Excess Weight a Risk Factor for Ovarian Cancer?
Review adds the disease to long list of tumors linked to obesity
By Serena Gordon
TUESDAY, March 11, 2014 (HealthDay News) -- A new report reveals that excess weight raises the risk of yet another kind of cancer, with the latest results linking levels of body fat to ovarian tumors.
The chances for developing many cancers -- such as postmenopausal breast, colorectal, endometrial, esophageal, kidney, gallbladder and pancreatic cancers -- are known to increase with a person's weight, but the evidence for any such link to ovarian cancer has been inconclusive until now, the report authors said.
"We estimated a 6 percent increase in [ovarian cancer] risk per five [points] increase in body-mass index," said report author Dr. Elisa Bandera, an associate professor of epidemiology at the Rutgers Cancer Institute of New Jersey, in New Brunswick. Bandera said the average woman's lifetime risk of ovarian cancer is 1.4 percent.
Body-mass index (BMI) is a rough estimate of a person's body fat based on weight and height. A BMI between 18.5 and 24.9 is considered normal. Between 25 and 29.9 is overweight, and 30 and over is considered obese, according to the U.S. Centers for Disease Control and Prevention.
Almost 600,000 people develop one of the eight cancers linked to overweight and obesity in the United States each year, according to the report compiled by the American Institute for Cancer Research and the World Cancer Research Foundation. If everyone were at a healthy weight, about one in five of those cancers -- or 120,000 cases of cancer a year -- could be prevented, according to the report.
"We know that obesity affects hormones known to affect the cancer process," Bandera said. "It also leads to insulin resistance and [high levels of insulin], as well as a chronic systemic inflammation. Inflammation, in particular, has been a major factor implicated in ovarian cancer development and is also associated with poorer survival."
Registered dietician Samantha Heller said she wasn't surprised by the report's findings.
"Research suggests that up to 90 percent to 95 percent of cancers may be preventable with diet and lifestyle," said Heller, the clinical nutrition coordinator at the Center for Cancer Care at Griffin Hospital, in Derby, Conn. "Of those, as many as 30 percent to 35 percent are linked to diet."
"Contrary to popular belief, fat cells are not the inert compounds we once thought," Heller said. "They are biologically very active cells that produce both anti-inflammatory and inflammatory compounds, as well as hormones and other chemicals."
"An excess of fat cells -- if someone is overweight or obese -- appears to knock off the body's delicate balance of health," Heller said. "This can lead to inflammation and hormonal imbalances, and can promote the growth of cancer cells."
The current report is part of an ongoing project. The last report was published in 2007, Bandera said.