Research published recently in the Journal of National Cancer Institute suggests a new form of cancer prevention: losing weight and keeping it off. This study was specifically attuned to women who lost weight over the age of 50 and were successful in maintaining weight loss, as well as to women not using postmenopausal hormones.
This study offers hope for the thousands of women who are diagnosed with breast cancer every year. Although improved treatment options have increased the survival rate for breast cancer, with only 1 in 38 women dying from the disease, the American Cancer Society still estimates that 268,600 women will receive a diagnosis of invasive breast cancer in 2019 alone and a further 62,930 people will receive a diagnosis of noninvasive cancer.
Previous studies have shown that high body mass index is a risk factor for postmenopausal breast cancer, however, until now scientists and medical professionals have not been clear on the impact that losing weight can have on a woman’s risk for developing breast cancer.
This most recent study analyzed data from the Pooling Project of Prospective Studies of Diet and Cancer (DCPP) to look at over 180,000 women aged 50 and older from ten studies – one of the largest data sets to consider weight loss as a specific breast cancer factor. Conducted by researchers at the American Cancer Society and Harvard T.H. Chan School of Public Health, the study monitored the weight of the participants over 10 years (at study enrollment; after about five years; then again about four years later) to determine the potential link between sustained weight loss and risk of breast cancer.
They found that compared to women who maintained a stable weight, women who lost weight and kept it off showed a reduced risk of breast cancer. And to make the case even stronger for that New Year’s gym membership, the more weight loss, the lower the risk became. According to Science Daily, “Women who lost 2 to 4.5 kg (about 4.4 to 10 lbs.) had a 13% lower risk than women with stable weight. Women who lost 4.5 to 9 kg (10- 20 lbs.) had a 16% lower risk. Women who lost 9 kg or more (20+ lbs.) had a 26% lower risk.”
"Our results suggest that even a modest amount of sustained weight loss is associated with lower breast cancer risk for women over 50," said lead author Lauren Teras, PhD. "These findings may be a strong motivator for the two-thirds of American women who are overweight to lose some of that weight. Even if you gain weight after age 50, it is not too late to lower your risk of breast cancer."