The purpose of this paper is to thoroughly assess the value of colours in consumers' preferences for sweet peppers, and the association with more sustainable methods of production in the consumers' minds. Furthermore, this study provides novel insights into the influence of colours on the willingness to pay (WTP) for vegetables. It explores the interplay between colours, food attributes, and socio-demographic characteristics among consumers, marking the first attempt to examine this relationship comprehensively. A discrete choice experiment, based on consumers' preferences for sweet pepper attributes (price, colour, and production method), was implemented and a Seemingly Unrelated Regression model was then applied to evaluate the willingness to pay for different colours. The study has revealed that different colours provide consumers with different utilities and WTP in the choices of potential healthier foods. In addition, gender, age, education and number of family components play a role in affecting consumers' WTP of food linked to colour. Finally, it was found that consumers' knowledge for certain pepper colours with different antioxidant contents is interrelated. This study introduces several novelties, in particular a positive correlation between interest in antioxidants and colours was found, suggesting that interest in healthy food properties might move consumers towards a specific sensory choice.