Shoes with high heels are   fashion choice for many women around   world. However,   new study proves that wearing high heels over   long period of time can permanently injure   body. The study is from Stanford University in   USA. A team of biomotion researchers did tests on   knees of women when they walked in flat shoes, shoes with 3.8-cm heels and in shoes with 8.9-cm heels. The results send   warning to women who want to wear high heels that they risk permanent damage to their knees. They said high heels put knees in   awkward, bent position that makes them function like aged or damaged joints. This increases   risk of the condition osteoarthritis, which could require surgery. Britain's Daily Express newspaper reports   recent survey of 1,200 women that shows how popular high heels are. It said 93 per cent of women say they felt sexier and more feminine when they wore heels, 88 per cent said they considered themselves more stylish and 77 per cent said their heels made them feel slimmer. Many women prefer to ignore health warnings, and even   pain and discomfort of wearing heels, to look and feel good.   British doctor, Tim Allardyce, said he regularly treats women with problems caused by wearing heels. He said: "  odd angle at which   feet are held in high-heeled shoes increases the downward pressure on   knees by 25 per cent, placing significant stress on   kneecaps."