By Amy Goodrich

Adopting a healthy lifestyle can significantly slash the risk of developing breast cancer in women who carry common gene variants linked to breast cancer, a new study published in JAMA Oncology suggests. The discovery marks a significant shift in the cancer conversations and prevention strategies to help women reduce their odds of developing breast cancer.

The findings offer hope for women that have a high genetic risk and a family history of breast cancer. Senior lead researcher Nilanjan Chatterjee, a professor at Johns Hopkins Bloomberg School of Public Health in Baltimore, hopes that the study will help women realise that although they have a higher risk, it does not guarantee they will develop breast cancer through the course of their life.

“People think that their genetic risk for developing cancer is set in stone,” said Nilanjan Chatterjee in a news release from Johns Hopkins Bloomberg School of Public Health “While you can’t change your genes, this study tells us even people who are at high genetic risk can change their health outlook by making better lifestyle choices such as eating right, exercising and quitting smoking.”

Key lifestyle factors

According to the authors of the study, breast cancer remains the most common form of cancer diagnosed in women in developed countries of the Western world. In 2014, an estimated 232,670 new cases were diagnosed and roughly 40,000 women died in the United States alone.

More than 17,000 women with breast cancer and nearly 20,000 women without the disease were tested for 24 gene variants previously linked to an increased breast cancer risk. Furthermore, they estimated the effect of 68 other gene variations that the participants were not tested for.

Using this genetic information along with other unchangeable factors – such as family history and the age menstruation started – and lifestyle habits, Nilanjan Chatterjee and his colleagues developed a model to predict the risk of breast cancer.

They found that the average 30-year-old Caucasian woman has an 11 percent chance of developing breast cancer by age 80. Women who had a high risk based on family history and genetic risk factors could lower their chances of developing the disease over their lifetime by maintaining a healthy weight, not smoking and drinking, and not using hormone therapy.

“Everyone should be doing the right things to stay healthy but motivating people is often hard,” Chatterjee said. “These findings may be able to help people better understand the benefits of a healthy lifestyle at a more individualised level,” he added.

Get physical

Nilanjan Chatterjee and his team are not the only ones that, recently, linked a healthy lifestyle to reducing the odds of developing breast cancer. A team led by Steven Moore, a cancer epidemiologist at the National Cancer Institute, pooled the data from 1. 4 million health care professionals who reported on their physical activity levels over an average period of 11 years.

His team suggests in their report, published by the journal JAMA Internal Medicine, that higher levels of leisure-time activity may boost protection against a wide range of cancers, breast cancer included. They claim that people who never smoked or stopped smoking, stayed fit, managed their weight, and had no more than a drink or two a day, could reduce the risk of dying from cancer by half.

“Everybody knows physical activity reduces heart disease risk,” says Moore. “The takeaway message here is that physical activity might reduce the risk of cancers as well. Cancer is a very feared disease, but if people understand that physical activity can influence their risk for cancer, then that might provide yet one more motivating factor to become active.”