Sweeteners and Health: a closer look at the totality of evidence
Systematic reviews (SR) of non-sugar sweeteners (NSS) present a puzzling picture. Depending on the questions asked, the keywords searched, and the selection criteria for studies included, SRs examine very different sub-sets of the published literature and, not surprisingly, reach different conclusions.
NSS have been extensively investigated for years, the subject of numerous SRs, even a "review of reviews"  . Toews et al.[ 2] covered a unique and particularly small sub-set of existing publications. On this basis, they concluded that NSS provide no health benefits, in spite of the positive results they report in terms of energy intake and BMI in children and adults.
As VS Malik remarked in her accompanying editorial  , many high-quality prospective cohort studies and RCTs  were left out. Other influential SRs  that reported benefits of NSS in terms of body weight management, appetite, and reduction in both sugar and energy intakes were not mentioned or discussed.
The conclusions of Toews et al. also conflict with consensus statements by several international scientific groups recommending the use of NSS 
Happily, Toews et al do agree with their peers on one point: no adverse effects could be identified in users of NSS. This is of crucial importance and supports the decisions by food safety agencies that have authorized NSS to be used in many parts of the world.
Nowhere is NSS use presented as the solution to obesity, even in works that report weight benefits. To reverse established obesity, a larger set of strategies have to be used.
But the totality of available evidence suggests that NSS can contribute to a beneficial change in energy balance directly (by decreasing the energy density of a number of products) and indirectly (by facilitating diet compliance over the long term).
Recommendations by WHO and others should reflect these positive findings.
 Mosdøl A, Vist GE, Svendsen C, et al. Hypotheses and evidence related to intense sweeteners and effects on appetite and body weight changes: A scoping review of review. Plos One 2018, 13:e0199558
 Toews I, Lohner S, Kullenberg de Gaudry D, et al. Association between intake of non-sugar sweeteners and health outcomes: systematic review and meta-analyses of randomised and non-randomised controlled trials and observational studies. BMJ 2018;363:k4718
 Malik V. Non‐sugar sweeteners and health. Editorial. BMJ 2018;363:k5005. doi:10.1136:bmj.k5005
 Piernas C, Beck J, Wang X, et al. Does diet-beverage intake affect dietary consumption patterns? Results from the Choose Healthy Options Consciously Everyday (CHOICE) randomized clinical trial. Am J Clin Nutr 2013;97:604-11.
 Peters J, Beck J, Cardel M. The effects of water and non-nutritive sweetened beverages on weight loss and weight maintenance: a randomised clinical trial. Obesity 2016;24:297-304.
 Rogers P, Hogenkamp P, de Graaf C, 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;40:381‐94.
 De La Hunty A, Gibson S, Ashwell M. A review of the effectiveness of aspartame in helping with weight control. Nut Bull 2006;32:116-28.
 Gibson S, Drewnowski A, Hill J, et al. Consensus statement on benefits of low-calories sweeteners. Nutr Bull 2014;39:386-9
 Serra-Majem L, Raposo A, Aranceta-Batrina J, et al. Ibero-American consensus on low- and no-calorie sweeteners; safety, nutritional aspects and benefits in food and beverages. Nutrients 2018 Jun 25;10(7). pii:E818.
Competing interests: Member of scientific advisory committees (CreaBio, European Fruit Juice Association, General Mills, International Sweeteners Association). Received travel and speaking honoraria from the International Life Science Institute (ILSI), the International Sweeteners Association, Mars, Mondelez, and Tate & Lyle.