Beyond the Eco-Label: How Credibility Shapes Sustainable Food Choice Online

Eco-labels are important information cues for evaluating the environmental attributes of food products online, yet their effectiveness depends on whether consumers perceive these claims as credible and decision-relevant. This study examines how perceived food eco-label credibility shapes sustainable food purchase intention through two complementary cognitive mechanisms—perceived diagnosticity and perceived value—and whether these processes are contingent on food traceability and price sensitivity. Survey data were collected from 496 consumers of Hema Fresh, a major Chinese online grocery retail platform, and analyzed using structural equation modeling, bootstrap mediation analysis, and moderation analysis. Eco-label credibility positively influenced perceived diagnosticity (β = 0.415, p < 0.001) and perceived value (β = 0.417, p < 0.001), which subsequently increased sustainable food purchase intention (β = 0.372 and 0.295, respectively; both p < 0.001). Bootstrap results confirmed significant indirect effects through perceived diagnosticity (effect = 0.154, 95% CI [0.099, 0.215]) and perceived value (effect = 0.123, 95% CI [0.075, 0.179]). Food traceability strengthened the effects of eco-label credibility on both perceived diagnosticity (β = 0.215, p < 0.001) and perceived value (β = 0.103, p < 0.001). Price sensitivity weakened the perceived diagnosticity–purchase intention relationship, whereas its moderation of the perceived value–intention relationship was not significant. These findings reveal how credible eco-label information is translated into sustainable food choice through complementary information-diagnostic and value-evaluation processes, while identifying traceability and price sensitivity as distinct boundary conditions in online grocery retail.