Duration of Obesity Increases Cancer Risk in Adult Women

The duration of high body mass index (BMI) in the adult lives of females was found to be associated with the risk of cancer.

Most studies have explored this relationship by looking at cross-sectional information on overweight and obese individuals. However, in a study published in PLOS Medicine, researchers used multiple BMI measurements over time from approximately 74,000 women to examine the association between the duration of being overweight and obese with the risk of cancer.

During the 12.6-year mean follow-up, more than 6000 women were diagnosed with cancer. Researchers also took into account additional factors related to obesity, such as physical activity, diabetes, hormone use, smoking, and diet.

The results of the study showed that every 10-year increase in adulthood overweight duration was associated with a 7% increase in the risk of all obesity-related cancers (95% CI: 6-9%). Furthermore, there was also a 5% (3-7%) increase in the risk of developing postmenopausal breast cancer, and 17% (12-22%) increase in the risk of endometrial cancer.

Once researchers adjusted for the intensity of being overweight, the figure increased to 8% (5-12%) for postmenopausal breast cancer, and 37% (29-46%) for endometrial cancer. Some limitations to the study include BMI not being an ideal measure for body fat, and the cohort being dominated by non-Hispanic white women.

Although there are limits, the study’s large scale and longitudinal BMI data helped provide compelling evidence that overweight duration is an important risk factor for cancer, according to the study.

“[I]f this is true, health care teams should recognize the potential of obesity management in cancer prevention and that excess body weight in women is important to manage regardless of the age of the patient,” the study authors wrote.