Uma Thurman reportedly "eats whatever she likes" and doesn't deny herself any treats.
The Hollywood actress gave birth to daughter Luna last June and has since refused to diet.
Instead, sources say Uma - who is a UK size 12 - credits eating slowly and keeping hydrated as the reason she is looking svelte post pregnancy.
"Uma eats whatever she likes, but she makes sure she has a pint of water before a meal and eats slowly. She stops before she feels full, because she says it takes 20 minutes for your brain to recognise that your hunger's been satisfied," a source told British magazine Closer.
"And she stays hydrated, as sometimes your brain thinks you're hungry when you're actually thirsty. If she craves chocolates, she has it, but just one or two squares."
Uma is currently dating financier Arpad Busson, but also has children Maya and Levon from her marriage to Ethan Hawke.
The 43-year-old star apparently struggled to lose the 3st she gained while pregnant with the newest family addition, but prefers to spend time with her brood rather than obsessing over her diet and fitness regimes.
"Uma found it very hard to lose the baby weight and in the end decided she wanted to focus on bonding with her baby over working out like a maniac," the source added to the publication.
"She'll do yoga if she has time but, with three kids, it's very hard!"
Uma proudly paraded her bikini body as she relaxed in St. Tropez recently.© Cover Media