There are 400,000 people who recommend their favourite supermarket to 25 people every month in the UK, a small but powerful group we're calling 'Grocery Groupies'.
Forget the image of issue-driven, blogger activist, these are predominantly married women with children, a job and a mortgage who are simply more intent on getting a good deal for their families and are far more likely to talk about it.
Waitrose has the highest proportion out of all the grocery retailers of these precious and valuable advocates. In real terms that's 64,000 'Grocery Groupies', the lowest of the big six retailers but the highest in terms of share versus all shoppers.
The opportunity is clear, if retailers like Waitrose can reach these people their message will be amplified 25 times across the personal network of the individual. To tap into this rich vein of advocacy, supermarkets need to get more active in society from community groups, sports events, neighbourhood schemes and voluntary services.
The identification of these super-fans, distilled from shopper behaviour in 20,000 supermarket shoppers using Starcom MediaVest Group's planning application 'Community Igniter' is significant as part of a wider piece of research looking at the changing relationship between consumers and supermarket brands.
What is clear from the research is the real value for brands to create behavioural change within communities and the potential power of word of mouth.
Over the last couple of years we have seen an increase in the importance brands place on community but also a rise in expectation from consumers for companies to give something back to society, a trend set to accelerate.
This change is happening in part due social media that has allowed for the sharing of content - making it easier, more frequent and more natural to give opinions.
In this context, it is now easier for brands to have a direct conversation with consumers who are often very quick to form an opinion. Brands as content creators have the power to create a positive or even a negative opinion very quickly.
Corporate Social Responsibility (CSR) initiatives are very important to this but not in isolation, instead they are part of a wider framework or consumer marketing. Arguably the challenge is to make any CSR initiative distinct and valuable. Sainsbury's are very strong here and Tesco would argue that they are also active in the community.
The best brands make initiatives such as these natural and consistent rather than a blatant attempt to score points. In this sense, it is the effective communication of CSR schemes as much as the scheme itself that matters.
Interestingly it's not necessarily activist bloggers that have the loudest voice, instead it is simply those who are well connected and active in their community. Indeed a 'Grocery Groupie' is 20% more likely than the average person to belong to a community group.
Looking specifically at Waitrose, the proportion of its total shoppers that 'Grocery Groupies' account for is 60% higher than Sainsbury's proportion and 70% higher share than Asda's. Morrisons also does well - with an impressive 179,000 'Grocery Groupies' - the store has over 30% more of these advocates as customers than either of the bigger Sainsbury's or Asda chains.
For supermarket brands specifically, the research points to the power of word of mouth recommendations in everyday, real world scenarios such as mums talking and sharing experiences at the school gates.
Supercharged by social media platforms such as Facebook Twitter, we are getting more vocal at publically sharing both good and bad experiences.
Brand recommendations made in person and online hold equal value and both are set to grow as consumers look to their peers for advice to help cut through the ever increasing choice.
Follow Steve M. Parker on Twitter: www.twitter.com/@steveparkersmg