In the last few years, the phenomena of overweight and obesity have emerged as some of the most serious global health problems, with consequences on several non-communicable diseases [
1]. Their rate has nearly tripled since 1975: recent predictions forecast that 50% of global citizens will be overweight by 2030 [
2]. In 2016, 1.9 billion people over 18 were considered overweight, whereas in the youngest part of the population, ranging from 5 to 19 years old, 340 million of people were found to be overweight or obese [
1]. In response to this growing issue, governmental bodies (e.g., EU, WHO) have, since 2006, undertaken actions to support consumers in making informed food choices, with the goal of decreasing obesity, and its direct and indirect costs on public health systems.
As a result, numerous member states have begun to develop their own front-of-pack labels (
Table 1) [
4], such as the United Kingdom in 2013 (Multiple Traffic Light), France in 2017 (Nutri-Score), and Italy in 2019 (NutrInform Battery). The introduction of these FOPLs has led to a debate on which label should be adopted for the whole European Union [
5]. These labels follow different—and complementary—approaches, and can be classified, according to the recent EU taxonomy (
Table 1), into nutrient-specific or summary labels [
6]. Nutrient-specific labels present detailed numerical data regarding the nutritional values of foods, specifically on energy value, fat, saturated fat, sugar, and salt, and also through percentages and the usage of colors and symbols. On the other hand, summary labels provide an evaluation of the general healthiness of the product, often through algorithms.
This study aims at further contributing to the European discussion on label adoption, comparing the performance of different FOPLs in two countries with limited evidence on the impact of FOPL on consumers, with specific attention to the pre-usage phase of subjective understanding and liking.
Extant Literature and Research Objectives
Grunert and Wills [
7] modelled the consumer decision-making process regarding food, and outlined the five stages that lead to the use of a product: exposure; perception; understanding; liking; and use.
Among the factors that influence the usage phase, the two different elements that form understanding—objective and subjective—have been deeply investigated by the recent FOPL literature.
Objective understanding is defined whether the meaning attributed by the consumer to the label is in line with the meaning intended by the sender of the label (i.e., if the consumers have understood what the sender wanted to communicate), whereas subjective understanding is the meaning that the consumer obtains from the perception of the information present on the labels (i.e., what consumers believe they understand about nutrition factors relevant to their nutrition knowledge).
Recent studies (
Table 2) compared the performance of different FOPLs along the two dimensions of understanding, and produced on one side, coherent results within each research stream, and on the other side, contrasting evidences and outputs between objective and subjective understanding [
8]. Specifically, summary labels have been shown to be more effective in supporting objective understanding, also due to the use of color, which attracts consumers’ attention, and facilitates decision-making in time-constrained situations [
9,
10,
11,
12]. Recent research [
13] performed in Slovenia confirmed the higher ability of the Nutri-Score to differentiate food products on the basis of composition. A recent study conducted in a Dutch supermarket by Van den Akker et al. [
14] on FOPLs’ effectiveness in guiding consumer choices reported that the Nutri-Score can help consumers toward healthier choices, while not increasing the intended serving sizes.
Studies on subjective understanding have also shown that consumers are able to better understand nutritional values when using a nutrient-specific label, as this kind provides more complete and specific information [
15,
16,
17].
Our research tests two labels that are at the extremes of the EU taxonomy to gain evidence on opposite approaches to FOP labelling: the Nutri-Score, as the most representative summary label at the EU level, and the recently introduced NutrInform Battery. Countries have been selected complementing research already fielded on similar topics [
7,
17], and because they represent very different socio-political contexts.
The Protective Food Logo was introduced in Slovenia in 1992, with the aim to support consumers in their decision-making process toward healthier choices, and to encourage a rework on food formulations [
18]. The logo presents the specific nutrient criteria that a product has to achieve to be able to carry the symbol; in this way, the consumer is implicitly told that the product in question has met specific requirements [
19]. The Protective Food Logo is based on the combination of food-traffic-light thresholds and regulatory criteria for certain nutritional and health claims—the symbol is supported by a specific claim, which presents the benefits of the product [
18]. This symbol can now be found on about 2% of the products on the market, in a context where less than half of the Slovenian population (42%) does not pay attention to food labels [
18]. A study from 2016 made by Miklavec et al. [
20] on the Slovenian Protective Food Logo reported that 78% of the participants had previously seen the symbol, and 64% of them declared to be familiar with it. These results show an increase in familiarity of the symbol among Slovenian adults: the familiarity rate has increased from 40% in 2000 to 64% in 2016 [
20]. This data shows an increased attention of the Slovenian population towards their food intake.
A study by Kupirovic et al. [
18] focuses on the problem of scenarios presenting conflictual information: food can be considered healthy by the symbol, for example the Protective Food Logo, but unhealthy by scoring labels such as the Nutri-Score.
