A new study reveals that women who are overweight or obese are at higher risk of getting cancer with time.
The new study was conducted on postmenopausal women. It was published in the journal PLOS Medicine. The results of the longitudinal study revealed that a high body mass index in women was associated with higher risk of developing several kinds of cancer such as breast and endometrial.
The study holds weight because it is the first one to explore the relationship present between cancer risk and duration of being overweight in women. The lead author of the study, Melina Arnold, a scientist at the World Health Organization’s International Agency for Research on Cancer, said that “Given the result from previous studies supporting the overall link between obesity and cancer, our results are in line with what we know about this relationship. Yet it adds to current scientific evidence by suggesting that there seems to be a cumulative effect of obesity on cancer risk.”
The findings of the study are simple. As the weight and the duration of being overweight goes up so does the risk of cancer.
The researchers of the study analyzed data of 73,913 women from across the U.S. The information from the long-term national health study Women’s Health Initiative was used. The researchers looked at the BMI measurements of women along with their diet, physical activity, hormone use, smoking, and their history of diabetes and cancer.
According to the Centers for Disease Control and Prevention, BMI has been used as a screening tool for being obese and overweight. A BMI measurement of 25-30 falls in the range of being overweight while a measurement of 30 and higher falls in the range of being obese. All of the data that was used in the study spanned 12 years. The analysis of the data diagnosed 6,301 women with obesity related cancers.
The researchers made a discovery that for every 10 years women remained overweight during adulthood their risk for all cancers (obesity-related) increased by as much as 7%. Postmenopausal breast cancer risk went up by 5% while an increase of 17% was seen in the risk of endometrial cancer.
Dr. Melina Arnold said that “This is biologically plausible, as earlier and longer periods of overweight and obesity have been found to increase the risk and severity of hypertension, insulin resistance, chronic inflammation, DNA damage and changes in hormone metabolism, which are all key mechanisms increasing also the risk of cancer.” She went on to say that research is needed to see if the same findings are true for women who lose weight for a period of time and gained it back. We also showed in our study that the risk to develop these cancers is not only dependent on overweight duration itself but also on the degree of overweight over time. This is why it is difficult to make a general statement about how much overall cancer risk increases per year of overweight or obesity.”
The co-author of the study, Hoda Anton-Culver, a professor and chairwoman of epidemiology at the University of California, Irvine said that she and her team have plans for further research. “In addition, other questions that we are thinking about include, ‘Does the age at obesity onset matter? Particularly during childhood, as a young adult or older adult,’ or ‘Does lifelong normal weight actually reduce the risk to develop cancer?’ and ‘Does obesity influence survivorship after cancer diagnosis and treatment?”
She also went on to say that the results from the current study could health care providers to work together with the general public to prevent cancer and control obesity.