By Puja Gupta

New Delhi, Dec 23 (IANSlife): Obesity and overweight are manifestations of excessive and abnormal fat accumulation. There are different ways to measure obesity. Body mass index (BMI) is the most commonly used and is calculated as weight (kg) divided by height (m²). While BMI is usually associated with general obesity, waist circumference (WC) and Waist to hip ratio (WHR) have been used as measures of central or intra-abdominal obesity. The waist to Hip ratio is used as an indicator or measure of health, and the risk of developing serious health conditions.

Research shows that those who have "apple-shaped" bodies (more weight around the waist) face more health risks than compared to those with "pear-shaped" bodies (more weight around the hips). To calculate the WHR, divide the waist circumference by the hip circumference. Measurements can be recorded in either centimeters (cm) or inches (in).

Waist-hip ratio above 0.90 for males and above 0.85 for females is considered obese.

Studies have identified increased body weight as a risk factor for breast cancer. Rather than the amount of adipose tissue a woman has, its distribution, particularly abdominally, known as central obesity may be a risk factor in breast cancer development.

High insulin levels have been associated with increased risk of breast cancer and poorer survival after a breast cancer diagnosis. Waist to hip ratio (WHR) is a marker for insulin resistance and increased insulin levels in the blood (hyperinsulinemia).

Current literature suggests that obesity, lack of physical activity, alcohol consumption, and a typical high-calorie Western diet are all associated with the development of insulin resistance and hyperinsulinemia. Hyperinsulinemia may stimulate the growth of cancer cells, particularly breast and colorectal cancers. Hyperinsulinemia has also been associated with increased death rate (mortality) among breast cancer patients.

It is also been associated with both incidence of and mortality from several chronic diseases including, heart disease, hypertension, diabetes mellitus as well as cancer. In one study, data were collected on 603 patients with incidents of breast cancer, the authors tested and concluded that elevated WHR is directly related to increased breast cancer mortality. It was found to have higher risk correlation in postmenopausal women compared to premenopausal females.

Another meta-analysis involving more than 4,300 people indicated that a greater WHR is associated with increased risk of breast cancer and suggests that the avoidance of abdominal obesity may reduce risk of the breast cancer development.

Data shows that the ones who have greater waist circumference are more prone to the risk of breast cancer, especially amongst postmenopausal women who are otherwise at lower risk because of never having used estrogen replacement hormones. Study of WHR offers investigators a simple measure with which to identify people at greater risk of having or developing the "metabolic syndrome" (i.e., insulin resistance, hyperinsulinemia, hypertension, dyslipidemia and atherosclerosis), thereby to identify high-risk breast cancer patients at diagnosis.

Waist to hip ratio is potentially modifiable factor, which can be used for risk reduction. Change in lifestyle like regular exercise, maintaining a healthy body weight with normal waist to hip ratio, taking adequate rest, avoiding stress, eating a balanced diet and maintaining healthy waist to hip ratio can help in reducing the risk of development of lot of lifestyle diseases including breast cancer.