People were invited to share messages of positivity underneath a mural advertising Dwayne ‘The Rock’ Johnson’s tequila brand.
The mural in Shoreditch commemorates the UK launch of Johnson's small-batch 'Teremana' tequila - which translates as 'Spirit of the Earth'.
The Mana Mural is outside Village Underground in Holywell Lane, Shoreditch, until the end of today (July 4). Passers-by have been urged to share messages of happiness and gratitude below it.
Before the unveiling, Mr Johnson said: "The UK is a special place for me.
"To now be able to ‘share the Mana’ with the UK is a privilege."
According to a survey of 2,000 adults, the buzz from performing a good deed lingers for around four hours.
The survey revealed that acts such as holding doors open, accepting neighbours' parcels, and providing directions were most common.
More than 80 per cent of the individuals in the study felt 'positive' after helping others.
Psychotherapist Emma Reed-Turrell said: "Positive social interactions are good for our mental health.
"When we share a positive experience with others, our brains release oxytocin which can promote empathy, trust and relationship-building."
Jonathan Dennys, spokesperson for Mast-Jägermeister UK, added: "We invite everyone to ‘Share the Mana’ by contributing messages of positivity and gratitude to the mural and truly embrace the good spirit of our tequila."
The mural will be available to visit outside Village Underground until the end of the day on Thursday, July 4.
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