A new study suggests that drugs like Ozempic and Wegovy may help reduce the risk of certain types of cancer.

Individuals who are overweight or obese are more susceptible to 13 types of cancer, and the risk increases the longer a person has been overweight and the greater the excess weight. Approximately 40% of new cancer diagnoses are associated with excess weight, according to the U.S. Centers for Disease Control and Prevention. In 2021, there were about 170 new diagnoses for every 100,000 people, according to CDC data.

However, a study published on Friday in JAMA Network Open found that people with type 2 diabetes treated with a class of GLP-1 drugs were significantly less likely to be diagnosed with 10 out of 13 obesity-related cancers compared to those taking insulin.

The risk of gallbladder cancer, meningioma, pancreatic cancer, and liver cancer was reduced by more than half. There was also a significant decrease in cases of ovarian cancer, colorectal cancer, multiple myeloma, esophageal cancer, endometrial cancer, and kidney cancer.

Excess weight can cause changes in the body such as long-term inflammation, higher than normal insulin levels, insulin-like growth factor, and sex hormones that can lead to cancer, according to the CDC. GLP-1 drugs interact with the systems related to insulin production.

The authors of the study wrote that the new findings linking GLP-1 treatment to a reduced risk of certain cancers “positively compare” to similar effects associated with intensive lifestyle interventions and metabolic obesity surgery found in other trials.

However, the research found that GLP-1 treatment was not associated with a reduced risk of postmenopausal breast cancer, which CDC data shows is the most common type of cancer associated with obesity.

The risk of stomach cancer or thyroid cancer was also not reduced. In fact, other research has found that GLP-1 may interact with insulin production in the body in ways that negatively affect the thyroid, and the study authors note that patients should be aware of potential risks associated with the thyroid included in the drug packaging.

The new study also found that the risk of cancer diagnosis among people with type 2 diabetes did not differ between those treated with GLP-1s compared to those treated with metformin. In fact, the risk of kidney cancer diagnosis was higher among those using GLP-1s compared to those taking metformin.

In this study, researchers from Case Western Reserve University School of Medicine and the MetroHealth System analyzed over a decade of medical records for nearly 1.7 million people with type 2 diabetes.

The authors of the study wrote, “More information is needed on how the reduced cancer risk is related to the amount of weight loss, but the findings provide “preliminary evidence of the potential benefit of GLP-1RAs for cancer prevention in at-risk populations and support further preclinical and clinical studies.”