If you have ever watched a beauty tutorial by someone with a few thousand Instagram followers and felt the urge to try the product they were using, you are not alone. Brands, especially smaller ones, are increasingly turning away from big-name celebrity deals and toward social media personalities with smaller but highly engaged audiences. A new study published in Marketing Intelligence & Planning investigated whether these so-called micro-celebrity endorsements actually influence how young consumers feel about a brand and whether they intend to buy the endorsed product. The short answer: they do, and the single most important factor appears to be how much the micro-celebrity interacts with followers.
What exactly is a micro-celebrity, and why should marketers care?
A micro-celebrity is someone who has built a fan base primarily through social media rather than through traditional channels like television, film, or music. These individuals tend to have smaller audiences than mainstream celebrities, but their followers often feel a closer personal connection to them. That sense of closeness comes from a key difference: micro-celebrities frequently reply to comments, host live chat sessions, and engage in back-and-forth conversations with their audience.
For brands, this dynamic is appealing for two reasons. First, micro-celebrity endorsements typically cost far less than deals with mainstream stars. Second, product recommendations woven into a micro-celebrity’s regular content may feel less like advertising and more like a suggestion from a trusted friend. But while the marketing industry has embraced this approach, research has been limited on whether micro-celebrity endorsements actually move the needle on brand attitudes and purchase intentions, and which specific traits of these endorsers matter most.
The question the researchers set out to answer
Ruchi Gupta, a professor at Shaheed Bhagat Singh College in New Delhi, India, led a team of researchers that included Kiran Nair of Abu Dhabi University, Seema Bhardwaj of Middlesex University Dubai, and Justin Paul of the University of Puerto Rico. They wanted to know two things. First, does a micro-celebrity’s endorsement of a product on Instagram have a significant link to followers’ brand attitudes and their intention to purchase the product? Second, which specific attributes of the micro-celebrity endorser are most strongly associated with those outcomes?
Prior research had established frameworks for evaluating traditional celebrity endorsers, focusing on traits like attractiveness, trustworthiness, and expertise. But the researchers argued that these models were incomplete for the micro-celebrity context. The missing ingredient, they proposed, was “engagement level,” a term they used to describe the degree to which a micro-celebrity interacts directly with followers through live chats, comment responses, and interactive conversations on social media.
How the study was designed
The team collected data from 435 young women in Delhi, India, all aged 17 to 25 and all followers of Shirley Setia, an Instagram micro-celebrity. Setia had endorsed Maybelline eye pencils on her Instagram account, and each respondent watched a video of that endorsement before completing a questionnaire. The product, a cosmetic eye pencil, was chosen because it is considered a low-involvement purchase, meaning consumers do not typically spend a lot of time deliberating before buying one. This made it a useful test case for whether a micro-celebrity’s endorsement could shift attitudes even for everyday products.
The questionnaire asked respondents to rate the micro-celebrity on five attributes using a seven-point scale, with one meaning “strongly disagree” and seven meaning “strongly agree.” Three of the attributes, attractiveness, trustworthiness, and expertise, came from an established scale developed by researcher Roobina Ohanian in 1990. A fourth attribute, relevance, came from a model called PATER, which assesses how well a celebrity endorser fits with the product being endorsed. The fifth attribute, engagement level, was new and defined by the research team. It was measured through three specific items: whether the micro-celebrity does live chat sessions with followers, reacts to comments on social media posts, and engages in interactive dialogue.
Respondents also answered questions about their attitude toward the Maybelline brand and their intention to purchase the product. The researchers used a statistical technique called structural equation modeling, or SEM, to analyze the relationships between the endorser’s attributes and the two outcomes they were measuring: brand attitude and purchase intention. Before running the main analysis, the team validated their measurement tool using confirmatory factor analysis, a method that checks whether survey questions actually measure what they are intended to measure.
