Kim Kardashian
Kim Kardashian flaunted a slim figure at her 31st birthday party in Las Vegas in October. CeleBuzz.com

As New Year's approached, many chose lose weight as their resolution for 2012. Whether or not that resolution has been upheld is another story.

Sticking to a diet and exercise plan is often a difficult task. Motivation may be tough to come by; a decent regimen may be even tougher to come by. What inspire are success stories from those who have pushed themselves to reach goals and achieved them. Celebrities are the perfect emblems of possibility. If they can do it, you surely can to (even if you don't have a personal trainer on call 24/7).

Here are some weight loss-victories from 2011 that will inspire you to hit your target mark in 2012.

Snooki

Snooki, star of MTV's reality series Jersey Shore, was lovingly known as a meatball, but the jabs eventually got old. I love food. I love drinking, boys, dancing until my feet swell. I love my family, my friends, my job, my boss. And I love my body, especially the badonk, she has said. But by the end of Season 2, Snooki looked in the mirror and was shocked. She asked herself, What the hell happened to me? Now, Snooki, who stands at 4-foot, 9-inches, is a slender 98-pounds.

How did she drop the weight? In June 2010, Snooki tried Dr. Siegal's Cookie Diet. She also noted that she cut down on her alcohol intake. If I go out I am going to have a drink, but I am not going to have 10 drinks like I usually would, she said. In September 2011, the pint-sized diva announced that Zantrex-3 diet pills were her newest weight loss secret. She said The first time I took it, I went to the gym, and I was walking on the treadmill for an hour, and I wasn't even tired. Snooki said that she saw visible results in a short period of time.

Kim Kardashian

Kim Kardashian is famous for her curves. But the reality star has slimmed down her figure in recent months. I'm proud of my body and my curves and this picture coming out is probably helpful for everyone to see that just because I am on the cover of a magazine doesn't mean I'm perfect, she said.

How did Kim tighten up her curvaceous frame? Changing my eating habits makes a big difference, Kardashian told Us Weekly magazine. I wake up and eat eggs with turkey bacon, then salad for lunch and fish, pasta or chicken for dinner. Kim eats more organically these days and even downs wheatgrass shots from time to time. Work-outs are necessary. The E! star trains with Gunner Peterson. Every minute is accounted for, said Peterson. You go from running to pull-ups to lunges to crunches to overhead presses. You get more work done in the same time.

Miranda Kerr

This supermodel gave birth to her first baby boy, Flynn, in January 2011 and was ready to strut down the runway in the showcase lingerie Fantasy Treasure set at the Victoria's Secret Fashion Show in December. Miranda Kerr is looking more gorgeous than ever. Her Victoria's Secret campaigns were chosen as the No. 2 Sexiest Ads of the Year. Ad Age called her fabulous and said It's like she's never been away.

What's her secret? Although Kerr says breastfeeding helped, she also credited Tahitian Noni Juice, a drink made from the noni plant, and coconut oil for her healthy body, according to The Daily Mail. I've been drinking it since I was 14, and when I've got a long day ahead of me, it's the one thing I can't live without, said the Australian stunner. Manufactures claim the drink supports your immune system, delivers superior antioxidants, increases energy, and allows greater physical performance levels. Kerr also reached for coconut oil every day. 'I personally take four tablespoons of coconut oil per day, either on my salads, in my cooking or in my cups of green tea, she said. Her exercise regimen included yoga.

Mariah Carey

Mariah Carey gave birth to twins, Moroccan Scott and Monroe, in April and has already lost more than 30-pounds. The 41-year-old singer is back and looking better than ever.

How did the pop icon shed the baby weight? She chose Jenny Craig. Mariah is now the brand ambassador for the company and promotes her weight loss in a new television ad campaign, singing her hit Make it Happen while wearing a black thigh-split skirt and bandeau top. The Jenny Craig program is based on three levels - eating right and keeping portions small, increasing energy levels and building life balance to maintain a target weight. Carey spent three months on a 1,200-calorie-per-day plan and is now a size-6.

Jessica Alba

This young mama just gave birth to her second daughter, Haven, in August and already looks slim and trim. Photos of her vacationing in Cabo revealed Alba's svelte physique. The 5-foot, 7-inch beauty lost all of the baby weight in just three months.

How did she do it? Is she superhuman? Alba told Us Weekly that she has 1,200-calorie meals delivered to her. I have a hard time with portion control, she explained. She combined this regimented diet with 90-minute workouts four days a week. The plan got back her pre-baby body in no time.

Jordin Sparks

Jordin Sparks, who hit the American Idol stage at just 17-years-old and claimed the crown, admitted to being self-conscious of her body. I like to wear sleeves because they cover up my arms, she told People magazine in 2007. Now, Sparks flaunts a size-8 figure after having dropped 30-pounds. I wore Spanx! she exclaimed. I was so excited!

How did Sparks get her body into shape? She ate smaller portions - opting for one serving of sweet potato casserole instead of two -- and enrolled herself in Zumba classes, the popular Latin dance-inspired cardio class. She also went on hikes and tried 30-minutes of high-impact cardio. I feel good! I love that I still have my curves. I definitely didn't want to lose those, she says, adding, I don't want to lose more weight. I just want to tone. I'm in a really good place now.

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