Health- and fitness-conscious individuals worldwide go for artificially sweetened beverages (ASBs) over their sugar-sweetened counterparts (SSBs), however the health benefits of ASBs remain debated throughout the scientific community. In a recent umbrella review published within the journal Benefits in Nutrition, researchers examined the outcomes of previous systematic reviews and meta-analyses to confirm the credibility of medical and ASB-industry-funded research to judge whether AIBs truly meet the health gains that their manufacturers market. Their findings from 11 meta-analyses and 7 systematic reviews indicate that frequent ASB consumption can result in a better risk of obesity, all-cause mortality, hypertension, type 2 diabetes (T2D), and heart problems (CBD), contrary to current consumer belief.
Review: Artificially Sweetened Beverages and Health Outcomes: An Umbrella Review. Image Credit: VTT Studio / Shutterstock
What are AIBs?
Artificially sweetened beverages (ASBs) are beverages containing sucrose-replacing sweeteners, including saccharin, sucralose, neotame, and advantame. Since they contain little to no conventional sugar (sucrose), they’ve little calorific value and are marketed as healthier alternatives to traditional sugar-sweetened beverages (SSBs). These drinks are trendy amongst health- and fitness-minded individuals and people chubby or obese based on the belief that fewer calories, all else being equal, is healthier than more.
Recent medical research has challenged these assumptions, with a growing body of literature suggesting that ASBs could also be linked to rapid unwanted changes within the gut microbiome and related to increased all-cause mortality risk. Alarmingly, some studies have reported ABSs as contributing to cancers and heart problems (CVD), while others have found no such association. These conflicting medical reports are further complicated by industry-funded research, most of which provides ASBs their approval as secure for human consumption.
Umbrella reviews are a novel class of reviews that summarize and evaluate the outcomes of previous reviews and meta-analyses while also verifying the technical and scientific soundness of the methodology and analyses that led to those results. They present a great technique of cutting through the fluff, especially when multiple scientific reports suggest starkly contradictory outcomes (healthy versus not healthy) of the identical treatment (ASB consumption).
In regards to the study
The current umbrella review goals to look at the understanding of claimed health outcomes as a consequence of ASBs and discover potential biases or inconsistencies within the literature. This review further evaluates the methodologies employed in previous reviews and meta-analyses each as a test for credibility and to tell future authors of the perfect practices to make use of when conducting ASB-health studies.
This study adheres to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) 2020 guidelines. Data was collated from three publication repositories, PubMed, Embase, and the Web of Science, from their inception until 25 May 2022. Inclusion criteria comprised all systematic reviews, meta-analyses, cohort, and case-control studies testing the associations between ASBs and health. Nevertheless, cross-sectional studies were excluded as a consequence of the inherent weakness of evidence the study design suffers from. Results from systematic reviews comprising mixed study designs (cross-sectional alongside others) were filtered to remove the cross-sectional results, with the remaining results reanalyzed.
Collated data included the primary writer’s name, the 12 months of study publication, PECO (population, exposure, comparison group, end result), exposure and end result variables, and effect sizes. Moreover, the funding source of studies, each the meta-analyses and their constituent publications, were recorded.
The A MeaSurement Tool to Assess systematic Reviews (AMSTAR) tool (specifically AMSTAR-2) was used to judge the methodological soundness of included studies. The tool comprises 16 items that guide researchers in verifying the standard of systematic reviews.
“1) use of PECO elements in the outline of goals and methods of the review, 2) adherence to a well-developed study protocol, 3) justification of the number of study designs, 4) use of a comprehensive literature search strategy, 5) study selection in duplicate, 6) data extraction in duplicate, 7) provide an inventory of excluded studies and justification, 8) description of included studies in adequate detail, 9) proper technique used to evaluate risk of bias of included studies, 10) reporting of the sources of funding of chosen studies, 11) appropriate methods for statistical analyses of the meta-analysis, 12) results of risk of bias assessments were considered in meta-analyses, 13) results of risk of bias assessments were discussed, 14) the sources of statistical heterogeneity were discussed, and 15) publication bias was assessed and discussed.”
A random-effects model using the bottom study-specific ASB consumption as a standardization parameter was used to estimate the typical effects of every ‘high-quality’ systematic review to check the results of inter-study heterogeneity. This was then in comparison with results from a fixed-effects model assuming an absence of inter-study heterogeneity. Inconsistency between studies was computed using I2, a metric that presents the quantity of variability in effect results as a consequence of heterogeneity somewhat than study sampling error. Egger’s test was used to compute slight study effect bias.
The initial repository sweep identified 7,218 publications, of which 68 met inclusion criteria following title and abstract screening—of those 68, full-text screening and the exclusion of cross-sectional studies resulted in seven systematic reviews and 11 meta-analyses reporting PECO that were included within the statistical pipeline.
Collectively, the included studies reported the associations between ASB consumption and 13 health outcomes. Of those, present study analyses revealed that high- and regular ASB consumption depicted a positive association with CVD risk, CVD-associated mortality, chronic kidney disease, obesity, all-cause mortality, hypertension, T2D, and pancreatic cancer. Following AMSTAR assessments of the studies reporting these findings, nonetheless, the association between ASBs and CVD-associated mortality, chronic kidney disease, and pancreatic cancer was found to be weak and inconclusive.
Dependable study results revealed that sucralose and saccharin utilized in most ASBs have a rapid and severely detrimental impact on the human cardiovascular system, impairing glucose tolerance in hitherto healthy adults following only two weeks of day by day ASB consumption. Human and animal studies further showed that some artificial sweeteners stimulate immune inflammatory responses within the gut wall.
“Results obtained with the AMSTAR-2 tool indicate that almost all authors of systematic reviews aren’t making use of predefined study protocols, which can increase the danger of creating unfounded decisions during all of the stages of the systematic review. Moreover, all reviews didn’t add information of the sources of funding of the literature reviewed. The Cochrane handbook for systematic reviews of intervention recommends to look at closely the conflicts of interest of lead and corresponding authors, based on information reported in the current or previous publications and even searching in additional databases.”
- Diaz, C., Rezende, L. F., Sabag, A., Lee, D. H., Ferrari, G., Giovannucci, E. L., & Rey-Lopez, J. P. (2023). Artificially Sweetened Beverages and Health Outcomes: An Umbrella Review. Advances in Nutrition, 14(4), 710-717, DOI – https://doi.org/10.1016/j.advnut.2023.05.010, https://www.sciencedirect.com/science/article/pii/S2161831323003150