The answer to how ramp models manage to walk in 10-inch heels without tipping over lies in physics.
Safe stilettos seems fairly straightforward: Two parts sacrifice and a dash of solid steel, said Fred Allard, creative director for Nine West, one of the world's largest manufacturers of women's shoes, reports Fox News.
It turns out, there's a formula to avoid tripping in heels: In 2004, researchers at the University of Surrey devised an equation that uses shoe size, the Pythagorean theorem, and several sociological variables to calculate how high heels can safely go.
Variables in the equation include aesthetic appeal of the shoe, experience in wearing high heels, how many months the shoe has been in style, and even the amount of alcohol consumed.
The cost of the shoe plays a factor too, said Dr. Paul Stevenson of the University of Surrey, who developed the equation.
In most cases, five inches seems to be the max, though Allard said Nine West puts no limit on the height of a heel.
But wearing heels comes at a cost. They demand sacrifice: Sacrifice in comfort. Sacrifice in practicality. Sacrifice in stability. Sacrifice in mobility. And in some cases, sacrifice in health, including knee, hip, feet, and back injury, as documented by WebMD.
As for the health risks, the weight of a woman's body is almost entirely focused on a heel the size of a pencil eraser, which creates immense pressure for such a small area. Much more, in fact, than a 6,000-pound elephant-which explains why elephants can walk on grass but women in spike heels can't without sinking into the ground.
That said, heels can also have a positive effect on well-being.
"They have a way of making me feel better about myself," said Dani Gooch, a high-heeled mother of two.
"In that sense, I feel more confident in them than I do in other shoes."