GM pig study is hogwash, FSANZ says

A recent study that claims to cast doubt over the safety of genetically modified (GM) food is hogwash, Food Standards Australia New Zealand (FSANZ) says.

FSANZ published a response to Dr Judy Carman’s study, which studied pigs fed either a mixture of GM corn and GM soy or an equivalent non-GM diet for 23 weeks. Carman’s research team claims the pigs fed the GM diet had a higher incidence of severe stomach inflammation and enlarged uteri than the pigs fed the non-GM diet.

“There were no differences between pigs fed the GM and non-GM diets for feed intake, weight gain, mortality and blood biochemistry parameters but the authors attributed severe stomach inflammation and enlarged uteri to the GM diet,” the FSANZ response said.

FSANZ says the authors’ presentation of the stomach inflammation findings is flawed. “The authors have not provided convincing evidence that stomach inflammation was present,” the response said. According to FSANZ, stomach inflammation was determined only visually, rather than microscopically. In addition, FSANZ says, greater numbers of non-GM fed pigs exhibited inflammation of the stomach.

“The authors erred in their statistical approach to analysing the stomach ‘inflammation’ data,” FSANZ’s response said. “If the data are analysed using more appropriate statistical methods, no statistical association with diet exists.”

Pigs’ uterine weight can vary depending on their age and the stage of their reproductive cycle, FSANZ said, so it is not possible to attribute the increased uterine weight to the GM diet.

“Overall, the data presented in the paper are not convincing of adverse effects due to the GM diet and provide no grounds for revising FSANZ’s conclusions about the safety of previously approved glyphosate-tolerant and insect-protected GM corn lines and glyphosate-tolerant GM soy lines,” FSANZ’s response read.