Drinking just three cups of coffee a day may make women's breasts shrink, a study finds.

Nearly 300 women were surveyed by researchers from Sweden's Lund University about their bust measurements and how many cups of coffee they drank in an average day.

They found that three cups a day was enough to start making breasts shrink, with the effects increasing for every additional cup of coffee consumed.

They said there was a clear link between drinking coffee and smaller breasts, as about half of women possessed a gene shown to link breast size to coffee intake. The news wasn't all bad, however. Researchers also found that regular caffeine intake may reduce the risk of breast cancer.

"Drinking coffee can have a major effect on breast size," said Helena Jernstroem, a lecturer in experimental oncology at Lund University. "Coffee-drinking women do not have to worry their breasts will shrink to nothing overnight. They will get smaller, but the breasts aren't just going to disappear."

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