Health is one of the frequently mentioned motivations when consumers make their food choices [37, 53]. The term was first coined in Japan in 1994 and functional foods were considered as ‘‘food products fortified with special constituents that possess advantageous physiological effects” [35]. According to The International Life Sciences Institute [3], functional foods are those that include a variety of relevant components to improve health status or reduce the risk (non-prevention) of the disease. When fortified with special constituents, some of the functional foods can not only enhance physiological functions but also reduce disease risks, resulting in improved physical and mental well-being of men and women [36, 52, 39, 45]. Functional foods thus represent an important growth category for the commercial sector in many countries around the world [50]. Diplock et al. [17] gave a widely adopted working definition, which describes a functional food as a food that “affect[s] beneficially one or more target functions of the body, beyond adequate nutritional effects, in a way that is relevant to either an improved state of health and wellbeing and/or reduction of risk of disease.”
The steady increase in life expectancy, the desire of older people for improved quality of their later lives, and the increasing cost of healthcare are the main reasons that explain why there is an increasing demand for functional foods designed to confer health benefits [45–46]. Bimbo et al. [9] estimate the market value for food with health claims at $168 billion in 2013, with an annual average growth rate of 8.5%, and it is forecasted to exceed $300 billion by 2020. Nearly 90% of American adults acknowledge the benefits of functional food. Food companies attracted by this potential have been investing in the development of new nutritionally modified and functional products [32]. In Iran, the demand of functional dairy foods and the opportunities of development on the market seem to be quite favorable and the awareness of the consumers is relatively high.
In addition to the commercial sector, the academic and governmental sectors have also focused on functional food development over the past decade. Numerous studies indicate that consumers are increasingly reflective in matters of health and willingness to adopt health-oriented changes in their eating habits [41, 44, 48]. There are more and more consumers believing that foods contribute directly to their health [40, 62]. However, the absence of a universally accepted definition is one of the major difficulties encountered in assessing the potential health benefits from such foods [10, 38, 27, 47]. Human food choice is a function of a multitude of influences. Such a complex food choice process influences food production systems and consumers’ nutrient intake as it determines what foods consumers buy and eat [19].
Several factors influence the choice of specific types of goods by consumers. Knowing more about these factors and their impact on purchasing choices will help policymakers move towards maximizing consumer satisfaction and boosting the market. The mechanisms of functional food choice are similar to the choice of the so-called conventional food products, but there might be differences in the perceptions of the benefits of using functional foods [56–57]. With recent advancements in modern food science and technology, the food industry can now provide increasingly sophisticated methods for controlling and altering the physical structure and the chemical composition of a food product.
Functional foods promise improved health, better well-being, or enhanced functioning of physiological processes. The importance placed on one’s health is correlated with the intention to purchase functional foods [55]. Consumers’ beliefs in the health benefits of functional foods constitute an important factor affecting acceptance of these products [58]. Therefore, people concerned about their health should be more interested in functional foods [23].
Increasingly affluent and ageing populations have become more concerned with protecting their health through diet. Consumers’ acceptance of the concept of functional foods and a better understanding of its determinants are widely recognized as key success factors in successfully negotiating market opportunities and consumer-led market orientation [2, 21, 24, 58, 59, 61]. As a consequence, there is a growing number of studies addressing cognitive, motivational, and attitudinal determinants of consumers’ acceptance of functional foods and/or their willingness to use them in different countries [7–8, 16, 22, 30, 31, 34–43, 56–57–58].
However, none of these studies examined all the attitude components simultaneously. Moreover, there is a research gap regarding the context of Iran as all these studies were carried out in other countries (e.g. Hungary, Italy, Germany). This research analyses the impact of different attitude components on the consumption and acceptance of functional dairy foods in Iran, taking into account all the known components in previous studies and using the structural equation approach.
Despite much research into functional foods, not all people in a community are prepared to accept these foods. It is important to investigate whether or not local consumers with varying levels of health consciousness and contradictory healthy lifestyles will have diverse attitudes toward functional foods and will differ in their willingness to use for functional dairy products. The findings are hoped to provide some recommendations to the marketing agents in the functional dairy foods industry to develop marketing strategies and facilitate these products consumption in the society.
Therefore, this study investigated the prominent attitude components affecting the consumption of functional dairy foods among urban Iranian consumers. The functional dairy foods used in this study were as follows:
(1) Milk enriched with vitamin D. Vitamin D is a fat-soluble bioactive vitamin, which is sensitive to light, heat and oxygen [6].
(2) Probiotic yogurt. Probiotic yogurt is among the most popular probiotic products [33, 54]. Nowadays, probiotics are included in many products in order to promote the growth of probiotics consumption. Therefore, incorporation of probiotics into fermented milks such as yogurt, especially those containing probiotic bacteria, would potentially lead to a healthier product. It is argued that prebiotics may aid survival of probiotics in fermented milks during processing and storage [11].
(3) Probiotic cheese (Cheddar cheese). Cheddar cheese may offer certain advantages over yogurt-type products in terms of delivery of viable probiotics, such as the reduced acidity of the cheese compared to yogurt environments and the high fat content and texture of Cheddar cheese may offer protection to the microorganisms during passage through the gastrointestinal tract (GIT) [51].