By reducing energy density, low-energy sweeteners (LES) might be expected to reduce energy intake (EI) and body weight (BW). To assess the totality of the evidence testing the null hypothesis that LES exposure (versus sugars or unsweetened alternatives) has no effect on EI or BW, we conducted a systematic review of relevant studies in animals and humans consuming LES with ad libitum access to food energy. In 62 of 90 animal studies exposure to LES did not affect or decreased BW. Of 28 reporting increased BW, 19 compared LES with glucose exposure using a specific ‘learning’ paradigm. Twelve prospective cohort studies in humans reported inconsistent associations between LES use and body mass index (-0.002?kg?m(-)(2) per year, 95% confidence interval (CI) -0.009 to 0.005). Meta-analysis of short-term randomized controlled trials (129 comparisons) showed reduced total EI for LES versus sugar-sweetened food or beverage consumption before an ad libitum meal (-94?kcal, 95% CI -122 to -66), with no difference versus water (-2?kcal, 95% CI -30 to 26). This was consistent with EI results from sustained intervention randomized controlled trials (10 comparisons). Meta-analysis of sustained intervention randomized controlled trials (4 weeks to 40 months) showed that consumption of LES versus sugar led to relatively reduced BW (nine comparisons; -1.35?kg, 95% CI -2.28 to -0.42), and a similar relative reduction in BW versus water (three comparisons; -1.24?kg, 95% CI -2.22 to -0.26). Most animal studies did not mimic LES consumption by humans, and reverse causation may influence the results of prospective cohort studies. The preponderance of evidence from all human randomized controlled trials indicates that LES do not increase EI or BW, whether compared with caloric or non-caloric (for example, water) control conditions. Overall, the balance of evidence indicates that use of LES in place of sugar, in children and adults, leads to reduced EI and BW, and possibly also when compared with water.
This systematic review and meta-analysis examined the role of low calorie sweeteners in appetite control, energy intake and body weight, and for this scope it analysed the available data from 90 animal studies, 12 prospective cohort studies, 129 comparisons in short term experimental studies, and 9 long term RCT’s. Overall, a fairly consistent picture emerged; low calorie sweeteners in beverages may contribute to a lower energy intake and body weight. The authors conclude “We found a considerable weight of evidence in favour of consumption of low energy sweeteners (LES) in place of sugar as helpful in reducing relative energy intake and body weight, with no evidence from the many acute and sustained intervention studies in humans that low energy sweeteners increase energy intake. Importantly, the effects of LES-sweetened beverages on body weight also appear neutral relative to water, or even beneficial in some contexts.”