"As overweight and obesity-related health conditions include cardiovascular disease, type 2 diabetes and some types of cancer, it's critical to identify strategies that help facilitate weight loss or weight maintenance," says Vanessa Perez, Ph.D., who presented the study abstract at the annual meeting of Experimental Biology, a multidisciplinary scientific meeting.1,2 "Based on the gold standard study design in medical research -- the randomized controlled trial -- the results show that using low calorie sweeteners resulted in statistically significant reductions in body weight, BMI, fat mass, and waist circumference."
Perez and her colleague, Paige E. Miller, Ph.D., M.P.H., conducted a meta-analysis of published studies dating back to 1976. Meta-analysis, a statistical technique that quantitatively combines the findings from multiple, independent studies, was used to assess the effectiveness of low-calorie sweeteners. The benefits of meta-analysis include a consolidated and quantitative review of large, often complex, and sometimes conflicting body of research.
"Conflicting research on low calorie sweeteners and body weight have led to some debate about the relationship between low calorie sweeteners and body weight," says Perez, a managing scientist at the Center for Epidemiology and Computational Biology, Exponent Inc. "Using meta-analysis techniques, we evaluated 15 randomized controlled trials and nine prospective observational cohort studies to examine the relationship between low calorie sweeteners and body weight and composition."
"Data from the randomized controlled trials indicate that substituting low calorie sweeteners in place of sugar does not cause weight gain and may be a useful tool in helping people comply with weight loss and weight management plans," Perez explains. "The results also show that use of these sweeteners resulted in a modest, but statistically significant, reduction in all outcomes examined, including body weight, fat mass and waist circumference. Additionally, the results do not support recent hypotheses that low calorie sweeteners increase appetite and sweet cravings."
Perez and her colleague also evaluated results from prospective observational cohort studies, which showed inconsistent results. The authors note that these studies are limited and difficult to interpret because few observational studies adequately account for potential factors that could impact the outcome, such as a person's diet and other lifestyle practices.
Perez noted that while past reviews of low calorie sweeteners and weight control have been published, the current meta-analysis is the most comprehensive scientific evaluation to date of low calorie sweeteners and body weight and composition. The complete study has been accepted for publication later this year in the American Journal of Clinical Nutrition (AJCN). This research was funded by the North American Branch of the International Life Sciences Institute (ILSI).