Science discovers how your social media strategy might be hurting your sales

In this month’s Marketing Science Cheat Sheet for brands, we explore how brands can improve their social media strategies by optimising for the effect of identity signalling.

The Insight

Consumers generally choose and purchase products that help them to express and reinforce their identity, both externally (to the outside world) and internally (to themselves). This is known as identity signalling.

For example, an individual who considers themselves to be an environmentalist will be able to signal this to others by driving a eco-friendly car.

However, when consumers have been prompted to post about identity-relevant products on social media, this fulfils their identity signalling needs and removes the subsequent need to actually purchase. This can have a harmful effect on brand sales as purchase intent for the same or similar products is reduced.

For the purpose of this study, posting about a product refers to when a consumer comments and shares existing content about a product from the brands profiles on social media or creates their own content using the brand’s promotional material about a product.

The Science

Findings from ‘When Posting About Products on Social Media Backfires: The Negative Effects of Consumer Identity Signalling on Product Interest’ by Grewal et al., 2019, highlight that when consumers post about a product on social media that reinforces part of their identity, this can reduce a consumer’s subsequent purchase intentions for the same and similar products.

This has major implications for product brands using social media marketing strategies that encourage posting and engagement from consumers, as whilst brands may still be able to achieve word of mouth benefits, it could be at the cost of sales from the consumers who are doing the posting.


University of Pittsburgh investigated how posting about products which signalled the consumers identity on social media affected consumers subsequent purchase intentions for the same or similar products. The research was published in the Journal of Marketing Research, a bimonthly, peer-reviewed journal that strives to publish research in marketing and marketing research practice.

Through a series of five experiments, which used a self-report method, the study examined the effect that posting identity-relevant products had on a consumers purchase intention.

The findings highlighted that consumers display less interest in purchasing identity-relevant products after they’ve posted on social media, but that the post must be public in order for this to occur. Interestingly the report also found that consumers didn’t experience a general decline in purchase intention, but rather specifically for the product they used to signal their identity.

Who can benefit

Encouraging consumers to post about products on social media is a popular strategy for brands to help spread word-of-mouth and increase awareness. However these findings indicate that this can backfire on an individual level and therefore effect purchase intention.

These findings will benefit a wide range of brand types, including brands with strong identity associations such as environmental brands like the Body Shop and luxury brands such as Prada, as well as brands with strong social media presence, as this research will help inform future social media strategies.

Opportunities to Create Brand Magic

In order to minimise the effect of identity signalling on social media, the findings of the study suggest that brands could look to update social media strategies to target consumers with private social media accounts. Alternatively, brands could encourage consumers to post about the products usefulness or provide an incentive for consumers after they’ve posted such as a discount, which could help counter the reduced purchase intention.

An example of a brand successfully encouraging its follows on social media to post about products usefulness and/or benefits rather than identity-relevant qualities, is Glossier. The brand encourages consumers to post reviews about its products, focusing on the effect these have rather than promoting the ethical and sustainable qualities, which could trigger identity signalling.

Another way for brands to encourage consumers to engage with the brand is through social media platforms that are more private than Facebook or Instagram. Nike achieved success through Snapchat (a social media platform where only those you follow can see the snaps you share and only for a limited time). The brand used Snapchat’s AR (augmented reality) feature which encouraged fans virtually try on a range of virtual jumpers the brand had created with Nike’s “Just do it” slogan to celebrate the Women’s World Cup. It also let consumers visit the Nike website, where they could buy authentic team merchandise ahead of the tournament.

To encourage consumers to post about a product on social media, brands may create and manage social media competitions that require consumers to comment, share and/or like a post about a dedicated product. However, by doing so when the product is identity relevant, the purchase intent is likely to decline once the consumer has posted and the competition ends. An example of this is Fabletics 12 day competition, which asked consumers to like a post to win a pair of workout trousers. For an extra chance of winning, consumers could also re-post using a dedicated hashtag.

About StoryScience

StoryScience is the UK’s first scientific strategic creative agency. Moving away from the traditional opinion-led approach, StoryScience’s guiding purpose is to pioneer scientific creative and deliver brand magic that audiences want and the results clients need. We deliver creative and strategic marketing solutions underpinned by a scientific creative thinking. In short, we use science to create brand magic.



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