October is Breast Cancer Awareness month, a time set aside to focus on a disease likely to strike one in eight American women during her lifetime. Although we know the big breast cancer risks, such as obesity and having a family history of the disease, many people aren't aware of other behaviors that seem safe, but could actually raise a woman’s risk of developing this disease. Here are the top five:

1. Alcohol

Drinking alcohol is associated with an increased breast cancer risk; the more alcohol women drink, the bigger the risk. According to the American Cancer Society, women who have two to five drinks a day increase their risk of breast cancer by about 1 and a half percent compared to women who do not drink alcohol. 

According to The Susan G Koman Foundation, an international breast cancer awareness organization, alcohol can change the way a woman’s body metabolizes estrogen, which can cause estrogen levels in her blood to rise. Past research has identified higher estrogen levels as having a major role in the development of breast cancer, although the exact reason is not completely clear.

2. Having Children Later In Life ( Or Not At All)

According to the American Cancer Society, having children after 30, or not having children at all, can increase a woman’s risk of developing breast cancer. The National Cancer Institute reports that pregnancy decreases the number of menstrual cycles a woman has in her lifetime, therefore decreasing her total cumulation of estrogen. The risk of developing breast cancer increases with the age at which women have their first child. In addition, the more children a woman has, the lower her risk for developing breast cancer.

3. Not Breastfeeding

The link between breastfeeding and breast cancer risk is little understood, but researchers suggest that breastfeeding may slightly lower breast cancer risk. According to The American Cancer Society, the longer women breastfeed, the more the risk is lowered. Once again, this increased risk seems to be related to the amount of estrogen in a woman’s body. Breastfeeding decreases the overall number of menstrual cycles she will have in a lifetime, offering similar breast cancer protection as pregnancy.

4. Birth Control

For the most part, oral birth control is safe, but some forms have been found to increase a woman’s lifetime risk of developing breast cancer. According to The American Cancer Society, Depo-Provera, an injectable form of progesterone that’s given once every 3 months as birth control, may increase breast cancer risk. However, the site reported that there is no increased risk in women 5 years after they stop getting the shots.

In addition, Studies have found that women using oral contraceptives (birth control pills) have a slightly higher risk of breast cancer than women who have never used them, but once again this risk seems to end once women stop using the pill.

5. Night Work

For many people, night work is simply an unavoidable way to earn money, but research has suggested that in women, night work may be linked to increased breast cancer risk. Once again, this risk increase seems to be hormonal. The Breast Cancer Fund report that the effect may be due to changes in levels of melatonin, a hormone that’s affected by the body’s exposure to light. The research suggests that normal high levels of melatonin at night are important for regulation of a number of natural hormones, including estrogen. This cause is still being investigated.

Read More:

Can Breast Cancer Be Detected With A Simple Blood Test? Scientists Seek New Ways To Find, Monitor The Disease: Read Here

Breast Cancer Early Symptoms 2016: Lumps And 8 Other Warning Signs: Read Here