According to research company Kantar Worldpanel, sales rose 16% in the three months to 12 August - and it believes it is all down to the stars of the hit reality show.
"Love Island not only tugged on shoppers' heartstrings but also their purse strings as men's skincare products jumped by 16%," said Fraser McKevitt, the firm's head of retail and consumer insight.
High street chain Superdrug also saw profits rise 16% to £92.9m for 2017 thanks to its tie-up with this summer's cultural phenomenon, the company said in July.
Products in its "what the Love Island boys will be using all summer" campaign included avocado & Manuka honey shampoo, tan-stimulating sun cream and charcoal toothpaste.
Kantar's latest retail analysis for the 12 weeks to August also showed Britons spent an extra £67m on alcoholic drinks in July during the heatwave.
Consumers' willingness to spend more on products such as ice cream and soft drinks resulted in the growth of branded products outstripping supermarket own-label lines for the first time since May 2015.
"The grocery market experienced strong growth buoyed in particular by the recent heatwave," Mr McKevitt said.
"Over July, thirsty Brits spent an additional £67m on alcoholic drinks, while non-alcoholic beers were cheered on by the sun with sales up 58% compared to this time last year. Soft drinks also increased - up 28%."
Britain's second-largest supermarket group. Sainsbury's, was the worst performer among the country's big four grocers.
Sales rose 1.2%, lagging behind Asda's growth of 2.6%, Morrisons' 2.7% and Tesco's 1.8%.
The Co-op continued to feel the summer glow, experiencing its fastest rate of growth in nearly seven years.
More from Business
US imposes fresh sanctions over Russian cyber attacks
Boost for Chancellor Philip Hammond as UK logs £2bn budget surplus
Manufacturers boosted by weakness of pound - CBI
Scepticism as Venezuela chops five zeros off currency to curb hyperinflation
Families 'living in fear of bailiffs' as household debt level hits £19bn
Liam Fox says the UK can be an 'exporting superpower' exploiting the 'global middle class'
"The last time Co-op saw sales growth of 7.8% it was still benefiting from the acquisition of Somerfield, so its performance is particularly notable this period," Mr McKevitt said.
"Consumers' current preference to shop locally when the sun is shining has helped Co-op attract an additional 263,000 new shoppers through its doors."