Excess Fat Around The Waist May Increase Death Risk For Women
Women who carry excess fat around their waists were at greater risk of dying early from cancer or heart disease than women with smaller waistlines, even if they were of normal weight, report researchers from Harvard and the National Institutes of Health.
There is increasing evidence that excess abdominal fat is a risk factor for long-term conditions like diabetes and heart disease. However, the relationship between abdominal obesity and risk of death has not been widely studied. The current study is one of the largest, most comprehensive investigations of abdominal obesity and women's risk of premature death.
Researchers followed more than 44,000 women over the course of 16 years to track their medical history and lifestyle. The majority of the women who took part in the study were white, thus the researchers do not know if their findings pertain to other groups of women or to men.
All the women included in the study were registered nurses. At the beginning of the study the women were asked to measure their waists and hips. Every two years, the women completed questionnaires about their health, providing information about their age, activity level, smoking status, diet, blood pressure and cholesterol levels.
The researchers examined the cause of death for all women who died over the course of the study. In total, 3,507 deaths occurred -- of these, 1,748 were due to cancer and 751 were due to heart disease.
The researchers discovered that women with greater waist circumferences were more likely to die prematurely, particularly from heart disease, when compared to women with smaller waists. For example, women with waist size equal to or greater than 35 inches were approximately twice as likely to die of heart disease as were women with a waist size less than 28 inches, regardless of their body mass index. Similarly, women with a waist size equal to or greater than 35 inches also were twice as likely to die of cancer as were women with a waist size less than 28 inches.
Women who had a greater waist circumference and were also obese were at the greatest risk of premature death. Researchers determined if a woman was overweight by calculating her body mass index (BMI), a measure of a person's weight in relation to height. BMI is used to estimate the proportion of a person's weight that derives from body fat. A BMI between 18.5 and 24.9 is considered healthy. A BMI of 30.0 - 39.9 is regarded as overweight.
Greater waist circumference is a sign of collecting excess fat around one's midsection, called abdominal obesity. According to the "Clinical Guidelines on the Identification, Evaluation and Treatment of Overweight and Obesity in Adults" published by NHLBI in cooperation with NIDDK, a healthy waist limit for women is 35 inches and, for men, 40 inches. Waist circumference is determined by measuring around the waist at the navel line.
This study confirms the importance of maintaining a healthy weight to prevent chronic diseases and premature death. It also shows that maintaining a healthy waist size is an important goal.