Now that she's on the road with her rapper fiancé Kanye West she is continuing to follow her strict diet and exercise regime.
A source says the new mum has a "trainer on tour with her and Kanye and a chef to keep her meals carb free.
"With the exception of some cheat days, because she is realistic now, she sticks with it!," the insider told PEOPLE Magazine.
"Kim is working out almost every day," the source said. "It's usually running and weight training."
The source added, "It's hard, but she sticks with it pretty much all the time. She's so happy. Life is good."
The 33-year-old recently denied reports that claimed she had undergone surgery to lose her baby weight.
The reality TV star took to Twitter following the publication of a story in Life & Style magazine titled "Weight-Loss cheater".
"I am very frustrated today at seeing reports that I got surgery to lose my baby weight, " she wrote in a lengthy post. "This is FALSE.
"I worked so hard to train myself to eat right & healthy, I work out so hard & this was such a challenge for me but I did it!!
"I'm so proud of my accomplishment & NO ONE will take this away from me with fake reports! Say what u want about me but I work hard & am the most disciplined person u will ever meet!"
At the end of October the TV personality revealed that she had lost 50lbs — 3.5 stone or 22.6 kilos — since giving birth.
It is believed she has lost more weight since then. On 13 October wrote on Twitter that she had been following the Atkins diet, which has a longstanding celebrity following.
Atkins works on the principle that limiting the consumption of carbs forces the body to burn its fat stores to get energy – a process known as ketosis.
Along with rapid weight loss, it promises to regulate your blood sugar and help you achieve optimal health, without leaving you feeling hungry or deprived.