According to one analysis, being overweight does not negatively impact your risk for breast cancer if you are pre-menopausal.
For a long time, we have heard that body fat or BMI directly correlates with a woman’s risk of breast cancer coming back. In fact – it is touted as one of the most important factors within a woman’s control to help prevent recurrence.
BUT…hot off the presses…
In the largest of its kind, pooled analysis of nearly ¾ of a million pre-menopausal women, there appears to be an INVERSE or OPPOSITE relationship to body mass and the likelihood of developing breast cancer. The inverse association of body mass and breast cancer risk was evident in all pre-menopausal women, but was most strongly present in women with hormone-receptor positive (HR+) breast cancer. In other words, for pre-menopausal women whose body mass was above average, the risk of developing breast cancer was lower than for women of the same age who were considered underweight. Most notable was the 4-fold difference in the 18-24 age group.
The analysis was conducted by The Pre-menopausal Beast Cancer Collaborative Group and looked at women divided into four age groups, 18-24, 25-34, 35-44, and 45-54. Other criteria including tumor type and sub-type and hormone receptor status were assessed for impact in this analysis.
SO – what do you do with this information? Nothing, really; except, don’t beat yourself up about your weight when you were in your early 20s. Turns out – a little bit of extra weight at that time of your life may have been protective. And this is what is really intriguing to researchers. Now that they have uncovered this surprising inverse association, their next step is to try to understand the biological mechanisms that create the association – The WHY and to see if there is any lesson to be learned for disease prevention.
Stay tuned for future research results.
- Jama Oncol. Doi: 10.1001/jamaoncol.2018.1771
Published online June 21, 2018