Britney Spears says she has never been healthier.

The ‘Toxic’ singer, who recently showed off her toned body in a skimpy bikini while on holiday in Mexico, revealed her fantastic new figure is down to a strict high-protein diet.

She told OK! magazine: "I'm the healthiest I've been all my life. My diet has a lot to do with my getting into shape. I have no sugar. I don't eat fruit or even fruit juice because of the sugar. I eat chicken and salmon and rice. I eat avocados. I'll have egg whites for breakfast and sometimes turkey burgers for lunch.

"I try to do just 1200 calories a day. It may sound like it's not much, but it's actually a lot of food if you eat the right things."

Spears has also embarked on a new exercise regime and has been doing “lots of cardio and weights” five times a week.

Meanwhile, it has been claimed the 26-year-old singer is going to try to regain full custody of her two sons, Sean Preston (2) and 23-month-old Jayden James.

Spears is believed to have visited celebrity lawyer Barry Tarlow’s office with her mother Lynne on Tuesday.

She is reportedly determined to get her sons back in the next six to nine months.

Spears currently has two visits and one overnight stay with her children, while her ex-husband Kevin Federline has primary custody.

A hearing has been scheduled for 16 September.

Spears’ custody battle has so far cost her an estimated £350 000 in legal bills.