Cynarin is a compound found primarily in artichokes (Cynara scolymus). Its use to support the gall bladder and overall biliary system has both a traditional background in European herbal medicine and some scientific validation. Traditional use includes promoting bile flow and supporting digestion, especially of fats. Modern research has explored these effects, with several studies indicating that cynarin may stimulate bile production (choleresis) and facilitate bile flow, which can assist in the digestion and absorption of dietary fats and may help prevent the formation of gallstones.

A number of preclinical and clinical trials have assessed artichoke extract (which contains cynarin) for its choleretic effect. For example, a randomized controlled trial published in "Phytomedicine" (2002) found that artichoke leaf extract increased bile secretion in healthy volunteers. Another study in "Planta Medica" (1994) demonstrated enhanced bile flow in animal models. However, most studies are on artichoke extract as a whole, not isolated cynarin, and sample sizes are often small.

Overall, while the evidence base is moderate and mainly focused on artichoke extract (with cynarin as a key active), there is scientific support for its use in promoting gall bladder and biliary health, justifying a mid-level rating. More large-scale, high-quality human studies on isolated cynarin would further clarify its specific role.