People with obesity have a higher likelihood of developing several types of cancer, including endometrial, postmenopausal breast, colorectal, liver, and pancreatic cancers, and the risk increases with higher levels of body weight for endometrial and postmenopausal breast cancer.

We’ve reviewed the available evidence and found that obesity is linked to a higher likelihood of developing several types of cancer, including endometrial, postmenopausal breast, colorectal, liver, and pancreatic cancers [1]. For endometrial and postmenopausal breast cancer, the risk appears to rise as body weight increases [1]. So far, no studies in our analysis have contradicted this pattern. What we’ve found so far suggests a consistent connection between higher body weight and increased cancer risk for these specific types. The relationship doesn’t appear to be the same across all cancers — it’s strongest for endometrial and postmenopausal breast cancer, where the risk climbs along with weight gain. For the others, the link is still present but the exact shape of that connection isn’t detailed in the evidence we’ve seen. We don’t know why this connection exists from the data provided, and we can’t say whether losing weight reduces the risk. The evidence doesn’t explain mechanisms like hormones, inflammation, or insulin levels — only that higher body weight is associated with higher cancer likelihood in these cases. This doesn’t mean everyone with obesity will develop cancer, nor does it mean that people with lower body weight are free from risk. It simply shows a pattern in the data we’ve reviewed. If you’re concerned about cancer risk, maintaining a healthy weight may be one factor to consider — but it’s not the only one. Other lifestyle choices, genetics, and environmental exposures also play roles, and more research is needed to understand how they all interact.