No evidence that low calorie sweeteners may adversely affect glycaemic response and gut microbiota

Posted: 03 October 2018

ISA response to study findings presented at 54th EASD annual meeting by Young et al.

Following a presentation of preliminary results from an ongoing, not yet published, clinical trial by Young et al. at the 54th annual meeting of the European Association for the Study of Diabetes (EASD), the International Sweeteners Association (ISA) would like to draw attention to the collective evidence from clinical trials demonstrating that low calorie sweeteners have no impact on blood glucose control in humans1,2,3 and that they do not adversely affect glycaemic response4.

Low calorie sweeteners are consumed at such low levels that they are unlikely to have a direct, clinically meaningful impact on the gut microbiota. While there may be a need for well-designed human clinical trials in the future that would examine potential effects on gut microbiota in the context of human realistic consumption levels, the available wealth of robust scientific data show that low calorie sweeteners have no impact or adverse effect neither on blood glucose control nor on insulin sensitivity. It is also necessary to avoid extrapolating any effect of one low calorie sweetener on the gut microflora to all sweeteners, as well-documented data confirms there are differences in their chemistry, their movement through the body, and the amount of low calorie sweeteners or metabolites that reach the gut microflora5,6.

It is also important to mention that, while several studies exploring the effects of diet composition on the gut microbiome have been conducted, there is still no conclusive evidence on how certain foods or nutrients may influence the diversity, abundance and different profiles of the gut microbiota, and about how these changes may affect certain health outcomes, such as obesity, diabetes or metabolic syndrome7,8. Consequentially, any theories of adverse effects of low calorie sweeteners on the gut microbiota based on the presentation of preliminary findings of this study by Young et al. would be only speculative.

Actually, the gut microbiome profile can daily and promptly change, even within 24 hours, just with variations in daily food intake and diet composition8. A different diet composition between the intervention and the control group could largely influence the outcomes of this trial.

Low calorie sweeteners, when used instead of sugar and as part of a balanced diet and a healthy lifestyle, can be a helpful tool for people with diabetes for whom glycaemic control is fundamental.


  1. Nichol AD, Holle MJ, An R. Glycemic impact of non-nutritive sweeteners: a systematic review and meta-analysis of randomized controlled trials. Eur J Clin Nutr 2018; 72: 796-804
  2. Tucker RM, Tan SY. Do non-nutritive sweeteners influence acute glucose homeostasis in humans? A systematic review. Physiol Behav 2017; 182: 17-26
  3. Grotz, VL, Pi-Sunyer X, Porte DJ, Roberts A, Trout JR. A 12-week randomized clinical trial investigating the potential for sucralose to affect glucose homeostasis. Regul Toxicol Pharmacol 2017; 88: 22-33
  1. Lohner S, Toews I, Meerpohl JJ. Health outcomes of non-nutritive sweeteners: analysis of the research landscape. Nutr J 2017; 16(1): 55
  2. Magnuson BA, Carakostas MC, Moore NH, Poulos SP, Renwick AG. Biological fate of low-calorie sweeteners. Nutr Rev 2016; 74(11): 670-689
  3. Sylvetsky AC, Rother KI. Nonnutritive Sweeteners in Weight Management and Chronic Disease: A Review. Obesity 2018; 26: 635-640
  4. Castaner O, Goday A, Park Y-M, et al. The gut microbiome profile in obesity: A systematic review. Int J Endocrinol 2018; 2018: 4095789
  5. Willson K, Situ C. Systematic review on effects of diet on gut microbiota in relation to metabolic syndrome. J Clin Nutr Metab 2017; 1: 2