New mum Gwyneth Paltrow has reportedly started a gruelling diet in a bid to shift her baby weight.

The Sun reports the A-lister - who welcomed son Moses in April - has turned to her long-term health guru Dr Nish Joshi for help in getting her figure back.

The mum of two has enlisted the help of renowned health guru Dr Nish Joshi, whose other clients include Sadie Frost, Nicole Appleton and super-skinny Kate Moss.

The pair apparently met in New York last month to get Gwynnie started on the eight-week regime, which will see her throwing out all wheat, dairy, sugar, gluten, red meat and alcohol.

Instead, the blonde will apparently stick to turkey, chicken, white fish and vegetables.

A source close to the Oscar winning actress and wife of Coldplay's Chris Martin said: ¡°Gwyneth is really testing her willpower with this one. She has followed a macrobiotic diet for years and has only recently relaxed the rules so she can have some dairy products. But now Dr Joshi has listed everything she can and cannot have in order to get back to her pre-baby physique - and it's scary.¡±

The Oscar-winner has apparently been turning to tight corsets to make her look slimmer before the results of her new eating plan kick in.

"Gwyneth has been wearing corsets to make her appear thinner but she can't wait to bin them when the diet is finished," said the source.