BRITNEY SPEARS - SPEARS ORDERS PHOTO TOUCH UPS

BRITNEY SPEARS begged designers to airbrush photos for her upcoming world tour - because she looked too fat in them.

The ONYX HOTEL TOUR snaps reportedly featured the singer looking bloated and chunky, until they were digitally slimmed down to resemble her trademark svelte body.

And Britney's personal trainer BOBBY STROM has exposed several sources behind her fluctuating weight, including her mum LYNNE's home cooking.

He says, "Her mind has not been in the right place for working out. She's had lots of stuff to get sorted in her head and her personal life lately. But I think that she's over it and back on course, mentally and physically. I'm sure I'll be seeing her again soon.

"She's fond of her mum's food but it tends to be carb heavy and calorific. I've told her to cut out barbeque sauces and gravies, and eat more protein - especially on tour. She also needs complex carbs such as brown rice, veg and wholegrain breads."

A source tells Britain's STAR magazine Britney, 22, was devastated by her appearance in the photos, and complained to her promoters, "I look like a blimp, so do something about it. I need to look perfect - better than perfect."