World Diabetes Day, celebrated on 14 November, provides an opportunity to highlight the importance of nutrition in early action for diabetes prevention and management. For people living with diabetes, making informed dietary choices, managing carbohydrate intake and reducing excessive free sugar consumption can all contribute to an overall healthy eating pattern that is crucial for supporting healthy blood glucose levels.
Reducing sugar intake, however, does not necessarily mean giving up sweet-tasting foods and beverages. Low/no calorie sweeteners (LNCS) offer one approach to reducing sugar consumption while maintaining sweetness. However, the evidence on their role in diabetes management is sometimes conflicting and needs to be interpreted in the context of different study designs and findings.1 Systematic reviews and meta-analyses of randomised controlled trials (RCTs) generally indicate neutral effects of LNCS on measures of glycaemia, which can be beneficial when LNCS replace sugars that would otherwise cause a spike in blood glucose levels after food consumption.2 In contrast, meta-analyses of observational studies have reported mixed findings, with results varying according to study methodology and the use of bias-adjusted analyses.1-4
Further human research can help clarify the effects of LNCS on blood glucose regulation and other aspects of metabolic health. Three new studies published in 2026 provide new insights into these questions, examining the effects of sweetener-containing beverages and individual LNCS on glycaemic control, insulin sensitivity, and hormonal responses.
What do these findings mean for people living with diabetes, and how can they inform the role of LNCS in a balanced dietary approach?
Replacing sugar without compromising glycaemic control
For people living with diabetes, reducing sugar intake while maintaining a balanced and enjoyable diet can be an important consideration. Replacing sugar-sweetened beverages with drinks sweetened with LNCS is a common practice in diabetes to avoid blood glucose spikes. However, questions remain about the potential benefits of this substitution, while the most common recommendation is to replace all sweetened beverages with water for better glycaemic control. To address this issue, the SODAS randomised controlled trial, published in Diabetes Care in 2026, investigated whether replacing LNCS-sweetened beverages with water improved glycaemic control in 181 adults with type 2 diabetes.5 Participants were assigned either to continue consuming an LNCS-sweetened beverage of their choice or to replace it with water for 24 weeks.
Contrary to the expectation that replacing LNCS beverages with water would improve glycaemic outcomes, HbA1c increased by 0.29 percentage points more in the water group than in the LNCS beverage group. No statistically significant differences were observed in the secondary outcomes, including fasting glucose, body weight and continuous glucose monitoring measures. The findings provide useful evidence for people with diabetes who want to keep enjoying sweet-tasting beverages but wish to reduce sugar intake.
Do sweeteners affect insulin sensitivity and hormonal responses?
Insulin sensitivity is another important consideration in metabolic health. A small pilot study published in the Journal of the Endocrine Society examined the effects of saccharin consumption in 14 adults with overweight.6 Participants consumed saccharin at 5 mg/kg body weight per day for three months. Using the hyperinsulinaemic-euglycaemic clamp, a well-established method for directly assessing insulin sensitivity, researchers found no significant change in insulin sensitivity or body weight. However, the small sample size and the lack of a control group limit the conclusions that can be drawn.
Another randomised controlled trial published in The Journal of Nutrition investigated the acute effects of stevia in three groups: normal-weight individuals, individuals with overweight, and people with type 2 diabetes.7 Using a crossover design, participants received stevia, water, glucose or stevia combined with glucose. Stevia alone did not significantly alter responses compared with water, while adding stevia to glucose did not significantly change responses compared with glucose alone. The researchers found no material differences in blood glucose, insulin or several gut and pancreatic hormones involved in glucose regulation and appetite, including GLP-1, GIP and glucagon. These findings suggest that acute stevia consumption did not materially alter the measured glycaemic, hormonal or appetite responses, including in participants with type 2 diabetes.
Putting the findings into perspective
Together, these studies add to the evolving evidence on LNCS and metabolic health. They found that the sweeteners examined do not affect the measured glycaemic or insulin-sensitivity outcomes, although the studies differ substantially in design, duration and population.
For diabetes management, the broader dietary context remains essential. For people who prefer sweet-tasting products, LNCS may offer an additional option when replacing sugar-containing alternatives, potentially helping to reduce sugar intake without necessarily sacrificing sweetness. Diabetes-related organisations such as the American Diabetes Association (ADA), the Diabetes and Nutrition Study Group of the European Association for the Study of Diabetes (EASD), and Diabetes UK recognise a potential role for LNCS in diabetes control.
The key message for World Diabetes Day is that effective diabetes management depends on an overall healthy dietary pattern, individual needs and informed choices. LNCS can be considered as one potential tool for sugar reduction, rather than a standalone solution for diabetes. Continued high-quality research will help clarify their role in different dietary contexts.