Young girls with a large body size may have a decreased risk of postmenopausal breast cancer compared with thinner girls, according to a study published in Breast Cancer Research.
Body weight is a factor that appears to influence not only the risk of developing several types of cancer but also cancer survival. In general, healthy-weight individuals have a lower cancer risk and better cancer outcomes than individuals who are overweight or obese. For some cancers, however, the relationship between body size and cancer risk varies over the course of the lifespan. In the case of breast cancer, higher body weight reduces the risk of breast cancer in premenopausal women but increases the risk in postmenopausal women.
To explore the relationship between childhood body size and risk of postmenopausal breast cancer, researchers in Sweden assessed almost 3,000 women who had been diagnosed with breast cancer and compared them with 3,000 who had not been diagnosed. Body size at age seven was measured for both groups.
- Even after accounting for factors such as age at first menstrual period, adult body mass index, and breast density, a large body size at age seven was linked with a 27% reduction in risk of postmenopausal breast cancer. The protective effect of a larger body size at age seven was observed regardless of estrogen-receptor and progesterone-receptor status but was stronger for estrogen receptor-negative cancers than for estrogen receptor-positive cancers.
The researchers concluded that women who had a larger body size at age seven may have a decreased risk of developing postmenopausal breast cancer. These findings may be a useful contribution in estimating a womanâ€™s breast cancer risk, as information on childhood body size is relatively easy to collect with old photographs.
Reference: Li J, Humphreys K, Eriksson L, et al. Effects of childhood body size on breast cancer tumour characteristics. Breast Cancer Research. 2010;12:R23doi:10.1186/bcr2564.