Mariah Carey has been unveiled as the new spokesmodel for the Jenny Craig diet plan after using the firm's meal plans to shed 30 pounds (13.6 kilograms) of baby weight.

The pop superstar gave birth to twins in April (11) and turned to advisors at the weightloss company in July (11) for help in speeding up her slim-down.

She tells USA Today, she felt a "kinship" with everyone she worked with at the firm - because they had all struggled with their own weight issues, and she credits the healthy eating programme for helping to get her curvy pre-baby figure back - and making her feel great.

She says, "I feel better in every way... I was in a bad place physically during my pregnancy."

The new Jenny Craig TV adverts will feature a new Carey song titled Make It Happen and the tune means a lot to the new mum.

She adds, "I wrote that song from personal experience. (The song is) so fitting because a lot of people give up hope when they have had their kids and can't lose that 20 pounds or 40 pounds, or they have gone through issues with weight their entire lives. It becomes so frustrating and debilitating that you give up."

Carey has lost a total of 70 pounds (31.75 kilograms) since becoming a mother.

She follows in the footsteps of Star Wars actress Carrie Fisher as a Jenny Craig spokesmodel. Kirstie Alley and Valerie Bertinelli have also previously fronted the brand.