A new study reveals that nearly 40 percent of hormone receptor-positive postmenopausal breast cancers may be linked to excess body fat. Thus, the risks associated with obesity are significantly underestimated.
Body fat, a risk for breast cancer – Photo Shutterstock
A Spanish study published in the Journal of Epidemiology & Community Health suggests that nearly 40% of postmenopausal breast cancers that are positive for hormone receptors may be associated with excess body fat. This proportion is considerably higher than current estimates, which indicate that only one in ten such cases is linked to obesity, as commonly measured by body mass index (BMI). The researchers point out that, for this reason, the real impact of obesity on the risk of breast cancer was probably underestimated, according to News.ro.
Body mass index (BMI) is not a very accurate measure of body fat, especially in older women, because it does not take into account factors such as age, gender or ethnicity, the researchers point out.
How the study was conducted
Researchers compared body mass index (BMI) with CUN-BAE (Body Adiposity Estimator) in 1,033 postmenopausal white women with breast cancer and 1,143 healthy women, adjusted for age, sex, and geographic region. The Spanish multi-control study (MCC) assessed environmental and genetic factors associated with different types of cancer, including breast, stomach and prostate, as well as chronic lymphocytic leukemia, among people aged 20 to 85 years.
All participants were questioned about risk factors, including sociodemographic data, lifestyle, and medical and reproductive history. Diet information was obtained by a semi-structured, validated questionnaire that included 140 food frequency questions, and usual alcohol consumption between 30 and 40 years was assessed by a self-administered questionnaire.
The study compared body fat classification using CUN-BAE (body fat) and BMI in postmenopausal women with and without breast cancer. CUN-BAE divides fat into four categories (
The researchers point out that due to the nature of the case-control study, they were unable to establish causal factors. They also acknowledge that the CUN-BAE formula was derived from a sample of sedentary individuals and that the number of non-hormone-positive breast cancer cases was limited.
Excess fat, a risk factor
However, the researchers conclude that “study results indicate that excess body fat is a significant risk factor for hormone receptor-positive breast cancer in postmenopausal women“.
“Findings suggest that population impact may be underestimated when using traditional BMI estimates and that more accurate measures of body fat, such as CUN-BAE, should be considered when estimating cancer burden attributable to obesity in postmenopausal breast cancer“, the authors also specified in a press release, emphasizing that this is crucial for planning effective prevention initiatives.
In 2020, Romania reported 12,085 new cases of breast cancer, and 3,918 deaths from breast cancer, according to the International Agency for Research on Cancer.
