She was in Glasgow today to launch Wee Box, Big Change, the annual Lenten fundraising campaign of Catholic development agency SCIAF.

The campaign invites people to put the money they save from giving up that bar of chocolate or cup of coffee into a savings box and donate it to the charity come Easter.

The money raised will go towards the charity's work supporting communities in Haiti that are still recovering from a major earthquake there in January 2010.

Other stars backing the campaign include Scotland football captain and Manchester United player Darren Fletcher, Harry Potter actress Katie Leung, singer songwriter Eddi Reader, broadcasters Kaye Adams and Sally Magnusson, and Charlie and Craig Reid of The Proclaimers.

Speaking at the launch, Boyle recalled a Wee Box being in her home during Lent because her parents were big supporters of SCIAF.

She said she was giving up sweets and chocolates for Lent.

"I know every penny they get will be used in practical ways to help poor people support themselves in the long term so they can fulfil their own dreams of a future with respect and human dignity," she said.

SCIAF Chief Executive Paul Chitnis said the campaign would make a huge difference to the people SCIAF works with in poor countries.

“We are absolutely thrilled that Susan has joined us today and that so many other high profile Scots are taking part in this year’s campaign," he said.

"I’ve no doubt their public support will encourage many more people across Scotland to find out about the campaign and join in.

"By making a small change in our own lives such as giving up chocolate or wine for Lent and donating the money to SCIAF, you can really make a big difference to people in poverty overseas.”