Online information in Spanish on probiotics, yoghurt, kefir, kombucha, fibre and prebiotics: an analysis of the quality of information and the certainty of the evidence supporting health claims

Abstract

ObjectiveTo examine the certainty of the evidence supporting health claims about probiotics, yoghurt, kefir, kombucha, fibre and prebiotics, and to assess the quality of online information in Spanish.DesignContent analysis.MethodsWe compiled a data set of 114 web pages by searching six popular search phrases in Spanish relating to probiotics, yoghurt, kefir, kombucha, fibre and prebiotics on Google.es and coded them for typology and health claims. We examined the certainty of the evidence for health claims from systematic reviews. Information quality was assessed according to 10 criteria, where a web page: mentions scientific publications and reports their conclusions; quantifies relative and absolute effects; acknowledges some limitations; discusses certainty of evidence; reports the potential harms, alternatives and costs; and does not argue based on personal experiences.ResultsGastrointestinal health (86.0%), general health (57.9%), cardiovascular health (53.5%) and immune system health (50.9%) were the most widely mentioned topics. Half of claims (52.6%, 70/133) were supported by evidence from systematic reviews. Probiotics had the highest number of claims supported by evidence and kombucha the lowest. The highest certainty was found for antibiotic-associated diarrhoea, necrotising enterocolitis and otitis (moderate) in probiotics and yoghurt, infectious diarrhoea and hepatic encephalopathy (moderate) in prebiotics, and cardiovascular health (high to moderate) and colorectal cancer (moderate) in fibre. On a scale of 0–10, the median information quality score for all web pages was 3. Only 18.4% reported study conclusions, 7.9% quantified the effects, 28.9% acknowledged some limitations in the research and 42.1% reported potential harms.ConclusionsMost online health claims for dietary interventions intended for improving health through the gut microbiome are supported by low or very low certainty of evidence. Online information does not align with the evidence and is incomplete or unbalanced.

Are popular books about diet and health written based on scientific evidence? A comparison of citations between the USA and Japan

“…Given that several information quality assessment tools evaluate references of information (12)(13)(14) , referencing is considered a minimal requirement for reliable information but does not fully guarantee the reliability of the information. In previous studies, diet health claims extracted from a book, newspapers and websites were evaluated based on the scientific evidence that supported the claims (41)(42)(43)(44) . Although our present study did not evaluate the accuracy of the claims in the books, mainly because each book contained a large number of claims, this is an important area for future research.…”

“…A previous study also showed that some nutrition claims in newspapers were based on evidence with an insufficient grade (43) . Regarding other languages, most online health claims in Spanish to improve health through gut microbiome were supported by evidence described as low or very low certainty of the effect in systematic reviews (44) . Taking these previous and our present results together, books and online information about diet and health may frequently not cite sufficient references and may be supported by evidence with insufficient grade in English as well as in other languages.…”

The individual‐level effects of social media campaigns related to healthy eating, physical activity, and healthy weight: A narrative review

“…Given the widespread interest among nutrition and PA communicators in using social media to reach large numbers of people, it is important to synthesize the available research evidence on the effectiveness of such efforts. Research that supports the dissemination of evidence‐based messages on social media may be especially critical to combat the proliferation of inaccurate or misleading information on those channels 13–16 . Prior reviews have explored the effects of multicomponent diet‐ and PA‐related interventions without evaluating the independent effects of social media components or have examined the effects of intensively moderated, limited‐reach social media programs (e.g., private online discussion boards or social media groups) 4,17–20 .…”

“…Research that supports the dissemination of evidence-based messages on social media may be especially critical to combat the proliferation of inaccurate or misleading information on those channels. [13][14][15][16] Prior reviews have explored the effects of multicomponent diet-and PA-related interventions without evaluating the independent effects of social media components or have examined the effects of intensively moderated, limited-reach social media programs (e.g., private online discussion boards or social media groups). 4,[17][18][19][20] However, no prior reviews have focused specifically on studies testing the independent effects of social media campaigns that promote healthy eating, PA, and healthy weight and do not include intensive moderation that might limit campaign reach.…”