Ad spend in the yoghurt and yoghurt drink category was up 75% year-on-year in the four weeks to 13 December thanks to Danone turning up the firepower behind Actimel and launching a Stay Actiwell campaign.

Over the four-week period it spent an extra £1.5m year-on-year. But Danone was already outspending rivals significantly. In the first 50 weeks of the year, it spent more than £21m [Danone] on press and TV advertising for Actimel, Activia and Shape in an attempt to stimulate growth in a dairy drinks sector it described as "sluggish". Last year, Actimel sales were up 4.3% to £108.1m compared with a 2.6% drop for the total yoghurt drinks sector. [The Grocer Top Products Survey 2008]. By comparison, ad spends for Yakult and Benecol were tiny.

Danone is also targeting different sectors of the population. Since the autumn it has run three TV campaigns - Bobby Charlton promoting Actimel for the grey market, the Stay Actiwell campaign; and now a Nell McAndrew-fronted campaign for Activia.

Bobby Charlton came on board in September to push the health benefits of drinking Actimel daily in a TV ad that ran until 30 November. This week, Bobby returns with a new ad running until the end of next month promoting the message that Actimel helps boost the immune system.

Danone kicked off its Stay Actiwell campaign in the press, on packaging and in-store on 1 November, backing it with a TV commercial from 17 November until the end of December. Press spend concentrated on activity in older women's titles and mid-market and quality papers. Website remains live until the end of next month.

The campaign plays on the recent outbreaks of winter colds and flu viruses by encouraging shoppers to support their defences. The ad directs consumers to the website and a seven-point plan, which includes drinking Actimel daily. There's also information on the immune system, prizes to win and a Morrisons promotion.

Meanwhile, Nell McAndrew is on screen targeting a younger demographic, promoting Activia to those wanting a healthier start to the new year following the festive excesses. A follow-up ad kicks off on 26 January .