The X-Men beauty, who is married to actor Jerry O'Connell, gave birth to twin daughters Dolly and Charlie in December, 2008, and she admits it has taken her a while to get back into shape up after becoming ""lazy"" with her eating habits.

She explains, ""I'd gotten very fluffy (fat) for the whole childbearing experience and, you know, you do that when you get pregnant, and then you find out you're having twins and you consume more, and soon you're nursing them for eight months and then you're finishing up their meals, and then I forgot how much I was supposed to be eating and I found out I was eating too much and not really being careful about it.""

Romijn knew she had to change her ways when she found herself feeding her young girls fast food instead of cooking fresh and healthy meals at home.

She says, ""Fast food started making its way into their diet and I felt I was getting lazy about food preparation so... I cut out starch, dairy, sugar (from my diet) for the last few months. It's been hard.""

And Romijn, 38, has also taken on a sweaty new exercise to help her keep trim.

She adds, ""I also took on Bikram yoga, which is hot yoga, for the last year.""