The 29-year-old is said to be on a strict diet in a bid to maintain her toned figure - and she wants her team in shape too.
The Hold It Against Me singer has banned them from drinking alcohol.
And she has stopped her boyfriend Jason Trawick, 39, from bringing junk food anywhere near her.
Spears wants to lose 10lbs in a month as she re-launches her pop career.
A source told British newspaper The Sun: 'Dieting's hard for Britney. She and Jason love going to drive-throughs and cooking big meals for the boys like hot dogs with pasta, which is her absolute favourite.
'She's completely turned herself round and won't even allow Jason to eat that kind of food anywhere near her.
'The other day he walked in with a burger meal and she went ballistic.'
The source added: 'Costumes are being designed and millions put into the album. All she wants is to bare a toned stomach.'