Understanding the Link Between Obesity and Common Cancers

Obesity is a complex disease involving excess fat accumulation in the body. While the most common causes are overeating and physical inactivity, obesity can also be influenced by a patient’s metabolism, behavior, environment, and genetics. Beyond visible excess body fat, obesity presents other symptoms, including shortness of breath, excessive sweating, sleep apnea, and intolerance to heat. 

The Centers for Disease Control and Prevention (CDC) use the BMI index chart to determine healthy weight ranges. A person’s BMI is calculated by two factors – height and weight. According to the BMI tool, a normal or healthy weight range is BMI of between 18.5 and 24.9. And a BMI of 30.0 and higher is considered obese. 

It’s important to have this measure since obesity is linked to several health risks, including an increased risk of various cancers. According to data gathered by the CDC, over 650,000 obesity-associated cancers occur in the U.S. each year. The following are types of cancer that have been linked to obesity: 

  • Breast cancer 
  • Colorectal cancer 
  • Esophageal cancer 
  • Gallbladder cancer 
  • Liver cancer 
  • Meningioma 
  • Multiple myeloma 
  • Ovarian cancer 
  • Pancreatic cancer 
  • Renal cancer 
  • Stomach cancer 
  • Thyroid cancer 
  • Uterine cancer 

Obesity also raises the risk for high blood pressure, type 2 diabetes, high LDL cholesterol, coronary heart disease, osteoarthritis, and gallbladder disease. All of which can ultimately increase a patient’s risk of developing cancer. 

The Obesity and Cancer Relationship 

Studies have shown that severely obese women are seven times more likely to develop endometrial cancer than women of normal weight. Obesity in postmenopausal women increases the risk for breast cancer by 20-40%. Obese patients are twice more likely to develop esophageal adenocarcinoma, gastric cardia cancer, liver cancer, and kidney cancer. The risk of meningioma increases by as much as 50% in obese people. Pancreatic cancer risks increase by about 1.5 times in people who are obese. Obesity also increases the risk of colorectal cancer by about 30% and the risk of gallbladder cancer by about 60%. 

Researchers continue to study the reasons why. There are several possible explanations starting with the association between obesity and chronic inflammation, which can result in DNA damage, cell mutation, and environments in which cancers thrive. Obesity can also cause hyperinsulinemia, resulting in abnormally high levels of insulin which fuels cell production and reduces cell death. Adipokines, an active substance found in excess in obese patients, also promotes cancer cell progression,  enhancing cell migration and prompting cancer metastasis. Obesity has also been associated with excessive amounts of estrogen, which increases the risk of breast and ovarian cancers.  

At Tampa Bay Radiation Oncology, more than a thousand men and women diagnosed with cancer each year turn to our trusted team of cancer specialists. We encourage you to call us, ask us a question, or consult with us to get a second opinion so you, too, can experience the difference.