By Kimberly Papa Wolfson
Wynonna Judd
This country crooner has been the spokesperson for alli, the only FDA-approved over-the-counter weight loss pill, since January 2009. Judd has struggled with her weight since she was 9 years old and has said that alli helps her make healthier lifestyle choices. Since beginning the program she's gone down two dress sizes. But alli is no weight loss wonder drug. Side effects include oily spotting, loose stools and hard to control stools. The FDA is also currently investigating reports of liver damage in patients taking alli.
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Kim and Khloe Kardashian
These reality star sisters are known for their curvy figures. Kim has spoken about how much she loves enjoys working out and has cut down on sugar to maintain her famous curves, while Khloe credited her recent 20-pound weight loss with five-day-a-week workouts and eating a healthy balanced diet. But it turns out hitting the gym and kicking bad eating habits aren't the only ways the Kardashians lose weight. The sisters endorse a line of diet supplements called QuickTrim. It includes "Extreme Burn" pills, which claim to burn calories 300 percent faster and contain caffeine. Research has not shown that caffeine significantly or permanently helps people lose weight, but it can have dangerous side effects, including increased heart rate, blood pressure, insomnia and anxiety.
Kim has said "Using Quick Trim helped boost my metabolism and jump start my weight loss," and Khloe later confessed that her dramatic 20 pound weight loss over the course of four weeks was the result of using QuickTrim. Like most other diet products that offer rapid weight loss, QuickTrim is not FDA approved.
Joe Kohen, WireImage
Carmen Electra
There's no denying that former "Baywatch" babe Carmen Electra has an amazing body. While you might think Carmen has great genes and good surgeons to thank for her rockin' curves, the Playboy Playmate once claimed the NV weight loss pill, for which she was the spokesperson, was what helped her maintain her figure. NV, which is no longer on the market, called itself the "world's first rapid weight loss beauty pill," and contained green tea extract and the stimulant theobromine.
Arlene Richie, JPI Studios
Anna Nicole Smith
Former Guess? model and Playboy Playmate of the Year Anna Nicole-Smith had plenty of weight loss highs and lows in her lifetime. Her once-enviable body was noticeably heavier when her reality TV series "The Anna Nicole Show" debuted in 2002.
In 2004 she became the spokesperson for the over-the-counter-diet drug, TrimSpa. Smith never went on record about how much she weighed, but did say she lost 69 pounds taking Trimspa. While Smith acted as the face of TrimSpa, two class-action lawsuits were filed accusing the manufacturers of misrepresenting the ingredients and effects of the pills.
Three years after shedding the weight, Smith died of an accidental overdose in 2007. Autopsy results revealed that Smith's system contained methadone, anti-anxiety and weight-reducing drugs and, possibly, vitamins, among other substances.
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Britney Spears
After years of eating Cheetos, having babies and hard partying, it looks like the pop princess finally has her banging bod back. While regular dance rehearsals for her Circus tour and a healthier lifestyle are likely the reason behind Brit's transformation, Fox News recently reported the singer may be taking diet pills as well. According to the story, Spears has been caught popping diet pills, such as appetite-suppressing Dexatrim, and washing them down with Red Bull before performances.
Frank Micelotta, Getty Images
Petra Nemcova
Model Petra Nemcova, who has graced the cover of Sports Illustrated's swimsuit issue, admitted that in order to stay skinny in the past, she has taken laxatives. "I went through so many diets in my life. I've been very, very skinny. I've been a size zero but I'm naturally more curvy," she told People. "I went through all of it just to be able to model."
Astrid Stawiarz, Getty Images
Natasha Henstridge
The "Species" vixen wowed the world with her killer body in the sci-fi movie, but Henstridge admits that she went to extreme lengths to get her incredible physique. "There's always pressure in this business to stay thin to the degree that I've done some things that probably weren't the smartest things in the world...I've probably taken some pills that are taken off the market these days, that were like, 'Oh, but it just gives me an extra boost when I'm working out,' and it seems innocent enough and it's over the counter," Henstridge revealed to People. Today, Natasha has ditched the diet pills and embraces her curvier figure. She stays active with hikes and trapeze classes.
Denise Truscello, WireImage
Carre Otis
Carre Otis began modeling at the age of 15, but keeping her frame pin-thin drove Otis to take extreme measures including starvation, drugs and diet pills. By the age of 30 Otis suffered a seizure and needed heart surgery as a result of malnutrition. She was 5'10 and weighed just 100 pounds. Today, Otis is healthy and embracing her fuller figure (a size 12) and working as a plus-sized model.
Lester Cohen, WireImage for Hollywood Reporter
Trista Sutter
Former bachelorette Trista Sutter shed 30 pounds just five months after giving birth to son Max thanks to a strict diet, four-day-a-week workouts and a diet supplement called Revolution Abdominal Cuts, she said in an interview with Us Weekly. Unlike many diet pills, the ones Sutter took didn't contain appetite suppressing stimulants, but a blend of oils like CLA and sesame oil.
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Candace Cameron Bure
Sitcom sweetheart Candace Cameron revealed to Us Weekly that she felt she was "chubby" as a child. Cameron told the magazine, "When I was 16, I filmed an episode of "Full House" where my family goes to Disney World. I remember putting on baggy overalls just to hide my stomach. When I watched it, I was pretty disappointed and bummed out looking at myself...I didn't feel good about my own body."
Although Cameron tried a healthy diet plan, when she didn't see results she turned to diet pills and "stuff like that, which never worked." She admitted, "You try bad things here and there." Cameron's weight yo-yoed until last year, when the 5'2 mom of three revealed she had shed 22 pounds on her own by changing her eating habits and exercising.
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Spicy foods have been shown to kick your metabolism into high gear, but what if your taste buds can't take the heat? The maker of a new weight-loss supplement, called Capsiplex, claim that they've put all the calorie-burning benefits of chili peppers -- minus the spice -- into a pill. 
