Breast Cancer Risk and Causes

Breast Cancer Risks and Causes

Whatever increases the risk of getting a disease is called a Risk Factor. Having one or more of the following risk factors does NOT necessarily mean that you will definitely get cancer. Many people who have these risk factors never get it and some people with no risk factors at all develop it.

Lifestyle Risk Factors

Certain breast cancer risk factors are related to personal behaviors, such as diet and exercise. Other lifestyle-related risk factors include decisions about having children and taking birth control.


Drinking alcohol has been linked to an increased risk of developing breast cancer by a small amount. The risk increases with every unit of alcohol consumed per day. Women who have 1 alcoholic drink daily have a very small increase in risk, those who have 2 to 5 drinks daily have about 1½ times the risk of women who don’t drink alcohol. Women are advised to have 1 alcoholic drink a day. A drink is 12 ounces of regular beer, 5 ounces of wine, or 1.5 ounces of 80-proof distilled spirits.

Being overweight or obese

Women who are overweight after menopause have a higher risk of developing breast cancer. The ovaries make most of the estrogen before menopause and the fat tissue makes only a small amount. When the ovaries stop making estrogen after menopause, the fat tissue takes over. Having a lot fat tissue after menopause can increase the level of estrogen, thus increasing the chance of developing breast cancer. Likewise, women who are overweight or obese tend to have higher blood insulin levels. Higher insulin levels have been linked to some cancers, including breast cancer. Women are advised to maintain a healthy weight throughout their lifetime by balancing their food intake with adequate physical activity.

Having children

Women who have not had children or who had their first child after age 30 have a slightly higher breast cancer risk overall. Having many pregnancies and becoming pregnant at an early age reduces breast cancer risk overall.

Family History and Genes

A very strong family history of breast cancer might indicate that there is a faulty gene in the family. There are several gene faults that can increase breast cancer risk. Some people have a higher risk of developing breast cancer than others because members of their family have had particular cancers. This is called a family history of cancer.

Having a mother, sister or daughter diagnosed with breast cancer approximately doubles the risk of breast cancer. This risk is higher when more close relatives have breast cancer, or if they are under 50. But more than 8 out of 10 women who have a close relative with breast cancer will never develop it.

Physical Activity

Physical activities like exercise have proven to reduce the risk of developing breast cancer. A study from the women’s health initiative discovered that 1 to 3hours of exercise per week of a quick walk reduced a woman’s risk of breast cancer by 18%. Activities that improve strength and flexibility, such as weight lifting, stretching, or yoga, are also beneficial to reducing the risk of breast cancer.

There is no sure way to prevent breast cancer. But you can lower the risks by managing risk factors that are under your control.