Fun in the sun: Love Island’s sexy recipe leaves Häagen-Dazs in the cold

But we shouldn’t be surprised. Sex always has, and always will, sell. It’s how you package it that’s changed.

For many, Love Island is a guilty pleasure, adored by young and old across the class divide, just like ice cream.

Even the critics have fallen for this fun in the sun frolic that had the nation on tenterhooks last night as it came to a climax. The bookies’ favourites Kem Cetinay and Amber Davies took the crown – and £25,000 each, watched by an estimated three million fans.

The Telegraph called it the biggest TV night of the year. It was live blogging the final along with the Guardian. The Radio Times and Mirror were in there, too, but you know it’s a big event when broadsheets go live.

This sunny delight reworking of Big Brother is beating the actual Channel 5 show hands down with its bunch of twenty-somethings actively encouraged to get it on in their holiday island villa.

The Love Island formula has seen ITV2 buck the wider decline in younger viewers in spectacular fashion. The number of 16 to 34-year-olds watching has increased by 86%.

It’s a millennial hit that should make Häagen-Dazs think again. The company once used a slew of provocative ads from Bartle Bogle Hegarty that made eating ice cream an “orgasmic experience”.

Until, that was, a recent focus group found that sex no longer sells to millennials. So out went sexy suggestion and in came fully clothed models enjoying their ice cream with not a messy sheet in sight. But could Häagen-Dazs have misread the runes?

PwC research in 2016 may have shown that nearly half (47%) of shoppers in this age group said they had changed their eating habits towards a healthier diet, but that doesn’t mean they’ve lost their appetite for sex.

Love Island has everyone loved up. Cosmopolitan online has just been gushing over one of last year’s studs, saying Alex Bowen is: “the fittest person on Instagram.”

While this show continues to spawn a new generation of stars, established celebrities are clamouring to confess that they’re fans. Liam Gallagher, Stormzy – even Jeremy Corbyn each happy to admit watching the show.

It’s the talk of the chattering classes. The BBC, rather truculently, asked: "Love Island: What’s the big deal?" The Financial Times discussed how the big news was that Camilla had finally "done it" with Jamie. The Observer quizzed: “How can reality TV ever top Love Island?”

Until the final, Love Island’s highest average audience this year was 2.1 million viewers. That’s massive for ITV2 and a big jump from last year’s 1.3 million. Then there’s catch-up, taking viewer numbers up to 4.5 million.

As Kelly Williams, ITV’s managing director of commercial, explains: "It’s just hit the zeitgeist.”

An incredible 65,000 young people applied to be on this year’s series, up from 16,000 last year – all presumably happy to have sex on a TV set covered by 72 cameras to make sure we catch all the action.

And if the media seems obsessed with rationalising the phenomenon as a guilty pleasure, perhaps that’s because it’s driven by women who make up 67.4% of the viewers, 63.6% of them under 35.

Elizabeth Day wrote in Telegraph Women about "Falling for Love Island – an accidental affair (and one you should have too)." She admits she’s addicted.

So are marketers as online searches for headline sponsors Superdrug surged by 900% during the past month. Other brands have been cashing in wherever they can in a veritable feeding frenzy.

The fact is more and more women are stepping into what we thought was male-dominated territory, and tereotypical male and female gender roles are being redefined.

Pornhub released data on International Women’s Day this year that shows 26% of its users are women and 80% of them access their services on a smartphone or tablet. That’s 23 billion visits, 64 million a day and 92 billion videos.

And if you still have doubts about sex selling, another massive hit this summer makes the point. Love it or hate it, Despacito has become the most streamed song of all time with 4.6 billion plays.

Its catchy tune, raunchy lyrics and hot video alone might have been successful for Puerto Rico-born Luis Fonsi and Daddy Yankee. Add the pulling power of Justin Bieber in a remix, though, and the world became their oyster.

So don’t think for a minute that our innate interest in sex is on the wane. If anything, it’s waxing as women take control and become more open about what they enjoy.

It’s not the sole preserve of reality television, either. Aidan Turner’s topless turns as Ross Poldark got people hot and bothered up and down the land and did the BBC’s ratings no end of good.

Where’s that ice cream to cool you down when you need it?