October is Breast Cancer Awareness Month. During this month, we honor and support those who have survived and those we have lost. Scientists have found that cancer grows when a cell’s DNA becomes damaged, but the reason and cause for this damage are still unknown, though it’s likely that it’s a combination of both genetic and environmental factors. Most patients will never know the exact cause of their cancer, but there are established risk factors associated with breast cancer: some avoidable, some unavoidable. These are eight of the known risk factors of breast cancer.

1. Being Female

Breast cancer is 100 times more common in women than men and statistics from the American Cancer Society suggest that about 440 men die from breast cancer each year compared to 40,000 women. A man’s risk of developing breast cancer is about 1% and these rates have remained stable over the past 30 years. Meanwhile, about 1 in 8 US women will develop breast cancer over the course of her lifetime. After skin cancer, breast cancer is the most common form of cancer diagnosed in women.

2.Menopause & Menstrual Cycles

Women who have had more menstrual cycles because they either started their period early or went through menopause late have a higher risk of breast cancer. This is due to longer lifetime exposure to estrogen and progesterone.

3. Increasing Age

The older you are the higher your risk. In fact, most women who get breast cancer (about 80%) are over the age of 50 while most men who develop breast cancer are over the age of 60 respectively. This increased risk is due to the fact that as we age, there are more opportunities for genetic damage and our bodies become less capable of repairing genetic damage.

4. Personal History

If you have been diagnosed with breast cancer before, you are three to four times more likely to develop new cancer in the other breast or in a different part of the same breast. To quell this, you might take medicine to reduce your risk like selective estrogen receptor modulators or aromatase inhibitors.

5.Obesity

A study found that women who gained 20 pounds after age 18 had a 15% higher risk of breast cancer than women who gained little to no weight. Similarly, women who gained at least 55 pounds, had a 45% higher risk. This increased risk can be attributed to the fact that overweight or obese women experience higher estrogen and insulin levels and these increased levels are a trend in those who are diagnosed with breast cancer post-menopause.

6. Radiation Exposure

Radiation treatments to your chest can increase your risk of breast cancer by a significant amount. If this occurs while the breast are still developing throughout adolescence or young adulthood, there is an even higher risk of breast cancer. With that said, radiation treatment in older women (after age 40 to 45 doesn’t seem to increase the risk of breast cancer.

7. Drinking Alcohol

Alcohol can increase the risk of breast cancer. In a comparative study of women who drank three drinks per week and women who don’t drink at all, women who have three alcoholic beverages or more have a 15% higher risk of breast cancer. Each additional drink after that increases the risk of breast cancer another 10%.

8. Family History

Having a family history of breast cancer means having close relatives who have been diagnosed with the disease. In many cases, these women who have sisters, mothers, aunts, daughters, or grandmothers that have been diagnosed have a higher risk of developing breast cancer themselves. Often times, this is because this family history is linked to an abnormal gene associated with breast cancer called BRCA1, BRCA2, or CHEK2.

Keep in mind that though these are risk factors, these are not the guaranteed cause of breast cancer. Having one of several of these risk factors doe not necessarily mean that you will develop breast cancer. Similarly, many women who develop breast cancer exhibit none of these symptoms other than being a woman. In fact, 60% to 70% of breast cancer patients do not have a connection to the known risk factors. These controllable factors should be controlled even still, alcohol consumption should be limited, sedentary habits should be switched with more active ones. It’s important to know the risk factors so that you can find ways to eliminate this risk to the best of your ability!