Influencer Marketing Symposium 2025: Why smaller voices make the biggest impact

Insights from the Data & Insights Network – and what it means for the future of brand building

By: Lisette Kruizinga – de Vries (DVJ Insights) & Linda van Rijn (YouGov), Jury Members Insights Scientist Award 2025 

On May 22, the Data & Insights Network hosted its annual symposium, “The Value of Influencers for Building Brands,” at De Balie in Amsterdam. The event brought together researchers, marketers, and creatives to address a timely question: How can brands maximise the value of influencer marketing in 2025?

With influencer marketing now a core part of many brand strategies, the conversation has moved forward. Do mega influencers still deliver results? Are micro- and nano-influencers more trustworthy? Can AI-driven influencers create genuine emotional connections? And how can brands make the right choices?

Here’s what we learned:

Influencer marketing: Hype or brand-building essential?

Karen Sweere, Senior Brand Manager at Unilever (Zwitsal), opened the event with a direct question: Is influencer marketing still a trend, or has it become essential to brand growth?

Her answer was clear. Brands must adapt. Through practical examples from Unilever’s “social-first” strategy, Karen showed how the balance of control has shifted from marketers to creators. Today’s marketing is about many-to-many communication. Brands are no longer just sending messages out to the masses; they are building communities.

To succeed, brands need to be authentic. They need to know who they are, who their community is, and how to create meaningful content that speaks to them. Testing and learning are key, and flexibility is essential. 

Choosing the right influencer: What the data says

Eva van Reijmersdal, from the University of Amsterdam and the first nominee for the Insights Scientist Award, shared findings from two studies that examined how brands can select the right influencer.

She focused on two main elements: audience size and the influencer’s public persona. The research showed that smaller influencers often have a stronger impact because their followers see them as more relatable and trustworthy.

The way an influencer presents themselves also plays a role. When they act as opinion leaders, audiences view them as experts, which can benefit the brand. Presenting oneself as a regular person can also be effective, as it supports credibility and social appeal.

From influence to impact: What drives sales?

Martijn de Kemp, founder of Storyboard Agency, explored how influencer marketing influences purchasing decisions. His agency’s research found that credibility, trust, sincerity, and authenticity matter far more than the number of followers.

In 2022, 61 percent of consumers followed influencers. By 2025, that number has jumped to 85 percent. But people don’t buy just because someone popular told them to. They respond to content that aligns with their interests, tells a believable story, and feels natural, even while clearly showing the brand.

Martijn also noted that repetition strengthens effectiveness, just as it does with traditional advertising.

Measuring ROI: What delivers the best return?

Second award nominee Andreas Bayerl, from Erasmus School of Economics, shared his research from a widely downloaded Journal of Marketing article. His team examined the financial value of influencer marketing using a database of influencer posts, follower comments, and sales activity.

His key finding was that micro- and nano-influencers outperform macro-influencers. These smaller influencers generate more conversions while being more cost-effective. They are also more in tune with their audience, often using the same language and tone, which helps build stronger connections.

Can AI influencers be authentic?

Herwin van den Berg from the agency Endeavor shared his experience working with influencers since the early days of the industry. He reminded us that influencing is not a new concept. Long before social media, people were already influencing one another’s choices in classrooms and communities.

Now, with digital tools and AI, the scale is much larger. Herwin explained that today’s focus is more on quality than quantity. The follower count is becoming less relevant. Influencers are increasingly acting like salespeople, with content serving as the primary driver.

His team has also worked with AI influencers like Gabriela for Vredestein. While AI offers complete brand control, the brand eventually stopped using her, unsure how audiences truly felt about engaging with a virtual figure.

Can AI be believable?

Third award nominee Lotte Willemsen, from Hogeschool Rotterdam and the University of Amsterdam, has been exploring this question from the start. She was involved in creating Esther Olofsson, the first Dutch AI influencer, and her research focuses on whether people can form emotional bonds with virtual figures.

The answer is yes. This occurs through a psychological process known as anthropomorphism, where we attribute human traits to non-human entities. Even when people know that an influencer is AI-generated, they can still form emotional connections. While real humans are still more relatable, the gap is not as wide as many assume it to be.

She emphasised the need for clear rules about influencer marketing. Audiences must be aware when they are being targeted with advertisements, and regulations need to keep pace with the rise of virtual personas.

Key takeaways

This year’s symposium left no doubt about it. Trust, credibility, and authenticity are what matter most in influencer marketing. Smaller influencers consistently outperform their larger counterparts in both building relationships and driving results.

As AI influencers become more common, the need for transparency and ethical standards increases. The Netherlands has already taken steps, including the creation of influencerregels.com, which introduces certification requirements for influencers.

Whether you’re working with humans or AI, the most successful influencers are those who come across as genuine and authentic. Choose carefully.

*This blog was originally posted on Data & Insights Network (datainsightsnetwork.nl)