Weight loss surgery can reduce risk of cancer among women, study says

For the study, researchers compared cancer incidence and mortality stratified by obesity and non-obesity-related cancers, sex, cancer stage and procedure

Weight loss surgeries show a connection to a lower risk of developing cancer (Getty Images/iStockphoto)

Weight loss surgery can help lower the risk of developing cancer, a study has claimed.

The study, conducted by researchers at the University of Utah, also found that cancer mortality rates were significantly lower among female surgical patients compared to those who did not receive any bariatric surgery.

Although population studies have previously established a positive association between body mass index and cancer rates, it has remained unclear whether the reduction in body weight leads to reduced cancer risk.

Researchers say this is due to significant and sustained weight loss in large populations which may be difficult to achieve.

However, because of the substantial and maintained weight loss following bariatric surgery, recent studies have reported reduced cancer rates and lower cancer mortality compared with those who haven’t had the proceedure, according to the study’s authors.

“As scientists study human diseases, an element of discovery is to confirm like results from multiple studies,” said study author Ted Adams. “This research represents another important study that strongly supports the long-term benefits of weight loss surgery in the prevention of cancer.”

Researchers compared cancer prevalence and death rates arranged according to obesity and non-obesity-related cancers, looking at sex, stage of the disease and procedure.

The study looked at 22,000 bariatric surgery patients compared with non-surgical subjects with severe obesity between 1982 to 2019. Each patient was matched up based on age, sex, and body mass index.

Scientists found that the bariatric surgery group had a 25 per cent lower risk of developing any cancers compared to the non-surgery group.

Female patients had a 41 per cent lower risk for developing obesity-related cancers compared to those who did not have surgery done. Cancer risk for male bariatric surgery patients was not lower compared to non-surgery male subjects.

Overall, a significant reduction in cancer risk was shown for cancers such as uterine, ovarian, colon, pre-menopausal breast and post-menopausal breast.

The study also revealed death from cancer was lower by 47 per cent among female bariatric surgery patients in comparison to matched non-surgery female patients.

“Important findings of this study are that bariatric surgery results in lower incidence rates of colon cancer (prior studies have not been consistent),” Dr Adam said.

“Also, both pre and post-menopausal women experience reduced breast cancer incidence following bariatric surgery, which may suggest weight loss among women in either category with severe obesity may benefit from reduced breast cancer.”

The study is available online in the journal Obesity.