NEW YORK (Reuters Health) - Weight loss in older women may reduce the risk of having a serious type of breast cancer, compared with those who maintain the same weight and weight gain, a US study suggests.
While obesity has long been associated with an increased risk of breast cancer, previous research has presented a distorted picture of how weight loss can reduce that risk.
For the current study, researchers calculated the body mass index of more than 61,000 women twice, three years apart, and then continued for more than 11 years, during which more than three thousand were infected with breast cancer.
Compared with women whose weight was stable during the first three years of study, those who lost at least five percent of their weight during those three years over the next decade were 12 percent less likely to die.
"Our findings suggest that women can reduce their risk of cancer, even if they are obese after losing some weight," said Rowan Chlabowski of the City of Hope Medical Center in Duarte, California, the lead author of the study. "It should be encouraging for women as it is possible for many to achieve and maintain a modest weight reduction."
All the women in the study have reached menopause, which is less than the production of estrogen and the main source of this hormone is fat tissue, so obesity increases the risk of cancer, because this hormone helps tumors grow.
