Don’t believe what you read about the benefits of artificial sweeteners.
That’s the message from University of Sydney researchers whose recent analysis shows widespread bias – and therefore inaccuracy – in industry-funded research into fake sugars.
The review, published in the latest edition of PLOS ONE journal, analysed 31 studies into artificial sweeteners between 1978 and 2014. The studies considered both the potentially beneficial effects of artificial sweeteners, such as weight loss, as well as harmful effects like diabetes.
The paper looked at two potential sources of bias 1) who funded the study and 2) who authored the study (and whether they had conflicts of interest due to ties to the sweetener industry. The sweeteners under review were acesulfame potassium (E950), aspartame (E951), salt of aspartame-acesulfame (E962), neotame (E961), saccharin (E954) and sucralose (E955).
This is the first major review of the effects of funding bias in nutrition research from the Charles Perkins Centre’s Bias in Research project node, a new research collaboration aimed at improving health policy by encouraging unbiased and evidence-based research.
The researchers began by assessing the relationship between review funding and review results. They found that artificial sweetener industry sponsored reviews were more likely to have favourable results (75% of cases) than non-industry sponsored reviews, including reviews with no funding disclosed (less than 5 % of cases).
In terms of the relationship between review sponsorship and review conclusions (that is to say, the summing up at the end of the research paper which is what tends to be reported on), artificial sweetener industry sponsored reviews were more likely to have favourable conclusions (100% of the time) than non-industry sponsored reviews, including reviews with no funding disclosed, (around 65% of the time).
“It’s alarming to see how much power the artificial sweetener industry has over the results of its funded research, with not only the data but also the conclusions of these studies emphasising artificial sweeteners’ positive effects while neglecting mention of any drawbacks,” said co-author Professor Lisa Bero , head of the Charles Perkins Centre’s bias node.
“The results of these studies are even more important than the conclusion, as the actual results are used in the development of dietary guidelines.”