A review of the latest scientific evidence
- Low calorie sweeteners do not affect blood glucose or insulin levels.
- Using low calorie sweeteners in place of sugar and as part of an overall healthy diet and lifestyle can be a helpful strategy for people with diabetes and obesity for whom glycaemic and weight control are fundamental.
- This information is especially important to healthcare professionals, who seek evidence-based facts about low calorie sweeteners’ use as a means to reduce sugar intake, including in the diet of people with diabetes.
Low calorie sweeteners have been proposed for decades as an alternative sweet-tasting option to sugar in the diet of people with diabetes because they don’t have any effect on blood glucose levels or on insulin secretion.1 This is not a surprise and is in line with the fact that low calorie sweeteners contribute no, or virtually no, calories nor carbohydrates to the diet. However, despite the large body of evidence supporting that low calorie sweeteners have no impact on glycaemic control, media reports are still casting doubts on their role in the diet of people with diabetes.
What is the position of scientific and regulatory organisations worldwide?
In its latest Medical Nutrition Therapy recommendations, the American Diabetes Association (ADA) supports that “The use of non-nutritive sweeteners has the potential to reduce overall calorie and carbohydrate intake if substituted for caloric sweeteners and without compensation by intake of additional calories from other food sources.”2
Furthermore, in 2011 the European Food Safety Authority (EFSA) approved a health claim supporting that “Consumption of foods sweetened with low calorie sweeteners instead of sugar induces a lower blood glucose rise after their consumption compared to sugar-containing foods”.3
So, how come their beneficial effect has been set in question in the past few years?
Human trials vs. isolated findings in animal and in vitro studies
Some studies published in the past decade led to the generation of theories supporting that low calorie sweeteners would adversely affect glucose metabolism via effects on insulin secretion and/ or incretin release (GLP-1 and GIP). The hypothesis stemmed largely from studies in isolated cells or tissues suggesting potential effects of low calorie sweeteners on gut sweet taste receptors, or more recently from animal studies supporting an impact on gut microbiome.4
However, these effects have not been demonstrated in humans, and contrary to these theories, a strong body of evidence from randomised clinical trials (RCTs), the strongest study design in human nutrition science, clearly shows that low calorie sweeteners do not affect post-prandial blood glucose or insulin levels, nor do they affect long-term glycaemic control. In fact, most clinical trials investigating the potential for low calorie sweeteners to affect blood glucose control by alteration of gut hormonal responses do not show clinically meaningful effects on circulating incretin levels.4,5,6
Recently published long-term trial helps address whether consumption of the low calorie sweetener sucralose would be likely to affect glucose control.
Investigating the effect of daily intake of sucralose at levels close to the ADI for 12 weeks in 47 healthy male volunteers, a RCT by Grotz et al.6 concluded that there were no statistically significant differences between sucralose and placebo groups in fasting or post-prandial glucose, long-term glucose control (HbA1c) or in insulin homeostasis.
These findings are also consistent with a 3-month study in people with type 2 diabetes that found no effect on HbA1c, a measure of long-term glycaemic control, as well as with numerous shorter-term RCTs showing no effect of sucralose on blood glucose control.6,7
This latest publication by Grotz et al. builds to the current evidence that long-term, repeated daily consumption of low calorie sweeteners would not adversely affect blood glucose control and is especially important to healthcare professionals, who seek evidence-based facts in relation to the use of low calorie sweeteners as a means to reduce sugar intake, including in the diet of people with diabetes.
In times when obesity and diabetes are on the rise globally, low calorie sweeteners can offer a sweet-tasting alternative with few or no calories, helping people with diabetes or individuals who are concerned about managing their body weight to reduce their sugar and caloric intake. Especially for people with diabetes, low calorie sweeteners offer broader food choices by providing the pleasure of sweet taste without raising blood glucose.