Information trustworthiness is a fundamental segment of integrated communications by health food industries, especially in the currently rapidly growing category of health food products. Namely, the global trend of health food products has achieved popularity in the Republic of Croatia mostly due to certain functional values which aim to satisfy the targeted public regarding health-related aspects. In addition, the targeted public’s perception and their decisions to purchase the aforementioned products are not solely affected by health factors, but also include environmental issues and issues pertaining to the society as a whole, i.e. its overall sustainability. Therefore, the credibility of health food products’ image relies heavily on new sustainable trends whose goals and principles stipulate the products in question do not negatively impact society and the environment. This paper aims to theoretically and empirically analyse information trustworthiness for the category of health food products on the Croatian market, as well as their communication pertaining to sustainability, whilst relying on the three principles of sustainable development. The research method used was content analysis of sales packages of health food products by select private green brands from specialized health food stores. The content analysis has shown that sales packages of health food products frequently do not emphasize their primary purpose in relation to functional values for the targeted public in health-related aspects. Furthermore, despite certain certificates being used on sales packages, the general sustainability of products in respect to their provenance, cultivation conditions, manufacturing methods and distribution, as well as their recyclable (compostable) sales and transport packaging cannot be verified, since the targeted public has no insight into information concerning traceability. Accordingly, the trustworthiness of said products is evident solely through the targeted public’s trust in certificates and sales package labels, i.e. through the trust they lay in the manufacturers who in turn implement them on their products.