Heavy Weight During Adolescence May Increase Risk of Ovarian Cancer
A new study finds that women who are overweight during their teen years may face a higher risk of developing ovarian cancer before menopause compared to their slender peers. Weight has been a suggested risk factor for both ovarian cancer and breast cancer in several studies, though researchers still lack conclusive evidence. Interestingly, the study did not find an association between recent weight gain and ovarian cancer risk.
The National Cancer Institute estimates that approximately one out of 57 women will develop ovarian cancer during their lifetime. Ovarian cancer is the sixth most common cancer among women and the fifth leading cause of cancer deaths in women. The American Cancer Society estimates that 23,400 new cases of ovarian cancer were diagnosed in 2001, and approximately 13,900 women died from ovarian cancer last year. While ovarian cancer can be successfully treated in its early stages, the majority of cases are not diagnosed until later stages because disease symptoms can be subtle or "silent."
Researchers have identified a number of risk factors that increase ovarian cancer risk, including advancing age, family history of ovarian cancer, genetic mutations of certain genes (such as BRCA1 or BRCA2), early onset of menstruation, late menopause, and others. (Click here for a complete list of ovarian cancer risk factors). Weight has also been suggested as a risk factor for ovarian cancer, as well as for breast cancer, possibly because the body stores estrogen in fat cells.
To investigate the link between body weight and ovarian cancer risk, Dr. Kathleen M. Fairfield of Harvard Medical School and colleagues studied the current weight, weight at age 18, and adult weight change of 109,445 adult female nurses, 402 of whom had developed ovarian cancer. The researchers used body mass index (BMI) to determine whether the women were normal weight, overweight, or obese. BMI measures a persons total body fat based on weight and height; it is derived by multiplying a person's weight in pounds by 703 and then dividing it twice by the persons height in inches. According to federal guidelines:
(Click here to view a chart that shows BMI by height and weight).
Dr. Fairfield and her colleagues found that women who were heaviest at age 18 (with a BMI of 25 or higher) faced the greatest risk of developing ovarian cancer before they reached menopause. However, there was no association between adolescent weight the ovarian cancer risk after menopause, when the majority of cases occur.
The researchers were alarmed by the findings because obesity has increased significantly in younger American women in the recent past. Though further studies are needed to better understand the relationship of body weight and ovarian cancer risk, weight is one factor women can control. Weight has also been associated with a higher risk of heart disease and other health problems.