Sustainable marketing and green consumerism: how eco-labels influence purchase decisions in fast-moving consumer goods – a systematic literature review

Abstract

This study examines the influence of eco-labels on consumer purchasing decisions within fast-moving consumer goods (FMCG) markets, utilising a systematic literature review that integrates psychological, signalling, and institutional perspectives. Systematic review, conducted under the preferred reporting items for systematic reviews and meta-analyses (PRISMA) 2020 protocol, of 52 high-quality peer-reviewed studies (2010–2025) from Scopus, Web of Science and Google Scholar. Thematic synthesis and meta-regression were conducted within a multi-level contingency framework. Eco-label effectiveness is context-contingent, varying by institutional trust regime: confirmatory cues in high-trust contexts (β ≈ 0.62), persuasive information in moderate-trust contexts (β ≈ 0.35–0.42), and discounted claims in low-trust contexts (β ≈ 0.12). Institutional trust appears to operate as a foundational gating condition: below an indicative threshold, Theory of Planned Behaviour (TPB) mechanisms weaken markedly. Choice architecture interventions – defaults, placement, and framing – were associated with effects approximately 2.6–3.0 times larger than those of attitude-focused strategies. Greenwashing exceeding roughly 30% was associated with markedly weaker effects (by a factor of about 6.5×), a pattern consistent with legitimacy tipping points. This review advances a unified multi-level framework integrating TPB, Signalling Theory, and Legitimacy Theory, specifying boundary conditions for each. Its contribution is integrative – reorganising existing evidence to explain heterogeneous outcomes within established theories – rather than the proposal of a fundamentally new theory. It offers indicative thresholds for policy intervention and a structured research agenda. The framework offers diagnostic tools for context-contingent sustainable marketing strategies.