Kirsty Young, who recently took over the role of presenting Crimewatch UK, is supporting the Meningitis Research Foundation's B Aware campaign to raise awareness of meningitis and septicaemia - the blood poisoning form of the disease.
"I contracted life-threatening meningitis in my mid-twenties," says Young. "It was a terrifying experience, but fortunately I made a full recovery. Now, as a mother of two young children, I know just how frightening it is to have a sick child with a high fever and worry that it might be meningitis."
Rita Crowe, Scotland manager at the foundation, says: "I used to work with Kirsty's mother, so when I was at a different organisation I asked if Kirsty could come along to some of our events to raise our profile. She was kind enough to do that.
"Later, while working at the foundation, I saw a press cutting in which Kirsty said that she cared deeply about meningitis but people weren't aware enough about it. Now she's fronting our campaign for 2008."
Sarah Cawood, the television presenter and reporter on Richard & Judy, is among the British Heart Foundation's celebrity supporters to reminisce about their childhood crushes for the charity's Valentine Appeal.
"What can I say about Phillip Schofield and Gordon the Gopher - they're just fabulous," says Cawood. "I had the biggest crush on Phillip when I was younger. One of my main memories as a child is of the broom cupboard on Children's BBC. Edd the Duck just doesn't compare."
Tina Hobley, the Holby City actor, Amanda Lamb, presenter of A Place in the Sun, BBC sports presenter Gabby Logan and WBO World Cruiserweight boxing champion Enzo Maccarinelli also shared their first crushes in support of the appeal, which aims to raise £1m to fund BHF Heart Nurses and its Heart Help Line.
Julie Christie, who has been nominated for the best actress Oscar this month for her performance as an Alzheimer's sufferer in Away from Her, has been named an ambassador for Survival International, the charity supporting tribal peoples. "I've been involved because Survival is fighting against the extinction of many groups of human beings," says Christie,who has supported the charity for more than 30 years.
Ellie Harrison, wildlife reporter on The One Show, is backing BTCV's Spring Into Action initiative. The volunteering charity's campaign, to run between 1 May and 8 June, will encourage people to get involved with environmental conservation. "Join BTCV and you can make a difference to your environment," says Harrison. "You'll be outdoors, getting your hands in the earth, meeting people you might never have met and getting some green therapy - it's an antidote to our stressful lives."
Actor Ralph Fiennes and television presenter Bruce Forsyth are among the famous names who are backing National Doodle Day on 7 March, run by Epilepsy Action and the Neurofibromatosis Association. About 750 celebrities have sketched doodles for the campaign, which raises awareness and funds for the charities.
Indie band Ben's Brother ran a Win a Song competition for the Samaritans' Stress Down Day on 1 February. People submitted stories about how they coped with difficult challenges in their lives. Jamie Hartman, the lead singer, picked a winner on Stress Down Day and will compose and release a song based on their experience.