medwireNews: Postmenopausal women who lose weight have a lower risk for breast cancer than those who maintain a stable weight, report researchers.
Of 61,335 participants (aged 50–79 years) of the Women’s Health Initiative Observational Study, 13% lost weight (≥5%) from baseline to year 3, 67% maintained a stable weight, and the remaining 20% gained weight (≥5%).
A total of 3061 cases of incident invasive breast cancer occurred over an average follow-up of 11.4 years from the year 3 visit, with the risk significantly reduced for women with weight loss versus those with stable weight after adjustment for a raft of factors (hazard ratio=0.88).
Rowan Chlebowski (City of Hope National Medical Center, Duarte, California, USA) and co-authors point out that the association between weight loss and reduced risk remained regardless of whether the loss was intentional or otherwise.
And the findings did not change appreciably either when breast cancers diagnosed during the first year of follow-up were excluded or mammography frequency was taken into account.
Of note, weight gain did not appear to confer a higher breast cancer risk.
The investigators highlight that previous research has shown a link between the substantial weight loss resulting from bariatric surgery and reduced breast cancer risk. “Our current findings suggest benefit for smaller degrees of weight loss achievable without surgery,” they conclude in Cancer.
medwireNews is an independent medical news service provided by Springer Healthcare. © 2018 Springer Healthcare part of the Springer Nature group