mariah-carey.jpg Mariah Carey, 36, is eating purple foods such as red grapes and beetroot — three days a week because of their anti-ageing benefits.

A source said: “It sounds off-the-wall but it’s a huge injection of healthy food in one go. Purple products are nature’s best weapons in the battle against ageing. There’s a saying that ‘a plum a day keeps a facelift away’.”

Mariah Carey reportedly sat down with her nutritionist to plan the diet. The diet includes foods high in anti-oxidants and vitamins.