“According to the American Cancer Society, obesity is second only to tobacco as a preventable cause of cancer in the United States,” said researcher Dr. Steven Nissen. “This study provides the best possible evidence on the value of intentional weight loss to reduce cancer risk and mortality.”
Long-term health benefits
For the study, the researchers analyzed data from participants enrolled in the Surgical Procedures and Long-term Effectiveness in Neoplastic Disease Incidence and Death (SPLENDID) study. There were over 5,000 adults with obesity who underwent bariatric surgery between 2004 and 2017. The researchers compared those participants' results to outcomes from 25,000 adults with obesity who didn't have the procedure.
The study showed that weight loss as a result of bariatric surgery was associated with a lower risk of cancer and cancer-related death. Under 3% of the participants who had the procedure and lost weight developed cancer, and less than 1% of the group died as a result of cancer. On the other hand, roughly 5% of the participants who didn’t have the surgery developed cancer, and 1.4% of that group died from cancer.
“Patients can lose 20 to 40% of their body weight after surgery, and weight loss can be sustained over decades,” said researcher Dr. Ali Aminian. “The striking findings of this study indicate that the greater the weight loss, the lower the risk of cancer.”
Overall, the study identified a nearly 50% lower risk of dying from cancer for participants who underwent bariatric surgery. The team hopes these findings highlight the importance of consumers following a healthy lifestyle in an effort to potentially lower their risk of cancer.
“Based on the magnitude of benefit shown in our study, weight loss surgery can be considered in addition to other interventions that can help prevent cancer and reduce mortality,” said researcher Dr. Jame Abraham. “Further research needs to be done to understand the underlying mechanisms responsible for reduced cancer risk following bariatric surgery.”