While obesity has been shown to increase breast cancer risk in elderly for younger women the opposite seems to be true. For pre-menopausal women a higher body fat was linked to lower breast cancer risk according to researchers. The study published in the journal JAMA Oncology showed that there was 23 per cent lower breast cancer risk linked to each five-unit increase in body mass index (BMI) between the ages of 18 and 24. At ages 25 to 34 each five-unit increase in BMI was linked to 15 per cent lower risk. There was a 13 per cent lower risk