What the numbers revealed
The results showed that a micro-celebrity endorsement on Instagram was significantly linked to both brand attitude and purchase intention. In statistical terms, the standardized beta coefficient for brand attitude was 0.35, and for purchase intention it was 0.28, both significant at the 95 percent confidence level. Put simply, respondents who viewed the micro-celebrity’s endorsement tended to feel more positively about the brand and were more inclined to say they would buy the product.
When the researchers broke the analysis down by individual endorser attributes, the findings were particularly interesting. All five attributes were significantly linked to brand attitude. Engagement level had the strongest association (beta of 0.33), followed by attractiveness and relevance (both 0.30), trustworthiness (0.19), and expertise (0.15).
For purchase intention, four of the five attributes showed significant links. Engagement level and attractiveness tied for the strongest association (both 0.27), followed by relevance (0.21) and trustworthiness (0.16). The one exception was expertise: the micro-celebrity’s perceived knowledge about cosmetics did not have a statistically significant link to whether followers intended to buy the product. Its beta value was just 0.07, which did not reach the threshold for statistical significance.
When the researchers looked at which attributes were most important in defining a micro-celebrity endorser overall, engagement level ranked highest with a beta value of 0.95, followed by attractiveness (0.80), trustworthiness (0.71), expertise (0.66), and relevance (0.65). This ordering suggests that what sets a micro-celebrity apart from a traditional celebrity endorser is precisely this interactive, conversational quality.
Why expertise did not seem to matter for buying intent
One of the more notable findings was that expertise, or the perception that the micro-celebrity had real knowledge about the product, was not significantly associated with purchase intention. It was linked to brand attitude, but not to the next step of actually wanting to buy. This may seem counterintuitive: you might expect a follower to be more likely to purchase a product if they believed the endorser truly understood it. But in the context of a low-involvement product like an eye pencil, expertise may matter less than how engaged and relatable the endorser feels. The researchers did not test higher-involvement products like electronics or financial services, so it is possible that expertise would play a larger role in those categories.
What this means for businesses and marketing teams
For marketers, the study’s findings point to a few practical considerations. The data suggest that when selecting a micro-celebrity for a product endorsement, brands should prioritize candidates who are actively engaged with their followers rather than simply choosing the most attractive or well-known person. Live sessions, comment responses, and genuine two-way conversations appear to be associated with stronger brand outcomes.
This could be especially relevant for small and medium-sized businesses operating on tight budgets. Micro-celebrity partnerships are a fraction of the cost of traditional celebrity deals, and the study suggests they can still generate positive associations with the brand and increase consumers’ stated willingness to buy. For larger companies, micro-celebrity endorsements could serve as an additional channel to reach specific consumer segments, particularly younger demographics who are heavy social media users.
The researchers also suggest that brands consider forming long-term partnerships with micro-celebrities rather than one-off deals, as sustained collaboration may reinforce authenticity in the eyes of followers. Selecting a micro-celebrity whose personal values and content align with the brand’s identity is another recommendation, since a perceived mismatch could undermine trust.
Important limitations to keep in mind
There are several caveats worth noting. The study focused on a single product category, cosmetics, and a single platform, Instagram. Results might differ for other types of products or on platforms with different dynamics, such as TikTok or YouTube. The sample consisted entirely of young women aged 17 to 25 in Delhi, India, so the findings may not apply to other age groups, genders, or cultural contexts.
The study also relied on a nonprobability sampling method called judgmental sampling, where the researchers selected participants based on their relevance to the research topic rather than through random selection. This means the sample may not be representative of all young female Instagram users, even within India. Additionally, because the study measured associations rather than running a controlled experiment, it is not possible to say definitively that the micro-celebrity endorsement caused changes in brand attitude or purchase intention. Other unmeasured factors could have played a role.
Finally, purchase intention is not the same as actual purchasing behavior. Saying you intend to buy something and actually pulling out your wallet are two different things. While prior research has shown a general link between the two, the gap between intention and action is real and worth remembering when interpreting these results.
Still, the study adds a new variable to the conversation about what makes influencer marketing work: the degree to which the endorser actually talks with, not just at, their audience. For businesses navigating a crowded social media environment, that interactive quality may be worth paying attention to.
