Celebrity Weight Loss: Jessica Simpson, Jennie Garth, Kelly Clarkson

01 of 10

JENNIE GARTH

Divorce threw Garth "for a loop," but it gave the actress a chance to start focusing on herself – inside and out. "A lot of exercising and a lot less eating" helped the former Beverly Hills 90210 star drop 30 lbs. after her March 2011 split from husband Peter Facinelli. "I really feel like that part of me was dead and I need to shed it off," she told PEOPLE. "I decided to start taking better care of myself."

02 of 10

KELLY CLARKSON

Along with a new man, Clarkson got a new look in 2012. "I do cardio. I run. I strength-train using my own body weight," she told Redbook, adding, "[I try] to be healthy and happy."

03 of 10

JESSICA SIMPSON

Following daughter Maxwell's arrival in May, the Simpson found new inspiration to ditch the baby weight. "I want to be as healthy as I can because I'm a mom now," the Weight Watchers spokesperson told Katie Couric in September, showing off her 40-lb. weight loss. "For me, I really want to do something that is a lifestyle, because in the past, I've been known to yo-yo diet."

04 of 10

PAULA DEEN

A Type 2 diabetes diagnosis set the Food Network star on the road to healthy eating – and eventually, a trimmer figure. "It took me a couple of years to get to this point," Deen told PEOPLE of her new attitude towards food, which helped her drop 30 lbs. "If you make a few small changes, they can add up to big results."

05 of 10

GLADYS KNIGHT

Knight walked away from the spring season of Dancing with the Stars with a loss – weight loss! Having implemented a health program prior to the show, the singer went on to shed 60 lbs. during her six-week ballroom stint. "[Partner Tristan MacManus] helped [by] wearing me out," said Knight, who also used Freshology's Getslim with the Stars program.

06 of 10

PINK

For The Truth About Love singer, parting with 55 lbs. of baby weight wasn't a race, but a slow and steady marathon. "It was hard work, and I'm still getting there," she told PEOPLE in September, 15 months after daughter Willow's birth. "I love to feel fit. I love to feel healthy … I'm an athlete so I have to be strong," Pink said of her 90-minute workout program and 1,200 to 1,400 calorie diet.

07 of 10

LISA LAMPANELLI

The comedienne's slim-down proved to be no joke: after 32 years of tipping the scales, Lampanelli turned to gastric sleeve surgery, and lost 80 lbs. "[I thought] 'Nothing's working for me. I'm going to treat this like the addiction that it is. I'm going to get this surgery and use it as a tool,'" she told Dr. Oz during an October appearance on his show. "That's all it is, a tool to help me get over it."

08 of 10

MARISSA JARET WINOKUR

What a difference a year makes! After recommitting to her workout and nutrition routine in January, the actress flaunted her svelte new shape in October, thanks to a simple philosophy: "[I don't] want to eat crap," she said.

09 of 10

KELLY PRESTON

Baby Ben's arrival in November 2010 kicked off Preston's pursuit of getting fit, which saw the actress shed 42 lbs. in 14 months with the help of pal Kirstie Alley's Organic Liaison weight-loss program and two years of breastfeeding. "I'm running after a 2-year-old and keeping up completely!" she told PEOPLE of her newfound stamina. "I think I'd like to stay at this weight. I feel really healthy and I have tons of energy."

10 of 10

CARNIE WILSON

Twelve years after her gastric bypass surgery, Wilson went under the knife again for lap-band surgery last January to help combat the extra pounds she had put on as a result of two pregnancies."It was the right decision for me and I'm doing really well so far," she told PEOPLE in March, at which point she had lost 30 lbs. and counting. "It's all about taking good care of myself."