The research, conducted by Luigina Canova, Andrea Bobbio and Anna Maria Manganelli of the University of Padua, rests on the Theory of Planned Behaviour, one of the most widely used frameworks in social psychology for explaining voluntary human actions. The theory holds that a behaviour is driven by the intention to perform it, and that intention is in turn shaped by three forces: attitude, the person’s evaluative judgment of the behaviour; subjective norm, the perceived expectations of family and friends; and perceived behavioural control, the sense that one has the means and ability to act. Crucially, the theory also allows for background factors, deeper values and dispositions that feed into these beliefs without acting on behaviour directly.

The Padua team selected two such background factors for scrutiny: the perceived environmental value and the perceived health value of green products. Green personal care products in the study included shampoo, soap and deodorants made from organic farming components free of synthetic pesticides, fertilisers and genetically modified organisms, while green home care products covered laundry detergents, floor and glass cleaners and dishwashing liquids. The market context is striking. The global green personal care market is forecast to grow by 12.37 billion US dollars between 2024 and 2029, and trade in household green cleaning products rose from 5.14 billion dollars in 2023 to 5.49 billion in 2024, with further growth expected to reach 8.49 billion by 2030.

To test their extended model, the researchers ran two parallel two-wave surveys between October and December 2023, distributed through the Qualtrics platform. Roughly one hundred master’s students in psychology at the University of Padua recruited friends, relatives and acquaintances, with each participant assigned to only one of the two studies. In the first wave, respondents answered questions measuring perceived environmental and health values, attitudes, subjective norm, perceived behavioural control and intention. One month later they reported their intention again and, crucially, whether they had actually purchased green products during the intervening weeks. After attrition, the final combined sample comprised 766 adults, 68 percent of them women, with a mean age of 37 years.

The statistical machinery behind the study was rigorous. Confirmatory factor analyses of six latent constructs and twenty indicators produced good fit indices in both studies, and tests for common method variance suggested it did not distort the results. Regression analyses conducted with the PROCESS macro, using bias-corrected bootstrap confidence intervals based on five thousand resamples, tested the direct and indirect pathways of the model, with gender and age included as covariates. The measurement work paid off: the models explained roughly half of the variance in purchase intention in both studies, and between 24 and 28 percent of the variance in self-reported future purchasing behaviour, respectable figures for a psychological prediction of real-world action.

The results were consistent across both product categories in their broad outlines. Perceived environmental and health values each explained about a third of the variance in attitudes toward buying green products, and both fed indirectly into intention and behaviour through the classic Theory of Planned Behaviour constructs. Attitude emerged as the strongest single predictor of intention, followed by perceived behavioural control and subjective norm. But one value clearly outshone the other: perceived health value showed a stronger association with attitude, and in the personal care study it also maintained a direct link to intention, suggesting that consumers who believe green products enhance well-being are especially primed to buy them, partly independent of their general evaluation of the behaviour.

The most theoretically interesting finding concerned the notorious intention-behaviour gap. Meta-analyses across pro-environmental and health behaviours consistently show that intentions explain far more variance in themselves, around 50 percent, than behaviours do, around 30 percent. The Padua team examined whether the temporal stability of intention, measured by comparing intention scores at the two waves one month apart, moderated this gap. It did, and dramatically. For green personal care products, the effect of intention on behaviour was strongest among people whose intentions remained stable over the month, with a standardised coefficient of 0.65, compared with 0.32 among those with unstable intentions. For household products the pattern was even starker: among low-stability participants the intention-behaviour relationship was not statistically significant at all.

Not every result was symmetrical across the two product categories. Perceived behavioural control directly predicted future purchasing only for green home care products, which the authors attribute to the difficulty consumers may face in finding and recognising these items in retail settings, a market that remains smaller than that for green personal care. Demographic patterns also emerged: women expressed more favourable attitudes and stronger intentions toward green personal care products, while women and older participants reported greater perceived control over buying green household products, a pattern the researchers link to gender roles and greater familiarity with household shopping. The authors caution, however, that some indirect effects were statistically significant but small, and should be interpreted carefully.

The study is not without limitations, which the authors acknowledge candidly. The samples were convenience samples dominated by young adult women with medium-high education and income in a culturally homogeneous region of north-eastern Italy, the design was correlational, all measures were self-reported and vulnerable to social desirability bias, and the analyses were not preregistered. Still, the practical implications are concrete. Marketers should emphasise both environmental and health benefits, with certified toxicity and dermatological standards bolstering perceived health value; campaigns should engage family and friendship networks, given the weight of subjective norms; and retailers should improve availability, placement and pricing to strengthen perceived control. Above all, the findings suggest that fostering stable, protected intentions, rather than fleeting enthusiasm, may be the key to converting green goodwill into green purchases, a small but measurable step toward sustainable development goals.

Subject of Research: Psychosocial determinants, including perceived environmental and health values and intention stability, of purchasing green personal and household care products under the Theory of Planned Behaviour.

Article Title: The Purchase of Green Personal and Household Care Products: The Predictive Contribution of Perceived Environmental and Health Values and Intention Stability in the Theory of Planned Behaviour

Article References: Canova, L., Bobbio, A., & Manganelli, A. M. (2026). The Purchase of Green Personal and Household Care Products: The Predictive Contribution of Perceived Environmental and Health Values and Intention Stability in the Theory of Planned Behaviour. Trends in Psychology. https://doi.org/10.1007/s43076-026-00524-9

Image Credits: AI Generated

DOI: 10.1007/s43076-026-00524-9

Keywords: green products, Theory of Planned Behaviour, consumer behaviour, intention-behaviour gap, intention stability, perceived health value, perceived environmental value, sustainable consumption, household care products, personal care products, environmental psychology, Italy