Sugar-sweetened beverage consumption and obesity in children’s meta-analyses: Wrong answers to right questions

Abstract

Background: recent studies assert that sugar-containing drinks may play a key role in the etiology of obesity. However, scientific reviews show contradictory results. Whether there is just association or clear causation still is a matter of debate. It is also subject to discussion whether the quality/adequacy of the different studies may influence their outcome. Objective: the aim of this study is to explore the most recent scientific evidence focused on sugar-sweetened beverages (SSB) and child obesity and to further analyze the adequacy of the meta-analyses in terms of their results, with special emphasis in the methodology, clarity and transparence of their procedures. Methods: only meta-analyses of randomized control trial studies were selected. The search was performed on PubMed and Cochrane Website until January, 2016. Adherence to PRISMA statement was assessed. Results: six meta-analyses were included. All of them showed some degree of evidence of heterogeneity in their pool estimates. Two of them showed a positive association between SSB and obesity but the other four found no association. The adherence to the PRISMA criteria was higher in two of the meta-analyses that showed opposite conclusions regarding the association or non-association of SSB and obesity in children. Thus, there is no relation between the adequacy of the meta-analyses to the PRISMA criteria and the results obtained. Conclusion: the use of meta-analysis as a scientific tool still demands more polishing, agreement and spread out use by researchers. SSB are being accused of being the main cause of the existing obesity, and obviously they are part of the problem, but this subject requires a broader approach that includes a thorough analysis of diet and lifestyle and a stronger body of scientific evidence based on data from epidemiological studies conducted in different populations.