A new study presented at this year’s annual meeting of the European Association for the Study of Diabetes (EASD) in Lisbon, Portugal (Sept. 11-15) suggested that artificial sweeteners can change the body’s response to glucose when consumed in large amounts, potentially leading to the risk of developing type 2 diabetes (T2DM). Meanwhile organizations such as the International Sweeteners Association (ISA) questioned the study’s finding compared to the body of research indicating the contrary.
 
The study’s authors stated that past research has found that habitual consumption of large amounts of non-caloric artificial sweeteners (NAS) is associated with an increased risk of developing T2DM; however, the underlying mechanisms for how this occurs were unknown.
 
This study was conducted by Associate Professor Richard Young of the Adelaide Medical School, University of Adelaide, Adelaide, Australia, as well as colleagues from other Adelaide-based research institutions, and aimed to investigate the effects of consuming large amounts of NAS on the body’s response to glucose.
 
The researchers recruited 27 healthy subjects who were given a quantity of two different NAS (sucralose and acesulfame-K) equivalent to drinking 1.5L of diet beverage per day, or an inactive placebo. These were consumed in the form of capsules taken three times a day before meals over the two-week period of the study. At the end of the two weeks, subjects had their response to glucose tested, examining glucose absorption, plasma glucose, and levels of insulin and gut peptides.
 
The team found that NAS supplementation caused an increase in measures of the body’s response to glucose, measured using a technique known as the incremental area under the curve (iAUC). This was greater for both glucose absorption and blood glucose, while the iAUC for the gut peptide GLP-1, which acts to limit the rise in blood glucose after meals, was reduced. None of these measures were altered in those subjects who were given a placebo.
 
The study determined that just 2 weeks of NAS supplementation was enough to enhance glucose absorption and increase the magnitude of the response of blood glucose as a result. 
The authors concluded that, “This study supports the concept that artificial sweeteners could reduce the body’s control of blood sugar levels and highlights the potential for exaggerated post-meal glucose levels in high habitual NAS users, which could predispose them to developing type 2 diabetes.”
 
International Sweeteners Association Response
In response to study, the International Sweeteners Association (ISA) pointed to “the overwhelming body of evidence, including from studies by the same Australian research team, showing that low calorie sweeteners do not affect glucose control.” 
 
ISA said the initial press release discussing this research neglected to report the outcomes of a considerable number of studies published by the same authors, which consistently found no impact of low calorie sweeteners on blood glucose regulation. Additionally, ISA said the collective evidence from well-designed human studies supported that low calorie sweeteners do not adversely affect glycemic control in healthy individuals and in people with diabetes, e.g., by affecting total insulin secretion, glucose uptake and/or glucose utilization either by direct effect or via effects on incretins (gut hormones).
 
In fact, ISA noted the beneficial effect of low calorie sweeteners in post-prandial glucose is recognized also in a health claim authorized in Europe, further to the scientific opinion by EFSA: “Consumption of foods with low calorie sweeteners instead of sugar induces a lower blood glucose rise after their consumption compared to sugar-containing foods.”
 
ISA stressed that low calorie sweeteners cannot increase diabetes risk, but rather indicated they may offer a helpful strategy for people with diabetes for whom glycemic control is fundamental. This, they said, is in line with the fact that low calorie sweeteners contribute no carbohydrates to the diet. In the 2017 guidelines ‘Standards of Medical Care in Diabetes’, the American Diabetes Association supported that “non-nutritive sweeteners have the potential to reduce overall calorie and carbohydrate intake.”