Which over-the-counter herbal supplements are searched online? A review of internet trends, interest, and lithogenic potential of herbal health ingredients

BackgroundWith the rise in availability of herbal supplements, there has been a similarly expanding landscape of online information about these supplements.Aims/ObjectivesThis study identifies commonly used herbal supplements, their ingredients, oxalate content, and the reliability of their online information.Methods/MethodologyA survey was administered to members of a nephrolithiasis Facebook group on their use of herbal supplements. The top 10 bestselling herbal supplements on Amazon and their common ingredients were identified. Consumer interest and online engagement with these ingredients were analyzed using Google Trends and BuzzSumo. The reliability of the top 10 articles for each ingredient was rated using the DISCERN questionnaire. Oxalate content was quantified by ion chromatography coupled with mass spectrometry.Results/FindingsThe most common ingredients in supplements were black pepper, ginger, apple cider vinegar, and turmeric. Google Trends identified apple cider vinegar, ginger, and turmeric as search terms of high interest. BuzzSumo revealed the highest article engagement and video views for apple cider vinegar. For all ingredients, average DISCERN scores for the most popular articles were in the "poor reliability" category. Turmeric-containing and standalone turmeric formulations were found to have the highest oxalate levels, with ranges of 2.69-54.8 mg/g and 15-19.5 mg/g, respectively.ConclusionsHigh consumer interest in herbal supplements combined with unreliable online information highlights the need for high-quality, evidence-based information. With popular herbal supplements containing varying amounts of oxalate, it may be useful for those providing care for kidney stone formers to familiarize themselves with popular herbal products and their lithogenic potential.