Effects of Milk Thistle Intake on Consumers’ Health Status

Abstract

This study examined the health effects of milk thistle, a widely consumed health functional food in Korea, where demand has risen with increasing incomes and growing interest in personal health. Despite strong consumer expectations, empirical evidence regarding its health benefits remains limited. Using nationally representative data from 2,427 adults aged 19 years and older, we estimated the causal impact of milk-thistle consumption on self-reported health status. Propensity scores were estimated via logistic regression incorporating sociodemographic characteristics, health conditions, lifestyle behaviors, and dietary factors. Propensity score matching (PSM) using nearest-neighbor and kernel matching was employed to estimate the Average Treatment Effect on the Treated (ATT). The results revealed positive and statistically significant effects, with ATT estimates ranging from 0.3320 to 0.3348, corresponding to a 3.32%–3.35% improvement in perceived health (P < 0.01). Subgroup analyses indicated consistently positive effects, with larger gains observed among women, younger individuals, metropolitan residents, and respondents with limited knowledge of health functional foods. In conclusion, the present study provides empirical evidence of modest but meaningful health benefits associated with milk thistle consumption and highlights the importance of evidence-based information in the expanding functional food market. It further demonstrates the utility of PSM as a robust methodological approach for evaluating functional food effects in the situation where randomized controlled trials are not feasible.