Furthermore, the Nutri-Score has demonstrated to have some blind spots given the fact that some ingredients (e.g., synthetic ingredients) are not taken into account while the main message is that the product should be consumed in reasonable quantities [
21]. In a cross-country study regarding consumers’ understanding of FOPLs, Gregori et al. [
22] reported that front-of-pack labels enhance comprehension, understanding, and interpretation of nutritional information, enhancing consumer comprehension and comfort level with such information. Furthermore, the research concluded that FOP labels encourage food manufacturers to reformulate their products, and develop new products with a healthier composition. Other studies [
23] have shown that in Slovenia, the willingness to pay for products with a front-of-pack label was higher than the average of the other European countries considered. In 2019, however, the adult population in Slovenia was 19.9% obese, and 38.2% was overweight [
24], with a subsequent overall and childhood obesity risk.
The Netherlands recently adopted the Nutri-Score while continuing to analyse the underlying algorithm given the fact that it’s scores are not very consistent with Dutch dietary guidelines [
25]. In 2020, 36.8% of the population was overweight, and 14.2% of the population was obese, increasing since 2002, where the obesity rate was 10.4%, and the overweight rate was 35.3% [
24]. Due to the growing problem of obesity, before the Nutri-Score, the Netherlands adopted the voluntary Dutch Choices label, to indicate a product’s level of healthiness. The Choices label was developed in two different variants: (a) a green logo indicating which are the healthy choices within basic product categories; and (b) a blue logo indicating which are the healthier choices within non-basic product categories [
19]. The results of research conducted by Vyth et al. [
26] reported that exposure to the Dutch Choices label has increased significantly during recent years, and has received different responses according to the customer category. Older, obese respondents reported more need for the logo than younger, normal-weight individuals. Women evaluated the logo to be more attractive and credible than men. Further qualitative analysis has shown that: (a) if the government and scientific authorities were to support the logo, its credibility would improve; (b) older respondents said that, for them, the logo is needed because of health concerns; and (c) consumers who are interested in health use the logo. Vyth et al. in 2010 [
27], in research on the purchasing behaviour of the Dutch population in grocery shops, reported that both participants who are careful about their weight and familiar with looking at nutrition information on food packages would chose products with the Choice label. Van Herpen et al. [
28], who studied the role of familiarity in the evaluation of FOPLs in the Netherlands and in the United Kingdom, highlighted that the level of familiarity with the label influences self-reported evaluations, usage intentions, and healthful choices. Smed et al. [
29], who carried out a study in the Netherlands using household purchasing data, reported a positive effect of labelling for the majority of products. Furthermore, products with the voluntary Dutch Choices label (which indicates that a product is a “healthy” choice) have increased the market share after displaying the scheme [
29]. A study by Egnell et al. [
30] compared different FOP labels (Health Star Rating, Multiple Traffic Light, Reference Intake, Warning Symbols), and tested their impact on the objective understanding of Dutch consumers: the Nutri-Score was found to have the best performance in helping consumers sort foods on the basis of their nutritional quality. Research conducted by Jewell [
19] comparing the performance of FOP labels on the market highlighted that Dutch people were not able to differentiate their Choice Logo with the Green Endorsement Logo: moreover, not all of the manufacturers have participated in the scheme, causing potential confusion on whether the non-appearance of the logo implies product un-healthiness or not. Those results show the need for a label that had greater support from scientific and governmental authorities, and for this reason, in 2021, the Netherlands chose to adopt the summary label Nutri-Score.
In this context, the study has the goal of providing additional evidence concerning the relative effectiveness of two labels at the extreme of the EU taxonomy—NutrInform Battery and Nutri-Score—with the purpose of increasing consumers’ awareness, and helping consumers make healthier choices.
Based on results highlighted in previous research [
15,
16,
17], we expect that, with respect to the three sub-dimensions of “subjective understanding” and to “liking”, a nutrient-specific label (NutrInform Battery) will perform better than a summary label (the Nutri-Score) in both tested countries, Slovenia and the Netherlands.
In particular, we hypothesize the following by considering the three sub-dimensions of subjective understanding (comprehensibility, help-to-shop, complexity):
Hypothesis 1a (H1a). The NutrInform Battery (vs. the Nutri-Score) has a higher impact on the labels’ comprehensibility in Slovenia.
Hypothesis 1b (H1b). The NutrInform Battery (vs. the Nutri-Score) has a higher impact on the labels’ comprehensibility in the Netherlands.
Hypothesis 1c (H1c). The NutrInform Battery (vs. the Nutri-Score) has a higher impact on the labels’ help to shop in Slovenia.
Hypothesis 1d (H1d). The NutrInform Battery (vs. the Nutri-Score) has a higher impact on the labels’ help to shop in the Netherlands.
Hypothesis 1e (H1e). The NutrInform Battery (vs. the Nutri-Score) has a higher impact on the labels’ complexity in Slovenia.
Hypothesis 1f (H1f). The NutrInform Battery (vs. the Nutri-Score) has a higher impact on the labels’ complexity in the Netherlands.
Furthermore, regarding liking, we have hypothesized that:
Hypothesis 2a (H2a). The NutrInform Battery (vs. the Nutri-Score) has a higher impact on the labels’ liking in Slovenia.
Hypothesis 2b (H2b). The NutrInform Battery (vs. the Nutri-Score) has a higher impact on the labels’ liking in the Netherlands.