Causes of Breast Cancer in Human

Causes of Breast Cancer

The body's cells reproduce themselves throughout your lifetime, as tissues wear out and their cells are replaced in a controlled manner. Breast cancer - like all cancers - occurs when that control is lost and cells begin to divide at an unusually high rate.

No single trigger or cause has been identified for breast cancer. Certain risk factors exist, though, that increase a woman's chance of developing it:

1. age - it's more common in women over 50
2. family history - if a woman's mother or sister had the disease before menopause, this is occasionally associated with one of two genes linked to breast cancer
3. previous breast cancer
4. family history of ovarian cancer
5. age of pregnancy - women who haven't had children, or whose first child was born after age 30
6. age of menstruation - starting periods at a young age (under 12 years old)
7. entering menopause later (over age 55) increases breast cancer risks
8. recent research suggests that women who start smoking regularly within 5 years of the onset of their menstrual periods are 70% more likely to develop breast cancer before the age of 50 than non-smokers
9. having dense breast tissue
10. radiation treatment to the chest, especially before 30 years of age
11. alcohol consumption contributes to the risk of breast cancer
12. hormone replacement therapy (HRT; estrogen plus progesterone) increases the risk of breast cancer slightly after 5 years of therapy
13. oral contraceptives increase risks slightly, if used over many years
14. obesity with excess caloric and fat intake

The increased risks of getting breast cancer associated with the above factors are often statistically quite small. In fact, for most women, the only risk factor they have is being over 50 years of age. Any concerns should be discussed with your doctor.