A presentation by Dr John Sievenpiper at the ISA Conference 2018
Sugars have emerged as the dominant public health concern. Major health agencies have recommended that added/free sugars be reduced to <5-10% of calories. The use of low calorie sweeteners represent an important strategy to achieve these reductions. Although approved as safe by international regulatory agencies, there is an emerging concern that low calorie sweeteners may not have the intended benefit and may even increase the risk of obesity and its downstream cardiomeatbolic complications. Several health authorities have specifically recommended against the use of low calorie sweeteners to replace sugars. A careful review of the available evidence suggests that that a number of important methodological considerations have been overlooked such as reverse causality in prospective cohort studies and the nature of the comparator in randomized controlled trials. If one accounts for these considerations, then the concerns appear unfounded. Whereas prospective cohort studies that model low calorie sweeteners as baseline or prevalent exposures have shown an adverse association of low calorie sweeteners with weight gain and incident diabetes and cardiovascular disease, those that adjust for reverse causality by modelling the exposure as change show the opposite association with weight loss and no adverse associations with diabetes or cardiovascular disease. Network and pairwise meta-analyses of randomized controlled trials, which provide a better protection against bias, also show that low calorie sweeteners have the intended benefit when accounting for the calories available to be displaced from the comparator. Comparisons with sugars show the expected weight loss and related improvements in cardiometabolic risk factors while comparisons with water show the expected lack of difference. Overall, the available evidence supports the intended benefits of low calorie sweeteners as being similar to that of other strategies to reduce excess calories from sugars, such as water. More research remains a priority for improving the certainty of the estimates.