Personal trainer and nutritionist Romona Braganza has revealed the secret behind her A-list clients’ perfect bodies.

The sought after nutritionist – who also counts Kate Beckinsale, Halle Berry, Paula Patton and Eva Mendes among her celebrity clients – insists the ‘Sin City’ actress works hard to stay in shape in limits herself when it comes to indulgent treats.

She told the MailOnline: “While it’s fun to occasionally go for fancy diners, have dessert and a glass of wine, it’s equally important to prepare most of your meals during the week.

“Jessica has always enjoyed cooking. She knows that by doing so she can control what goes into her food. She eats plenty of fruits and vegetables and enjoys most dishes.

“Jessica eats only until she is full then puts the fork down.”

Romona also shared the stunning brunette’s strict fitness regime, which focusses on a 3-2-1 training method combining three cardio sessions, two circuit training sessions and one core session.

She explained: “My famous 3-2-1 training method is based on strength training and I always recommend lifting weights to my clients, including Jessica Alba, Halle Berry and most recently Paula Patton, and they still look shapely and feminine.”

Romona stresses the importance of weight-lifting to achieve an “enviably toned” A-list physique and insists women shouldn’t worry about “bulking up”.

She explained: “Women don’t need to worry about bulking up; hormonally women don’t have enough testosterone to look like men.

“Halle Berry, Jessica Alba and Kate Beckinsale all lift weights and none look bulky but instead are enviably toned.”