Frozen yoghurt boomed first in America when celebrities such as Paris Hilton were snapped eating little pots of the low-fat snack, and it featured in Sex and the City. Leonardo DiCaprio even had a frozen yoghurt machine installed in his office. Pinkberry and Red Mango were the main pushers of the “fro-yo” trend, but with recent London openings of similar stores it looks as if the fad is set to take off here, too.

It was started by Yogoswirl, a bright shop in Kingston that opened in June and was followed by a competitor called Snog (SNow and yOGhurt) in South Kensington. Both stores say they are places to hang out in with friends, like Starbucks.

“Exactly,” says Snog's co-founder Rob Baines, 43. “I've lived in London for 20 years and have never really found anywhere healthy to sit with friends and relax.” Along with his partner Pablo Uribe, 39, Baines has been running popular Fulham Road coffee shop Tinto for 10 years, so they're experienced in setting up trendy west London hang-outs. And indeed on a Friday evening, Snog seemed to be the meeting place of choice for beautiful, thin Kensingtonians drawn by the thought of fat-free munchies.

I managed to raise the calorie count of my own “little snog” quite considerably by having a cookie with it. Nul points. But the yoghurt itself was delicious, the kitsch little tables and bench outside the perfect place to sit and people-watch.

At both Snog and Yogoswirl, the natural yoghurt is either fat-free (or very low fat) or probiotic meaning it contains live bacteria to assist the digestive system. If you ignore the cookie option and add a fruit topping you've not only got a good protein and calcium hit but ticked the five-a-day box too. It's a snack you can feel virtuous about.

Here's where to try “fro-yo” in London.

SNOG
What's the yoghurt like? Snog offers two types of frozen yoghurt — plain and green tea, both sweetened with natural (and low-GI) agave nectar. The former was lovely and thick, the latter tasted a bit sour. The pots are generously sized and come with a choice of 15 toppings including cookie and brownie. They'll whip up blended yoghurt smoothies too.
Fat and calorie content: the yoghurt is all fat-free and a classic Snog (medium-sized pot) contains 100 calories.
Cost and contact: from £2.85, 32 Thurloe Place, SW7 (020 7584 4926, www.ifancyasnog.com).

YOGOSWIRL
What's the yoghurt like? Only one type on offer here but it was refreshingly tart and came topped with blueberries, strawberries and blackberries. A good antioxidant boost. They are looking to introduce elderflower-flavoured yoghurt soon.
Fat and calorie content: a medium pot contains the tiniest amount of fat (less than 1g) and 93 calories.
Cost and contact: from £1.50,
8 Apple Market, Kingston upon Thames (020 8549 0388, www.yogoswirl.co.uk).

MUFFINSKI'S
What's the yoghurt like? You can choose to blend basic, plain yoghurt with a choice of 15 fruits, but even with fresh mango it tasted a bit like cotton-wool.
Fat and calorie content: a 170ml standard sized pot is 99 per cent fat-free and contains 105 calories.
Cost and contact: from £2.50, 5 King Street, WC2 (020 7379 1525, www.muffinskis.co.uk).

ITSU
What's the yoghurt like? Looks a bit synthetic, like Mr Whippy ice-cream, but tastes delicious — creamy and quite sweet.
Fat and calorie content: the skinny original pot (with no toppings) is fat-free and has 180 calories.
Cost and contact: from £2.79, stores across London (www.itsu.co.uk).

RENDEZ-VOUS
What's the yoghurt like? Sublime, all home-made by twinkly owner Dadu Patel with about 15 fresh varieties to pick from.
Fat and calorie content: the only downfall — it's so delicious because the fat content is the same as ice-cream — 10-14g in each scoop and 250-300 calories. Well worth the guilt, though.
Cost and contact: From £3.75, 48 Leicester Square, WC2 (020 7925 1082, www.rendezvous-leicestersquare.co.uk).