might be that a key word came out. It’s possible that this should be, ‘While nutritively sweetened beverages…10 per cent sweetened beverages decreased by 10 per cent.’ So I’ll double-check it.” In an email sent to the program, Dr Barclay said “the 10 per cent decline could not possibly refer to per capita sales of nutritively sweetened soft drinks”.
The basis for the study’s findings has been called into question by a peer-reviewed paper published in the journal BMC Public Health, “Trends in sugar supply and consumption in Australia: is there an Australian Paradox?”
In their conclusion, the authors observed that “the Australian Paradox assertion is based on incomplete data, as it excludes sugar contained in imported processed foods, which have increased markedly”.
“Available import data showed large increases in the volume and value of imported sweetened products between 1988 and 2010 to over 30 grams of sugar per person per day,” the authors said. “Value estimates of local production of sweetened products also show substantial increases in this period.”
Prominent economist Rory Robertson, who has been a long-standing critic of the Australian Paradox study, said its interpretation of data was flawed: “Four of the authors’ five separate indicators of consumption trend up, not down, in their own published charts, while their preferred measure is based on a data series that was discontinued as unreliable by the ABS after 1998-99”.
Mr Robertson said this was just one of many errors in the paper, and has called for its retraction.
Sydney University has appointed an external investigator to review the research.