Weight Loss Leads to a Decrease in Breast Cancer Risk: Study

A new study recently published showed that for women who are overweight, moderate weight loss could help bring down the risk of a known cause of breast cancer.

Researchers from the Fred Hutchinson Cancer Research Center looked at 439 women who were overweight or obese and were between the ages of 50 and 75.

The results were published in the Journal of Clinical Oncology and showed that for overweight and obese women losing just five percent of their body weight contributed to lower levels of circulating estrogen, which is known to be a risk factor for breast cancer.

The women were then dived into four groups: a diet-only group, an exercise-only group, a diet and exercise group and a no-intervention group.

The results of the studied showed that the groups with the most weight loss were the diet-only and diet and exercise group with women in those groups losing an average of 10 percent of their starting weight, according to the study.

Additionally, the women in these two groups also experienced the largest drop in estrogen and other hormones linked to breast cancer.

One hormone the study examined was estrone, which is a form of estrogen. It was discovered that levels of this hormone dropped 9.6 percent in women who dieted, and 11.1 percent in women who dieted and exercised.

Another form of estrogen, estradiol, also decreased in women who lost weight. Those hormone levels dropped 16.2 percent in women who dieted and 20.3 percent in women who dieted and exercised, according to the study.

"The biggest effect was through diet plus exercise; exercise by itself didn't produce much of a change in weight or estrogen," Anne McTiernan, the study's author, said in a statement.

Scientist know that certain levels of hormones in postmenopausal women can be a risk factor for developing breast cancer and with that understanding were able to offer their conclusion.

"Our results suggest that losing just 5 percent or more of one's weight could cut by a quarter to a half the risk for the most common, estrogen-sensitive breast cancers," McTiernan said.