According to venerable Herald Square retailer Macy's, the average woman changes bra sizes at least SIX times in her lifetime. Similarly, Macy's also says that most bras wear out or lose their basic function in just six months. No wonder your shoulders hurt.

In a study undertaken by Sidney Ross Singer and Soma Grismaijer, women who wore a bra 24 hours a day revealed a 113-fold increase in breast cancer incidence compared to women who wore bra less than 12 hours daily. The probable cause? pressure to the breast and surrounding areas to inhibit the flow of lymph nodes, which then causes toxins and other waste material to remain in the breasts instead of being flushed out.

Cup sizes are not created equally. For example, the cup size on a 32C is much smaller then the cup size on a 38C.

"...wearing a bra... has no medical necessity whatsoever", says Susan M. Love, M.D in her "Dr. Susan Love's Breast Book". Breasts were fine before the invention of brasserie. This is similar to the myth that women supposedly need corsets to support their stomach muscles.

70 = Percentage of women who wear the wrong bra size. Unless you believe Sadie, below.

Sadie is the queen of bras, according to the BBC - she's been in the business of fitting brassieres for twenty years. Her approach goes back to basics, "We take the lady and put her bust back where it started, and leave it there. "I can just look at somebody and know they're wearing the wrong size. I can usually tell what size they should be in," she says. "Eighty per cent of people are wearing the wrong size bra and it's because the measurement guide doesn't work. "There are thousands of bras in this land which are neither use nor ornament." Sadie starts by looking at the size of a woman's back and how their current bra sits on their shoulders. It's common to find straps digging into the shoulder area, leaving nasty ridges and grooves! Then it's a case of fitting the right bra and checking support at the front. Sadie isn't a fan of tape measures - it's more a case of a sensing the right fit and look.