4.1. Research Findings and Implications for Policies
This is the first US study to offer a comprehensive examination of the relationships among celebrities, food and beverage products or brands, and various companies or NGOs that used celebrity endorsements in health-promotion or marketing campaigns. It is also the first study to use the USDA’s Smart Snacks Standards to analyze the nutritional profiles of the food and beverage products or brands endorsed by celebrities in the US marketplace over more than 20 years.
The great number of celebrities involved in the Got Milk? and Milk Mustache Campaigns and the FNV Campaign elevated the number of endorsements for dairy, fruit and vegetable promotion, which might misrepresent the nature of celebrity endorsement used for food and beverage marketing in the US. However, the number of unique brands or products showed that a great majority of the endorsements were for brands associated with SSB, QSR, snacks and candy products rather than for dairy products, fruits and vegetables.
The two interactive dendrograms provide a panorama view of how celebrity endorsements have been used to promote branded food and beverage products and branded health and marketing campaigns in the US from 1990 to 2017. Researchers, civil society groups and government agency stuff could use such comprehensive celebrity endorsement information as a tool to develop policy statements and position papers that call on the industry to use celebrity marketing only to promote healthy food and beverage products.
The nutritional profile evaluation for the food and beverage products and brands supported the hypothesis for RQ2, which found that two-thirds of the brands, endorsements and celebrities were associated with EDNP food and beverage products (e.g., snacks, candy, SSB and QSR foods) that did not align with the USDA’s Smart Snacks Standards. This is a concern because overconsumption of these products is a significant contributor to the obesity epidemic [
3,
4,
48]. We found that celebrities in the US have also been selectively used to endorse healthy food and beverage products such as NCBs and water, or health promotion and marketing campaigns such as the Drink Up Campaign and the FNV Campaign. Some celebrities were associated with both healthy and EDNP product endorsements. When one celebrity is involved in multiple brand or product endorsements, the promotion effects of one brand may spread to others [
49]. Celebrities who endorse healthy nutritional profile products may serve as indirect endorsers of unhealthy nutritional profile products, and vice versa. The results of this study provide evidence for government agencies or other empowered bodies to develop policies to restrict celebrity endorsements that promote EDNP products while encouraging the use of this marketing strategy to promote healthy dietary behaviors.
Statistical analyses of the associations between celebrity demographic profiles and food and beverage nutritional profiles partially supported the second hypothesis in that male and Millennial celebrities were more likely to endorse EDNP food and beverage products than female and Generation Z celebrities. The logistic regression model indicates that male celebrities were 1.5 times more likely than female celebrities to endorse EDNP products. Previous research found that men tend to trust celebrity endorsements more than women [
50,
51,
52]. Men were also reported to be more susceptible to and targeted by EDNP food marketers compared with women [
50,
51,
52]. This result suggests that celebrity endorsement may contribute to poorer diet quality for men than women.
Age was also a significant indicator suggesting that Millennials were seven times more likely to endorse EDNP food and beverage products than Generation Z celebrities. Previous research showed that US Millennials adults are targeted more by food marketing due to their spending power (
$1.4 trillion annually) [
53]. Millennials also spent the highest budget on EDNP products including prepared foods, sugar, sweets and pasta than older generations [
54]. However, Generation Z celebrities only represented 1.8% in the database, and Millennial celebrities were not more likely to endorse EDNP products than celebrities of other generations. Therefore, the results were not strong enough to establish the association between Millennial celebrities involved in EDNP products and the dietary or purchase behaviors of the Millennial consumers. Additionally, no statistical significance was observed to support the hypotheses that Black celebrities and sports celebrities were more likely to endorse food and beverage products and brands did not align with the USDA’s Smart Snacks Standards.
Therefore, we were not able to conclude that the food and beverage companies have intentionally selected Millennial, Black, and sports celebrities to endorse more EDNP products than healthy counterparts, compared with celebrities of other demographic characteristics. However, results from the descriptive statistical analysis for RQ1 found that most Millennial (32.2%, n = 99), Black (33.3%, n = 69) and sports (31.4%, n = 96) celebrities were associated with endorsements for SSB brands and products, which may contribute to over consumption of SSB products among the targeted populations.
Current governmental policies and industry self-regulatory programs have failed to protect Americans from food and beverage marketing [
55]. The Children’s Food and Beverage Advertising Initiative (CFBAI) is an industry self-regulatory program established in 2006 to create more responsible food and beverage marketing practices for children under the age of 12 years. Yet after a decade, the CFBAI has failed to extend its pledges to adolescents, aged 12–18 years, who are targeted by celebrity endorsements of unhealthy food and beverage products [
55]. The federal Interagency Working Group’s voluntary nutrition principles were drafted in 2011 to guide the marketing practices of industry self-regulatory programs [
56]. The principles expended the definition of child-directed marketing up to adolescents aged 17 years but were not approved by the US Congress [
56]. The HER’s responsible food marketing report published in 2015 can be used to guide the industry self-regulatory programs to create a more healthful child-marketing landscape, which suggests that the CFBAI should raise the coverage of their marketing regulations to children aged 14 years and younger [
55]. The National Restaurant Association and Healthy Dining’s Kids LiveWell Program encourages more than 42,000 US restaurant locations to offer at least one healthy children’s meal that aligns with the calorie, fat, saturated fat and sodium recommendations for children aged 12 years and younger [
57]. The USDA’s Smart Snacks Standards are beneficial for a life-long healthy dietary behavior, but these standards are designed to apply up to high school students or those 18 years of age [
13]. There are limited US marketing standards established for young adults aged 18–25 years, who are influenced by food marketing but often neglected as a target population for obesity prevention [
58]. There is a need to harmonize several nutrition guidelines to develop a universal set of standards for food and beverage product marketing to children, adolescents and adults, respectively.
4.3. Implications for Future Research
First, several conceptual models have been widely applied in marketing to explain the influence of celebrity endorsements on people’s decisions and behaviors. However, there is limited research that has applied theoretical or conceptual models to guide the design of studies of celebrity endorsement for food, beverage and restaurant products. For example, it is not known whether celebrities who experience public scandals covered by the media may reduce people’s trust, brand loyalty and willingness to purchase branded food and beverage products endorsed. Future research could use marketing theories or conceptual models to understand the relationships between celebrity endorsement for food, beverage and restaurant products and the diet-related behaviors among targeted populations.
Second, experimental research is needed to understand the influence of celebrity endorsement on people’s consumption of food and beverage products in the US context. Experimental research could be conducted to explore whether racially, ethnically, culturally diverse, and different sex and age groups in the US respond differently to food and beverage products endorsed by celebrities, and which demographic groups are influenced by this marketing practice. It is also important to understand how people think about celebrities who endorse both healthy and unhealthy food and beverage groups and products.
Third, review studies are needed to evaluate the adequacy of the current policies and actions that diverse stakeholders have taken to ensure celebrity endorsement is used to promote products that support healthy food environments.
Finally, there is a need to compile a database regularly and prospectively with more comprehensive and detailed information to evaluate celebrity endorsements used in the US food and beverage marketplace. The database should include the start and end date of the endorsement relationships, the media channels that susceptible populations were most exposed to these endorsements, and the expenditure of using celebrities to promote food and beverage products. This database could be used to explore the shifting trends for the use of celebrity endorsement along the time period and if this marketing strategy is taking an increasing share in food and beverage marketing. The database should be continuously updated to reflect the use of celebrity endorsement in promoting food and beverage products in the US marketplace.