A new report from the U.S. Centers for Disease Control and Prevention (CDC) affirms what experts keep saying: Being overweight puts a person at significantly higher risk for cancer.

A study published Tuesday in Vital Signs, a publication from the CDC and based on data from the 2014 United States Cancer Statistics, finds excess body fat increases the risk for at least 13 different types of cancer. The researchers found that although the overall rate of new cancer diagnoses has decreased since the 1990s, cancers associated with being overweight or obese have dramatically increased.

In 2014, overweight- and obesity-related cancers accounted for up to 40 percent of all cancer diagnoses in the U.S.—roughly 630,000 diagnoses in one year. More than half of all cancer diagnoses in women and roughly a quarter in men fell into this category. Additionally, non-Hispanic blacks and non-Hispanic whites had higher incidence rates of weight-related cancers compared with other racial and ethnic groups. Black males and American Indian/Alaska Native males also had higher incidence rates of these cancers than white males.

Public health officials say the high number of these weight-related cancer diagnoses correlate with the rising rate of obesity in the country. CDC data on body mass index (BMI)—a measure of body fat based on a person’s weight in relation to their height—found roughly two of every three adults could be classified as either overweight or obese. In clinical settings, a BMI of 25 to 29.9 is considered overweight and a BMI of 30 or higher is classified as obese.

Research finds that excess body fat puts a person at risk for some of the cancers with the poorest prognoses. These include meningioma (tumors in the membranes surrounding the brain and spinal cord), multiple myeloma (a cancer of the blood), adenocarcinoma of the esophagus, and cancer of the thyroid. Other cancers strongly associated with being overweight include postmenopausal breast, gallbladder, stomach, liver, pancreas, kidney, ovaries, uterus, colon and rectum.  

Public health officials and physicians say cancer prevention involves maintaining a healthful diet and staying active. But because cancer is generally a disease of aging, it’s important to adhere to recommended screening guidelines, especially in middle age. Organizations such as the American Cancer Society and the U.S. Preventive Services Task Force provide information on when people should make tests such as mammography and colonoscopy a routine part of their medical care.