Fears that wearing high-heeled shoes could lead to knee arthritis are unfounded, say researchers.
But being overweight, smoking, and having a previous knee injury does increase the risk, the team from Oxford2 Brookes University found.
They looked at more than 100 women aged3 between 50 and 70 waiting for knee surgery, and found that choice of shoes was not a factor.
The study was published in the Journal of Epidemiology and Public Health.
More than 2% of the population aged over 55 suffers extreme pain as a result of osteoarthritis of the knee.
The condition is twice as common in 65-year-old women as it is in men the same age.
Women's and men's knees are not biologically different, so the researchers wanted to find out why twice as many women as men develop osteoarthritis in the joint4.
Some researchers have speculated that high-heeled shoes may be to blame.
The women in the study were quizzed on details of their height and weight when they left school, between 36 and 40 and between 51 and 55.
They were asked about injuries, their jobs, smoking and use of contraceptive hormones5.
However, while many of these factors were linked to an increased risk over the years, tottering6 around in high heels for years was not.
The researchers wrote: "Most of the women had been exposed to high heeled shoes over the years - nevertheless, a consistent finding was a reduced risk of osteoarthritis of the knee."
There was an even more pronounced link between regular dancing in three-inch heels and a reduced risk of knee problems.
The researchers described this finding as "surprising", but said that they would not expect a larger-scale study to overturn their findings.