A person is considered overweight when his/her BMI ( Body Mass Index) is more than 25 and considered obese when the BMI is more than 30. With increase in weight, women have an increased chance of getting breast cancer, increase their chances of recurrence and wound infection following surgery. This is true especially in women who have undergone menopause as the body gets the hormone estrogen from the fat. With more fat, there is more estrogen and more chances of developing breast cancer. With reduction in weight, the chances of breast cancer reduces. Hence a healthy lifestyle is encouraged.
Studies have shown that moderate exercise for 4 to 7 hours a week reduces the risk of breast cancer. For those women affected with breast cancer walking 3 to 5 hours a week at an average pace increases their chance of surviving their disease. Exercising reduces the fat content in the body and controls the hormones which regulate how breast cells grow and behave. Women who do not exercise are encouraged to start slowly and exercise daily.
Drinking alcohol increases breast cancer by about 20% more than those who do not drink. It can increase the levels of estrogen and other hormones responsible for breast cancer. It can also damage the DNA in cells producing cancer.
Smoking gives rise to many diseases in the body of which breast cancer is also one. It produces breast cancer in a younger age group, poor wound healing, failure in breast reconstruction and reduces the survival of those who smoke. Inhaling the smoke from others smoking has also found to produce breast cancers.
Radiation is often given to the chest to treat other tumours such a lymphoma at an early age before they are 40. The chance of breast cancer increases at an earlier age and is highest when radiation is given at adolescence when the breasts are developing. The chances of developing breast cancer can be as high as 22 to 40 times when compared to a normal person. Hence they need to be followed up frequently by mammograms/MRI. After completing their families, they can also go for prophylactic mastectomies ( Removal of breasts as a precaution before the onset of cancer) and reconstruction. This will reduce the rate of breast cancer by more than 95%. To know more about Breast Reconstruction. Please click here
Breast cancer is most common in women between 40 to 60 years. However, compared to 25 years back we see a lot of women having breast cancers at an earlier age group. It is not uncommon to see women with breast cancers in their twenties and thirties. This is shown in the figure below, which depicts the percentage of breast cancers in each age group both today and 25 years back. This is probably due to our change in lifestyle and increasing westernisation.
As breast cancer is increasing and is seen more in the younger age groups, it is widely felt that a change in the diet could be one of the reasons behind the change. Although no particular food is found to be a causative factor, it is found that breast cancer is less common in countries where the typical diet is plant-based and less in total fat content (Polyunsaturated fat and Unsaturated fat). Some feel that people who eat a diet rich in fat may have a high risk of developing breast cancer in later life even though they don’t become overweight.
If a woman is diagnosed with breast cancer earlier, she is 3 to 4 times more prone compared to another woman in developing another cancer in the opposite breast and also in the same breast if she had undergone a lumpectomy earlier. Hence it is important that woman keep following up frequently which includes a
Women who have their first pregnancy beyond the age of 30 are more likely to develop breast cancer compared to women who develop breast cancer before the age of 30 years. When women are in their teens, the cells in the breast are immature and very active until their first pregnancy. During their first pregnancy, the cells become mature under the influence of various hormones. Being pregnant also reduces the number of menstrual cycles which also contributes to reducing the risk of breast cancer. Having a first child before the age of 30 years reduces the risk of breast cancer.
Breast feeding beyond one year helps to protect women from breast cancer. Breastfeeding less than a year has less benefit. The reasons why breastfeeding protects breast health are
Women who have more menstrual cycles (periods) in their life have a higher chance to develop breast cancer than those who have lesser menstrual cycles. Thus women who start having menstruation earlier than 12 years, who develop menopause later than 55 years and who do not have any children are more prone to develop breast cancer. Of late it is found that girls have their onset of puberty and development of breasts at an earlier age due to various changes in lifestyle which increases the chances of estrogen influence to the breast and breast cancer.
Hormone replacement tablets are taken to reduce the symptoms of menopause like hot flashes, change in mood and to prevent osteoporosis. However, it is found that they can increase the chance of breast cancer.
Combination hormone replacement therapy includes the hormones estrogen and progesterone. It is found that within the first two years the risk of getting breast cancer and detecting it only in an advanced stage increases. The risk normalises within first two years of stopping the hormone replacement therapy.
Estrogen-only Hormone therapy increases the chance of breast cancer only when it is used for more than ten years. This therapy also increases the chance of ovarian cancers.
Women who take hormone containing oral contraceptives have a small increase in chance compared to that of the general population. The increase was about one new breast cancer case per 7,690 women who used hormonal contraceptives for a year. Women who take it for a longer time have an increase in chance compared to those who take for a shorter time.