A large study of black women has added to existing evidence that obesity dramatically increases the risk of developing breast cancer after menopause.
In research presented at the 2014 annual meeting of the American Institute for Cancer Research, scientists found that being overweight or obese increased a postmenopausal black woman’s risk of developing estrogen-receptor positive breast cancer by 31 percent. More than 55 percent of black women are obese. Overweight is defined as having a body mass index (BMI) of 25 to 29.9. A person is considered obese when her BMI exceeds 30. You can calculate yours here.
The study included 15,000 black women. The researchers could not explain why the increased risk was so high among black women. But it may be because breast cancer has, at least, five types. Therefore, women from different ethnic and genetic backgrounds may respond differently to various risk factors.
“We know that breast cancer has several subtypes and there is growing evidence that these subtypes have different risk factors,” said study author Elisa Bandera, M.D., Ph.D., of Rutgers Cancer Institute of New Jersey, in an institute interview. “The distribution of these subtypes and risk factors are different for African Americans and Hispanics compared to white women.”
Weight-related cancer risk is also not exclusive to black women. Obesity increases the risk of several types of cancer — including cancers of the esophagus, uterus, colon and rectum, kidney, pancreas, thyroid and gallbladder — in men and women of all races, but the breast cancer risk appears to be particularly high in black women.
Researchers are not sure how obesity or extra weight contributes to breast cancer, but a large number or scientists think it is because obesity increases the amount of estrogen in the body. It also caused other hormonal imbalances.
Bandera and her team say more research is needed.
Drinking This May Age You
Indulging in sugar-sweetened soda not only contributes to weight gain, but it also may increase your risk of health problems by possibly speeding up the aging process. A new study from the University of California, San Francisco, found accelerated cellular aging in more than 5,000 people surveyed — regardless of age, income or race — who consumed an average of 12 ounces of sugar-sweetened soda a day. They concluded that drinking a 20-ounce soda a day was associated with 4.6 years of additional biological aging.