A new BBC America documentary looks at the cost of extreme weight loss, that "supermodel thin" look that too many women think they want.
In the film, called "Super Skinny Me," two average-size British journalists, Louise Burke and Kate Spicer, agree to a radical experiment -- drop five dress sizes in just five weeks. The goal was to show the drastic and sometimes deadly lengths women will go to just to be thin.
The documentary, "Super Skinny Me," premiers this Sunday at 10 p.m. on BBC America.
Burke, 29, weighed 129 pounds, and had never before tried to lose weight. She turned to magazines for the latest fad diets. One week she drank only protein shakes, another week she ate no carbs -- a week Burke painfully recalled.
"I was just eating watercress soup all day, every day," Burke said.
"My breath smells like soup according to my boyfriend," she said in the movie.
Weighing in at just under 144 pounds, 37-year-old Spicer said she wanted to understand why women go to such extremes to lose weight.
"I believe in journalism," Spicer said. "The best ways to understand something is to become it.''
Spicer followed a radical diet of lemonade with maple syrup and cayenne pepper. She stayed away from solid foods and ran for an hour a day.
Meanwhile, Burke, who began working out with a trainer two hours a day, tried another extreme weight loss tactic.
"Apparently if you swim in freezing cold water it speeds up your metabolism," she said.
In just one week, though, both women saw dramatic results. But the experiment began to take a drastic physical toll.
In the film, Burke described how she had "pins and needles sensation" while lying in bed and how her fingernails turned blue.
She also said she became less productive at work and stopped spending time with her boyfriend.
"My physical appearance, I mean, my ribs. My dad when he hugged me once, he was like, 'Oh my God! I can feel your hip bone and your rib cage,''' Burke said.
Spicer, too, spiraled downward. A dinner out with friends led to bingeing.
"I can't stop eating," Spicer said in the movie. "I don't know if all that hunger has made me eat all of this food in a strange anxious way but it's not right.''
And as she became more obsessed with weight loss, Spicer's binges gave way to purging. Her doctor tells her she will become bulimic if she continues that way.
Spicer was advised to drop out of the experiment a week early, but only after losing a frightening 17 pounds. By the end, she went from a healthy size 12 to a scary size 6.
''Basically I proved that not eating enough makes you go mental," Spicer said.
Burke also said losing that much weight so quickly "sent me into depression really, and I've never been like that before, ever!"
Burke lost 14 pounds over five weeks. Her family and friends were shocked when she could fit into a 6-year-old girl's size zero jeans.
But she was ready to get back to eating real food.
"My boyfriend bought me a massive chocolate cake and I was like, scooping it, clawing it off the tray," she said.
Both women have sworn off dieting and obsessive exercise. Spicer is still working toward finding a healthy balance, and Burke is back to eating everything in moderation.
Asked if she would take part in the weight loss experiment again, Burke said, "No, never! I would never recommend extreme diets again.''