Studies done in the recent past have demonstrated that obesity in women, especially around the waist is related to development of breast cancer. We know that hormone receptor positive cancer cells in breast cancer depend upon estrogen for their growth.
Obesity in Women is Related to Development of Breast CancerBody mass index (BMI) is the square of the ratio of the weight in kilograms to height in meters. BMI is believed to be a better indicator of a person’s health than weight alone. When the BMI is higher than 25 kg/m2 but less than 30 kg/m2, the person is said to be overweight. A BMI of more than 30 kg/m2 is defined as obesity.
Many studies done in the recent past have demonstrated that obesity in women, especially around the waist is related to development of breast cancer. We know that hormone receptor positive cancer cells in breast cancer depend upon estrogen for their growth and multiplication. After menopause, fat becomes the primary source of estrogen in females. Therefore, higher the amount of fat deposition in a post menopausal female, the more is the likelihood of development or recurrence of breast cancer. Xenestrogens may also be playing a part in the development of breast cancer. They are toxic compounds structurally similar to estrogen formed as a result of environmental pollution. These xenestrogens are stored in the fat cells of obese women and act in a manner similar to estrogens. However they are capable of producing mutations in the normal breast cells, leading to the development of breast cancer.
Another study implicates the levels of hormones leptin and adiponectin in development of breast cancer. As a female gains weight, the level of leptin increases with a corresponding decrease in the levels of adiponectin. This reversal in the normal ratio of the two hormones may also prompt carcinogenic changes.
Statistics Tie Obesity to Increased Post Menopausal Breast Cancer RiskThere are considerable statistics which tie obesity in women to increased post menopausal breast cancer risk. Level of estrogen is 50 to 100 % higher in obese women as compared to women with a normal BMI. Continuous exposure of estrogen sensitive areas to more estrogen leads to the growth of estrogen receptor positive breast cancer. Moreover, there are three times more chances of a late diagnosis of breast cancer in heavy women as it is difficult to detect the tumor in them. Post menopausal women are 1.5 times at more risk to develop breast cancer as compared to normal healthy women. If women could maintain a healthy BMI of less than 25 throughout their lives, about 11,000 to 18,000 women of above 50 years could be saved from mortality resulting due to breast cancer. Thus, we find a strong statistical association between obesity and risk of developing post menopausal breast cancer.
A balanced diet and regular exercising is essential to maintain a healthy BMI throughout the life and the reduced risk of developing breast cancer at a later stage is an added benefit to do so. Some form of exercise, like walking for 30 minutes everyday, reduces the risk of breast cancer in post menopausal women by at least 20 % provided they are not obese. An increase in BMI by 5kg/m2 between the ages of 20 and 55 to 74 (post menopausal age) doubles the risk of developing post menopausal breast cancer as compared to women who maintain their BMI at less than 25 kg/m2. Taking into consideration these above mentioned statistics which tie obesity to increased risk of developing breast cancer, it is better to keep in shape than to repent later.