Like Type 2 diabetes, Gestational diabetes or pregnancy-induced diabetes raises the risk of developing breast cancer, especially one type. That is what researchers at the National Institutes of Health in North Carolina, United States, concluded in their article published in February 2017 in the British Journal of Cancer.

Their study included 50,884 women from 35 to 74 years of age. They were followed from 2003 to 2009. Women with a history of Gestational diabetes were 73 percent more likely to have a type of cancer of the breast called estrogen-negative (ER-) than women without a history of diabetes during their pregnancy. Participants who had experienced two or more cases of Gestational diabetes had an 81 percent higher risk of developing any of the types of breast cancer than those who had not had the condition. The investigators suggest women who have had Gestational diabetes, and especially those with more than one case, should be concerned about the risk even more than women without a history of Gestational diabetes.

According to the Mayo Clinic in the United States, there are several other good ways to prevent developing cancer of the breast. By …

  • limiting the intake of alcohol,
  • avoiding smoking,
  • keeping your body weight within a healthy range,
  • taking part in a regular physical activity,
  • breastfeeding,
  • avoiding radiation and pollution, and
  • taking the smallest amount as possible of hormone therapy.

The Centers for Disease Control and Prevention (CDC) in Atlanta, United States, recommends not more than one alcoholic drink per day for women. One drink a day is not an average number but a moderate amount for each day.

Tobacco smoke contains three chemicals linked with cancer. According to the Breast Cancer Fund, both active and passive smoking have been linked to this form of cancer.

According to the National Institutes of Health in the United States, physical activity can help reduce the risk. This is especially true after menopause.

In societies in which women traditionally breastfeeding with only one breast; the breast not used to feed the infant has a higher risk of developing cancer. Women who breastfeed for at least one year reduce their risk and those who breastfeed two years or more have an even lower risk of developing breastfeeding cancer.

Radiation can cause changes, or mutations, in the DNA. Damaged DNA can lead to damaged cells and cancer. Some scientists think traffic air pollution raises the risk of breast cancer.

Estrogen, a female hormone used to treat menopause, can encourage the growth of some types of breast cancer.