It's a debate that divides men the length of the nation, but in yoghurt at least, brunette has triumphed over blonde.

Martine McCutcheon's ads for Activia have been credited with driving 22.3% sales growth for the brand to £219.8m [IRI 52w/e 20 February] and, according to Danone, have had more impact than the previous ads featuring Nell McAndrew.

"The recent commercials with Martine are generating more engagement and enjoyment with consumers compared with our previous TV campaigns," said Bryan Martins, customer development controller at brand owner Danone.

Previous Activia ads featured celebrities McAndrew and Jamie Lee Curtis, but Martins said the current Tummy Loving Care campaign had generated above-average consumer recognition and boosted Activia's appeal. "There is increasing demand from consumers seeking foods to improve their health," he added.

NPD such as the introduction of Activia in single pots and the launch of Intensely Creamy had also broadened the occasions when functional foods were eaten, he said. "That stretched the occasion to take functional food away from the traditional morning or lunchtime snack."

Single pots were unveiled in October and have achieved £8.7m in sales, while Intensely Creamy, launched in September 2009, is worth £29.8m [IRI].

The success of Activia comes amid strong sales for the wider functional category, which has risen 4.6% in volume and 5.3% in value to £556.1m over the past year [Kantar Worldpanel 52w/e 21 March].

Sales of cholesterol-lowering Benecol yoghurts have risen 14.2% to £46m, helping the heart sub-category to a 6% hike in value, as consumer awareness of the dangers of high cholesterol grows.

"Consumers are increasingly motivated to take control of their cholesterol and turn to brands they trust," said Benecol Europe marketing manager Esther van Onselen.