Nutrition is a science, not an opinion

Science news from the FINUT Conference 2020

FINUT Conference 2020 – Online, 11th October: As the rates of obesity and diabetes continue to increase worldwide, public health strategies including the promotion of healthier dietary choices and reformulation of foods and drinks aim at achieving the recommended calorie, fat and sugar reduction in the diet. Low/no calorie sweeteners can play a role in this context as they provide sweet taste while allowing to replace sugar and to reduce calories in food products. Still, we are seeing conflicting scientific literature around the effects of low/no calorie sweeteners’ consumption on weight and glucose control. Which evidence should we trust? Aiming to address this question, the International Sweeteners Association (ISA) supported a scientific ‘meeting with the experts’ on 11th October as part of the FINUT 2020 virtual Conference on Food and Nutrition, organised online from 11th to 13th October by the Ibero-American Nutrition Foundation (Fundación Iberoamericana de Nutrición – FINUT) .

We need to base nutrition recommendations on the highest quality evidence”, both speakers agreed. But what do we mean by ‘highest quality evidence’? Both Dr Brian Cavagnari, from the Argentine Catholic University (Argentina) and Dr Hugo Laviada-Molina, from the Marist University of Mérida (Mexico), speaking at this scientific meeting, agreed that such evidence comes from randomised-controlled trials (RCTs) and from systematic reviews and meta-analyses of RCTs. In fact, these offer the best evidence for assessing any possible direct cause-and-effect relationship. And what RCTs show for low/no calorie sweeteners is that replacing sugars with them can help reduce calorie intake and, in turn, be a useful tool in weight management.1-3 RCTs further demonstrate that low/no calorie sweeteners do not affect glucose and insulin control, and when compared to sugar, they actually cause a lower blood glucose rise.4-6 Low/no calorie sweeteners therefore also constitute a helpful tool for people with diabetes.7

In contrast to RCTs, and as highlighted by Dr Brian Cavagnari in his presentation, some observational studies suggest a positive association between low/no calorie sweeteners’ consumption and obesity or diabetes. However, taking into account the limitations of each study design is crucial: for example, and contrary to RCTs, observational studies cannot prove any causal relationship as they cannot take into account all potential confounding factors nor exclude the possibility that reverse causality may affect the results.2 This means for example that someone who is overweight may turn to low/no calorie sweeteners in their effort to reduce overall calorie intake, and not the other way around. On this basis, observational studies rank lower in the hierarchy of evidence, while evidence from RCTs is rated as of higher quality.

In his presentation, Dr Hugo Laviada-Molina pointed to another important aspect to be considered when assessing research on low/no calorie sweeteners: the comparator used in each study.3 In fact, when low/no calorie sweeteners are compared to a non-caloric comparator like water or placebo, we should not expect they would have an effect on calorie intake, body weight or glucose control. Indeed, low/no calorie sweeteners are no magic bullet. Instead, they should be studied for what they are: food ingredients aimed at providing sweet taste while replacing sugar and reducing calories in foods and drinks. On this basis, and when low/no calorie sweeteners are studied in comparison to sugar, the highest quality evidence clearly shows a favourable effect of low/no calorie sweeteners on calorie reduction, and in turn on weight loss, and on glucose control.7 Of course, and as highlighted by Dr Laviada-Molina, their potential beneficial effects depend on the amount of sugar displaced. That is why the comparator in each study matters!

Speakers closed the session by reminding the audience that “nutrition is a science, not an opinion”. Both speakers further emphasised the need to consider the totality of published scientific work in each area, and to weigh the quality of the evidence in light of Evidence-Based Medicine (hierarchy of evidence) and the clinical significance of the study findings.

To read more about the ISA participation to the FINUT Conference 2020, please click here.

Engage in the conversation on social media about FINUT Conference 2020 by using #FINUT2020 and share your thoughts on the ISA-supported session by using #ISAatFINUT.

  1. Rogers PJ, Hogenkamp PS, de Graaf K, et al. Does low-energy sweetener consumption affect energy intake and body weight? A systematic review, including meta-analyses, of the evidence from human and animal studies. Int J Obes 2016; 40(3): 381-94
  2. Cavagnari BM. Edulcorantes no calóricos y peso corporal. (Non-caloric sweeteners and body weight). MEDICINA (Buenos Aires) 2019; 79: 115-122
  3. Laviada-Molina H, Molina-Segui F, Pérez-Gaxiola G, et al. Effects of nonnutritive sweeteners on body weight and BMI in diverse clinical contexts: Systematic review and meta-analysis. Obesity Reviews 2020; 21(7): e13020
  4. EFSA Scientific opinion on the substantiation of health claims related to intense sweeteners. EFSA 2011 Journal 9(6): 2229, and 9(4): 2076.
  5. 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
  6. Greyling A, Appleton KM, Raben A, Mela DJ. Acute glycemic and insulinemic effects of low-energy sweeteners: a systematic review and meta-analysis of randomized controlled trials. American Journal of Clinical Nutrition 2020; 112(4): 1002-1014
  7. Laviada-Molina H, Escobar-Duque ID, Pereyra E, et al. Consenso de la Asociación Latinoamericana de Diabetes sobre uso de edulcorantes no calóricos en personas con diabetes. Rev ALAD 2018; 8: 152-74