There is no simple answer to the question about breast cancer causes, because it is really not very clear exactly what causes breast cancer though certain factors can in fact be considered breast cancer causes.
There are certain risk factors that increase one’s chances of developing breast cancer:
Gender and Age: Women are literally a hundred times more likely to have breast cancer as compared to men. For every man who develops breast cancer, a hundred women do so.
And the risk of getting breast cancer increases with a woman’s age. Statistics show that two out of three women who have invasive breast cancer are 55 years of age or older by the time the cancer is detected.
Genetic factors or Predisposition: As many 10% of breast cancers are linked to genetic factors; such as mutations in certain genes. There is also family history that affects a woman’s chances of getting breast cancer.
If a woman has close female relatives who have had breast cancer, her chances of getting breast cancer are significantly higher; the risk is said to double in this case according to certain experts.
Previous Cancer: Here we are talking not about the reemergence of a previous cancer but the development of a new cancer in the same or another breast.
Hormonal factors: Women who have had the longest exposure to the female hormones; in particular estrogen, are more likely to develop breast cancer.
So breast cancer causes include higher exposure to female hormones, such as those who started to menstruate early (before age 12) and those that have a late menopause are more at risk.
Also women who have used the birth control pill over long periods of time have had more hormone exposure and consequently are more at risk.
Women who have had no pregnancies, or have had late pregnancies are also more at risk. Women who have undergone hormone replacement therapy (HRT) for a considerable duration are also more at risk.
Fitness levels: Exercise would appear to lower risk of breast since exercise has been seen to reduce estrogen production and can affect ovulation and hence lack of exercise could indirectly be said to be a cause of breast cancer.
High body fat could also be termed as a cause for breast cancer since it is not only the ovaries but also body fat that produces the estrogen hormone.
Lifestyles related factors: There are several lifestyle related factors that could be said to be breast cancer causes. Smoking increases risk of developing a number of different cancers including breast cancer.
Smoking also reduces the kinds of cancer therapies that are available for treatment. For instance reconstructive surgery may not be possible. Women with certain high fat diets also increase their risk of getting breast cancer.
Alcohol use is also thought to increase one’s chances of getting breast cancer, because having more than two drinks a day has been seen to increase the proportion of estrogen in the blood stream. Certain occupations that increase exposure to radiation and certain environment pollutants also increase risk.