Melissa Joan Hart has no plans to wear bikini again: 'At a certain age it's inappropriate'

Melissa Joan Hart has been busy the last few years. Starring in “Melissa & Joey," and raising three young boys with her rocker husband, Mark Wilkerson. But these days there has been a lot less of the 38 year-old star to see: She recently lost an impressive 40 pounds. Hart explained to FOX411 how she was able to shed the weight and why you won't see her in a bikini anytime soon.

FOX411: You lost 40 pounds!
Melissa Joan Hart: Yeah, I had put on way too much weight, baby weight. I tend to get very big with my kids. I'd been using pregnancy as an excuse to let myself go. After always being disciplined in Hollywood and in my youth it was easier to get the pounds off, but then after having three kids it just got more and more difficult. And I always let myself go a little too much during pregnancy so after the kids were born there was a bit of work to do.

FOX411: What was your “aha” moment?
Hart: I just knew I had to get back to work. I was getting older and not wanting to take the time to take it off. I just made the decision to do it. While I was pregnant I started researching different pregnancy plans and also started researching workout I could do. I talked to friends, “What are you guys doing? When do you go walking? When do you go to spin class?” I started looking into that stuff because I was done being big and heavy. Once I lost the normal baby weight, the extra 30 pounds, what you're supposed to put on, then I began to lose the rest of it.

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FOX411: So how did you do it?
Hart: I started with Nutrisystem once I weaned the baby. The weight started coming off pretty quickly. I could eat my mac and cheese while I fed the kids their mac and cheese. It kind of jump started me. Once I started seeing the weight come off, I started to move a little easier, breathe a little easier, keep up with my kids a little more. I started getting compliments and then last summer I was able to fit in jeans I haven't been able to fit in since I had babies.

Now my body's been on a burning kick. I'm eating right for myself. I can enjoy workouts once in a while but it's not all about workouts; 80 percent is my diet. Now I don't have to feel stuffed to be satisfied. I can still eat ravioli just not an entire serving of ravioli or what Americans think is a normal serving of ravioli.

FOX411: American servings have gotten huge.
Hart: Enormous! Now I have one slice of pizza instead of three. And I've decided that if I'm going to have a slice of pizza it's going to be the pizza I like and it's going to be hot. It's not like, “Look what I got my hands on! I'm going to eat every bit of it.” I feel great now. I have so much energy. I'm able to keep up with my kids. I can go snowboarding, go on the trampoline with them.

Best of all my husband notices my body. I have to do it for him in some sense. He takes care of himself for me so I have to return the favor. I would say to my husband, “Why do you work out so much?” and he would say, “For you! Who else is it for?” He does it for himself but he does it because he wants to look sexy for me.

FOX411: Some people think that's old-fashioned but it's actually kind of respectful to your partner.
Hart: I'm the kind of girl who likes to be natural and not wear any makeup. But I realized he wants me to look my best so I'm going to cover my zits, put a little concealer under the eyes, a little powder and a little mascara. I'm not going to put on a full face of makeup in the morning but you know, maybe fix myself up in the morning. Brush my hair before I come downstairs. Why not take care of myself? The thing is the time commitment is so minimal.

FOX411: Will you be wearing a bikini this summer?
Hart: I much prefer a one piece at my age. But I'll definitely be in a bathing suit. I just feel like at a certain age it's inappropriate at the beach.

FOX411: You're only 38!
Hart: I know. I see women in their 60s in bikinis. I don't know. I don't have any. That took me a lot of guts to put that on [for the Nutrisystem ad]. It was a little nerve wracking for me. I'm also not a sun worshipper. I like to be covered up. I'm pale, I'm Irish. I think that's one of the secrets of why people say I haven't aged. I haven't really been in the sun. I'll be there but with a big hat.